Naked Science Forum
On the Lighter Side => New Theories => Topic started by: Farsight on 10/01/2010 15:52:18
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I've been doing a fair amount of research of original material, and the picture of general relativity that I get seems to be very different to what I was taught. For example, people tend to say the speed of light is constant, and Einstein said it. But it isn't true. Yes, he started with this as a postulate in 1905, but in 1911 he wrote On the Influence of Gravitation on the Propagation of Light (http://www.relativitybook.com/resources/Einstein_gravity.html), where we can see his ideas evolving as he talks about c = c0 (1 + Φ/c²). Then in 1916 in section 22 of Relativity: The Special and General Theory (http://www.gutenberg.org/etext/5001) he talks further:
"In the second place our result shows that, according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity and to which we have already frequently referred, cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position. Now we might think that as a consequence of this, the special theory of relativity and with it the whole theory of relativity would be laid in the dust. But in reality this is not the case. We can only conclude that the special theory of relativity cannot claim an unlimited domain of validity; its results hold only so long as we are able to disregard the influences of gravitational fields on the phenomena (e.g. of light)".
IMHO people tend to see the word velocity in the 1920 translation without seeing the context. Many skip over his reference to "one of the two fundamental assumptions", and don't see that he's talking about a serious issue with the SR postulate of the constant speed of light. Many do not realise that Einstein didn't speak English in 1916, and what he actually said was die Ausbreitungsgeschwindigkeit des Lichtes mit dem Orte variiert. This translates into the speed of light varies with the locality (http://translate.google.com/translate_t?prev=hp&hl=en&js=y&text=die+Ausbreitungsgeschwindigkeit+des+Lichtes+mit+dem+Orte+variiert+&file=&sl=de&tl=en&history_state0=#). He was saying the speed varies with position, hence the reference to that postulate. And what he also said, is that this causes the light to follow a curvilinear path like a car veers when the near-side wheels encounter mud at the side of the road.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fcsep10.phys.utk.edu%2Fastr161%2Flect%2Fhistory%2Feinstein_clerk.gif&hash=0665ac13890119e010246d39138389f1)
People often react badly this. Einstein talking about the variable speed of light does not fit with the relativity they've been taught. They don't appreciate that relativity today is somehow different to Einstein's relativity. People think Einstein told us about curved spacetime, but when you read The Foundation of the General Theory of Relativity (http://www.alberteinstein.info/gallery/pdf/CP6Doc30_English_pp146-200.pdf), incredibly, it's just not there. Yes, he talks about geometry and curvature and space-time, but he's giving the equations of motion, through space. He doesn't talk about "motion through spacetime" like people do these days. Surely everybody knows you can't move through spacetime, it's just the mathematical space where we plot our lines. There's other things that people aren't taught. Such as how Einstein was still derided by many theoreticians even in 1923. You can see a reference to this on page 53 of Graham Farmelo's Dirac biography The Strangest Man:
"At that time, Cunningham and Eddington were streets ahead of the majority of their Cambridge colleagues, who dismissed Einstein's work, ignored it, or denied its significance".
Many people don't know that despite the media accolades and public adulation, Einstein drifted out of the mainstream from 1927 when he fell out with Bohr and others over quantum mechanics. They don't know that General Relativity was a "cottage industry" until the sixties, when the Golden Age (http://en.wikipedia.org/wiki/Golden_age_of_general_relativity) changed it significantly:
"The Golden Age of General Relativity is the period roughly from 1960 to 1975 during which the study of general relativity, which had previously been regarded as something of a curiosity, entered the mainstream of theoretical physics. During this period, many of the concepts and terms which continue to inspire the imagination of gravitation researchers (and members of the general public) were introduced, including black holes and 'gravitational singularity'. At the same time, in closely related development, the study of physical cosmology entered the mainstream and the Big Bang became well established... A number of simultaneous paradigm shifts characterize the Golden Age of general relativity. First and foremost, the Big Bang became the canonical cosmological model. Other paradigm shifts included a growing appreciation of the: Role of curvature in general relativity..."
Nor do most people know that in 1949 Einstein and Godel worked out that time is cofounded with motion through space, not with space. It's there in A World without Time: The Forgotten Legacy of Godel and Einstein (http://www.amazon.co.uk/World-Without-Time-Forgotten-Einstein/dp/0713993871) by Palle Yourgrau. But perhaps the signal most important thing most people don't know, is that whilst aether is a taboo word which is most definitely out of the mainstream, Einstein's gave his Leyden address in 1920. And the title is Ether and the theory of relativity (http://www.zionism-israel.com/Albert_Einstein/Albert_Einstein_Ether_Relativity.htm). There's Einstein, talking about space and calling it an aether:
"Mach’s idea finds its full development in the ether of the general theory of relativity. According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that ‘empty space’ in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty".
All in all it adds up to some huge differences, and some surprises. It seems that relativity has always been the Cinderella of modern physics, and despite his vast reputation, Einstein was hardly in the mainstream at all. Moreoever his understanding of gravity doesn't seem to be mainstream any more. What's especially surprising is how similar it is to the way Newton described it in Opticks:
Doth not this aethereal medium in passing out of water, glass, crystal, and other compact and dense bodies in empty spaces, grow denser and denser by degrees, and by that means refract the rays of light not in a point, but by bending them gradually in curve lines? ...Is not this medium much rarer within the dense bodies of the Sun, stars, planets and comets, than in the empty celestial space between them? And in passing from them to great distances, doth it not grow denser and denser perpetually, and thereby cause the gravity of those great bodies towards one another, and of their parts towards the bodies; every body endeavouring to go from the denser parts of the medium towards the rarer?" queries 20 & 21
The language is different, but the underlying concept is the same. The energy tied up as the matter of a planet "conditions" the surrounding space to create a non-constant gμν along with a gradient in c which causes curvilinear motion. To many people this is unacceptable, because it isn't what they've been taught. It doesn't matter that it comes from Einstein and Newton and is supported by experimental evidence, they refuse to believe it.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F3%2F39%2FGodfreyKneller-IsaacNewton-1689.jpg%2F225px-GodfreyKneller-IsaacNewton-1689.jpg&hash=a40ade58ea2d736396ed12e47876e204)
Show them two astronauts carrying parallel-mirror light clocks at different locations, and they will refuse to admit what the different readings on those light clock is telling them. They'll talk about coordinate speed and time dilation and spacetime curvature, anything to avoid what's in plain view: in a place where the gravitational potential is lower, the light goes slower.
Why is it that people seem unable to see what Einstein actually said, or the evidence that supports it?
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I've been doing a fair amount of research of original material, and the picture of general relativity that I get seems to be very different to what I was taught.
Have you actually studied relativistic physics at the university level? Have you studied relativistic physics at the post-graduate level? Where and how were you "taught"?
For example, people tend to say the speed of light is constant, and Einstein said it. But it isn't true. Yes, he started with this as a postulate in 1905, but in 1911 he wrote On the Influence of Gravitation on the Propagation of Light (http://www.relativitybook.com/resources/Einstein_gravity.html), where we can see his ideas evolving as he talks about c = c0 (1 + Φ/c²). Then in 1916 in section 22 of Relativity: The Special and General Theory (http://www.gutenberg.org/etext/5001) he talks further:
"In the second place our result shows that, according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity and to which we have already frequently referred, cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position. Now we might think that as a consequence of this, the special theory of relativity and with it the whole theory of relativity would be laid in the dust. But in reality this is not the case. We can only conclude that the special theory of relativity cannot claim an unlimited domain of validity; its results hold only so long as we are able to disregard the influences of gravitational fields on the phenomena (e.g. of light)".
IMHO people tend to see the word velocity in the 1920 translation without seeing the context. Many skip over his reference to "one of the two fundamental assumptions", and don't see that he's talking about a serious issue with the SR postulate of the constant speed of light. Many do not realise that Einstein didn't speak English in 1916, and what he actually said was die Ausbreitungsgeschwindigkeit des Lichtes mit dem Orte variiert. This translates into the speed of light varies with the locality (http://translate.google.com/translate_t?prev=hp&hl=en&js=y&text=die+Ausbreitungsgeschwindigkeit+des+Lichtes+mit+dem+Orte+variiert+&file=&sl=de&tl=en&history_state0=#). He was saying the speed varies with position, hence the reference to that postulate. And what he also said, is that this causes the light to follow a curvilinear path like a car veers when the near-side wheels encounter mud at the side of the road.
I had thought that after being banned from yet another message board, you had finally given up on this misunderstanding of yours. You have previously claimed that you cannot do the detailed mathematics of general relativity and this is holding you back from actually following what this passage from Einstein actually means. Anyone who keeps reading beyond the passage you have cherry-picked here soon learns, if they can follow the mathematics in which the physics is written, that Einstein does not mean anything like what he said in 1911. He certainly does not mean anything like your mud and wheels example.
People often react badly this.
People react badly to your continued cherry-picking of two passages from Einstein, your choice to ignore any of the actual physics of Einstein, and your refusal to answer questions. This is what provokes a reaction to what you write.
People think Einstein told us about curved spacetime, but when you read The Foundation of the General Theory of Relativity (http://www.alberteinstein.info/gallery/pdf/CP6Doc30_English_pp146-200.pdf), incredibly, it's just not there. Yes, he talks about geometry and curvature and space-time, but he's giving the equations of motion, through space.
No, he is not. You have admitted that you cannot do the mathematics of differential geometry. I suggest you take the time to learn this mathematics so that you can understand just how wrong you are here.
He doesn't talk about "motion through spacetime" like people do these days.
People do not do this. Please provide a specific reference from a credible source if you think otherwise.
But perhaps the signal most important thing most people don't know, is that whilst aether is a taboo word which is most definitely out of the mainstream, Einstein's gave his Leyden address in 1920. And the title is Ether and the theory of relativity (http://www.zionism-israel.com/Albert_Einstein/Albert_Einstein_Ether_Relativity.htm). There's Einstein, talking about space and calling it an aether:
"Mach’s idea finds its full development in the ether of the general theory of relativity. According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that ‘empty space’ in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty".
As the author of the page that you link to to provide this quotation writes, "This address has been frequently misunderstood as positing that a return of the ether theory." That you entirely miss the point of the lecture is not something you should be proud of. Again, you should learn the actual mathematics so that you can understand what gμν really means.
What's especially surprising is how similar it is to the way Newton described it in Opticks:
Doth not this aethereal medium in passing out of water, glass, crystal, and other compact and dense bodies in empty spaces, grow denser and denser by degrees, and by that means refract the rays of light not in a point, but by bending them gradually in curve lines? ...Is not this medium much rarer within the dense bodies of the Sun, stars, planets and comets, than in the empty celestial space between them? And in passing from them to great distances, doth it not grow denser and denser perpetually, and thereby cause the gravity of those great bodies towards one another, and of their parts towards the bodies; every body endeavouring to go from the denser parts of the medium towards the rarer?" queries 20 & 21
The language is different, but the underlying concept is the same. The energy tied up as the matter of a planet "conditions" the surrounding space to create a non-constant gμν along with a gradient in c which causes curvilinear motion. To many people this is unacceptable, because it isn't what they've been taught. It doesn't matter that it comes from Einstein and Newton and is supported by experimental evidence, they refuse to believe it.
One can always cherry-pick quotations from history that seem to look like modern physics. However, there is no relationship between the physics of the Opticks and the physics of GR. Additionally, the quotation that you have chosen comes from Newton's remarks on alchemy. If you unquestioningly support what Newton writes here, you seem to unquestioningly support all of Newton's alchemy.
Additionally, you can show no experimental evidence that demonstrates that there is a medium at work in generating the results of GR. If you can, please demonstrate with actual numbers and calculations. Since you admittedly cannot do the mathematics of GR, I cannot understand how you can believe your claims here.
Show them two astronauts carrying parallel-mirror light clocks at different locations, and they will refuse to admit what the different readings on those light clock is telling them.
Since this experiment has never been done, you cannot claim that this is experimental evidence.
Why is it that people seem unable to see what Einstein actually said, or the evidence that supports it?
Because they do not want to spend the time to learn the mathematics and physics involved. Thus they ignore the details of what Einstein produced and instead cherry pick out quotations that support their preconceptions.
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Physbang, you aren't countering the reportage I've given here. Instead you're attempting to deny it by dismissing what Einstein and Newton actually said as "cherry picking" and "alchemy". You're trying to support your own preconceptions, and without scientific evidence and carefully-contructed logical argument, your response is inadequate. Claiming that my mathematics or education is lacking or that I've been repeatedly banned doesn't make up for sincere discussion of this important matter. It's quite clear what Einstein said, and my astronauts example is fully supported by the GPS clock adjustment and the Shapiro time delay. The evidence is there, so please be aware that I started this thread as a spin-off to something that cropped up on a thread concerning gravity and work: http://www.thenakedscientists.com/forum/index.php?topic=27444.msg294032#msg294032.
All: see http://arxiv.org/abs/physics/0204044 for Einstein's Gravitational Field by Peter M Brown. It's a very interesting paper, well worth reading:
Abstract: There exists some confusion, as evidenced in the literature, regarding the nature of the gravitational field in Einstein's General Theory of Relativity. It is argued here the this confusion is a result of a change in interpretation of the gravitational field. Einstein identified the existence of gravity with the inertial motion of accelerating bodies (i.e. bodies in free-fall) whereas contemporary physicists identify the existence of gravity with space-time curvature (i.e. tidal forces). The interpretation of gravity as a curvature in space-time is an interpretation Einstein did not agree with.
Peter M Brown posts here as Pmb, and knows his stuff. He and I don't always agree on the finer points, but we converse in a pleasant manner, and let's face it, if everybody agreed on everything, there wouldn't be much to talk about!
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Claiming that my mathematics or education is lacking or that I've been repeatedly banned doesn't make up for sincere discussion of this important matter.
These claims are evidence that you are not interested in discussion and that you are perhaps incapable of such discussion. You continually misrepresent Einstein and when called on this, you become belligerent. It will happen here.
People have asked you before to do a direct demonstration that will show that you are correct: if you could perhaps run through the advance of the perihelion of Mercury or through the calculation of the rotation of any galaxy currently being used to detect dark matter, then you could easily show that your position is correct. You cannot do these direct demonstrations, unfortunately for your position.
It's quite clear what Einstein said, and my astronauts example is fully supported by the GPS clock adjustment and the Shapiro time delay.
Please show us the calculations involved in the GPS clock adjustment and Shapiro time delay and show us where they come up in your astronaut example. Please use specific values and calculations in your example.
All: see http://arxiv.org/abs/physics/0204044 for Einstein's Gravitational Field by Peter M Brown. It's a very interesting paper, well worth reading:
But there is probably something very wrong with this paper and the position of the author because the author has no published work in the field, despite the age of the paper. Can you find any evidence that is accepted by any group of peers in physics or in the philosophy of science?
Like always, you will fail to directly answer these questions because to take these questions seriously would reveal the horrible flaws in your position and the evidence for it.
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PhysBang, since you refuse to read your email or answer it, I must do this in public.
Personal attacks will not be allowed - period. PhysBang may not post for two weeks and another breach will result in a permanent ban. You did not heed the email sent and have refused to curb you ad-hominem post. You then may not have the privalage of posting to this site. If at the end of the two weeks you continue to make ad-hominem responses, the ban will be permanent.
JimBob, Moderator
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For the record, I'm very interested in discussion, and whilst the odd cross word sometimes escapes my lips, I'm not belligerent. I decline to give a mathematical demonstration of say the perihelion advance of Mercury because it's a diversion from the matter at hand. For GPS the relevant information is that the satellites employ atomic clocks, which count microwave pulses. Microwaves are electromagnetic radiation, essentially light. A quick check on GPS and general relativity (http://en.wikipedia.org/wiki/Global_Positioning_System#Special_and_general_relativity) then tells us "general relativity predicts that the atomic clocks at GPS orbital altitudes will tick more rapidly, by about 45.9 μs per day, because they have a higher gravitational potential than atomic clocks on Earth's surface". This will be reliable, and is clear scientific evidence that is fully in accord with Einstein's words and pmb's paper. Dismissing such evidence by claiming it isn't peer-reviewed sounds unreasonable, and besides, a quick search on arxiv on variable-speed of light (http://arxiv.org/find/grp_physics/1/ti:+AND+light+AND+of+AND+variable+speed/0/1/0/all/0/1) yields a wealth of papers. I note one by Alexander Unzicker entitled The VSL Discussion: What Does Variable Speed of Light Mean and Should we be Allowed to Think About It? (http://arxiv.org/abs/0708.2927)
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I would ask one question of Phys, can he show us one cubic nanometer of space that does not contain radiation in the Universe? If the answer is no then it could be said that radiation is the aether of space.
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PhysBang has lost the privilege of answering for two weeks. If he choose, he can answer in a couple of weeks.
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Space is somewhat unique Ron. It's seemingly not there but it supports waves and fields, and it has this vacuum energy, so it isn't nothing. And because it has this energy, it has a mass equivalence of sorts. But the idea of motion cannot be applied to it, so it doesn't have mass like a cannonball. It isn't "matter" like the old luminiferous aether. I think of LIGO trying to detect gravity waves see http://www.ligo-la.caltech.edu/LLO/overviewsci.htm where you can read:
"If the two arms have identical lengths, then interference between the light beams returning to the beam splitter will direct all of the light back toward the laser. But if there is any difference between the lengths of the two arms, some light will travel to where it can be recorded by a photodetector".
Then I look at that Leyden address again and my attention is drawn to Weyl:
"Of course it would be a great advance if we could succeed in comprehending the gravitational field and the electromagnetic field together as one unified conformation. Then for the first time the epoch of theoretical physics founded by Faraday and Maxwell would reach a satisfactory conclusion. The contrast between ether and matter would fade away, and, through the general theory of relativity, the whole of physics would become a complete system of thought, like geometry, kinematics, and the theory of gravitation. An exceedingly ingenious attempt in this direction has been made by the mathematician H. Weyl; but I do not believe that his theory will hold its ground in relation to reality".
..and I say to myself I should do more research here. See for example http://www.weylmann.com/conformal.pdf.
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farsight, vacuum energy is a concept brought on by the invention of another hypothetical particle, the virtual particle, required to maintain the illusion that QM can explain the propagation of light.
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I'm afraid it isn't Ron. Einstein talked about the stress-energy of space long before virtual particles were proposed. And the Casimir effect demonstrates that there's a real phenomena there. It doesn't demonstrate that virtual particles are real particles, but it does demonstrate that vacuum energy is something real. For myself, I think there's a lot of merit in Evanescent modes are virtual photons, A. A. Stahlhofen et al 2006 Europhys. Lett. 76 189-195. See http://www.iop.org/EJ/abstract/0295-5075/76/2/189
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If all of space contains radiation, how would we know that fact does not somehow explain the observations. Until someone shows proof of virtual particles I will find it difficult to except them. You and I both think matter is a wave. We can point to the fact matter anti-matter annihilation's produce nothing but radiation but that test convinces no one that we're right. There is no spray of quarks or any other particles just radiation.
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I'm not asking you to accept virtual particles as real particles, Ron. Just that there's something real underlying say the attraction of an electron and a proton in a hydrogen atom. Quantum Electrodynamics is a good theory that employs virtual particles to come up with accurate preductions, but Feynman never said that these virtual particles are real particles. I think the best way to think of them, is like the "virtual pennies" that are added to your bank account when your employer pays in your salary. There are no actual pennies flying around. They're just accounting units for doing calculations.
Plenty of people, and I mean professional physicists, are coming to appreciate that particles like electrons and protons are wave configurations. Whilst it has rock-solid provenance going back to de Broglie and Schrödinger, it just hasn't been in the popular press yet. Give it time, and I'm sure it will be. It's amazing how long things can take to work their way through from journals into magazines and TV programs and text books, particularly when competing theories are involved.
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I do understand their use is a tool(something like a crutch)used as a mental aid in make some predictions about how energy is moved back and forth in the Universe. In my editorial thread I speak of molecular collisions and the squashing the respective fields. If the individual particles that make up the molecules are some sort of wave that can maintain itself for 10^30 years how does it affect the space around it to create it's infinite field? Did Einstein ever explain that field? It appears that questions along with answers only produce more questions.
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I'd say no, Einstein didn't explain it, but after everything I've learned I wouldn't be surprised if somebody pointed out some obscure paper he'd written and said here it is. Maybe http://en.wikipedia.org/wiki/Einstein%E2%80%93Cartan_theory goes some way towards it, wherein electron spin affects the surrounding space via something akin to frame-dragging.
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I suspect frame dragging is also a function of time dilation.
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It isn't time dilation, Ron. It's more like a "twist":
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Feinstein.stanford.edu%2FLibrary%2Fimages%2Fspacetime-frame-dragging.jpg&hash=c86b3e2318d66946259c32ed4988685e)
If you moved through a region of twisted space, it would make you turn. Check out Gravitomagnetism (http://en.wikipedia.org/wiki/Gravitomagnetism) and Gravity Probe B. Also see near the back of Minkowski's Space and Time where he emplys a wrench analogy:
"Then in the description of the field produced by the electron we see that the separation of the field into electric and magnetic force is a relative one with regard to the underlying time axis; the most perspicious way of describing the two forces together is on a certain analogy with the wrench in mechanics, though the analogy is not complete".
He's talking about a screw machanism. Check out On Physical Lines of Force and there's Maxwell talking about a screw mechanism too: http://en.wikipedia.org/w/index.php?title=File:On_Physical_Lines_of_Force.pdf&page=53. This is why we have the right hand rule. Imagine a stack of electrons in a wire. Their electric field is a "twist" field, so when a test particle moves down past them, or they move up past it, there's a rotation. It "turns". The thing to remember is that it's an electromagnetic field. It isn't an electric field that's separate from a magnetic field. There's only one field there, the electromagnetic field, and if you could see it, it would look something like a drill bit. A drill bit is twisted. Make a fist round a drill bit with your right hand, and push from the bottom. It turns. It's breathtakingly simple once it clicks.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F5%2F56%2FRight_hand_rule.png%2F180px-Right_hand_rule.png&hash=d39b2fdc74477556b92bfbbb417f260d)
Hi Good Elf!
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Hi Farsight,
I agree entirely with your POV. I will add my two cents worth just to reiterate and reinforce some of the points you made. You have chosen a very interesting aspect of all physics. I notice that there is some controversy regarding Einstein's paradigm of "warped spacetime" in General Relativity. I realize the topic is moving on from there but I have only recently joined and this is my first post here so forgive me for touching base. Einstein treated gravity in a different way to electromagnetism. It "seemed very plausible" since electromagnetism relies on what appears to be underlying permanent charges which come in two varieties... nominally positive and negative while "mass", which plays the role of a "charge" in gravity, comes in only one form of "positive mass" and no "anti-mass" or anti-gravational mass... a purely hypothetical opposite pole to mass... something that would repel mess rather than attract it. I am not referring to anti-particles here but to something quite separate.
In the case of electromagnetic influence... it's influence is usually blocked by a couple of mils of opaque insulating material. This is because "force" superficially appears to have two ways to transmit itself. There is a local expression of forces (evanescent field) and a distant expression of forces (far field). The local expression of forces are in the near field and are associated with the notion of "virtual particles" in which the fluxes of "field lines" associated with the sources are not "detached from their sources" and the distant expression of forces and are associated with a propagating "force carrier or bosons"... in which the fields are dissociated from their sources and this leads to the bosons of the photon for electromagnetism and the graviton for "gravity". The propagated influence of photons are absorbed and converted to other forms of energy in "sinks". Gravitational influence is not so easily "dissipated" simply because there are no "sinks" for gravity only "sources"..
It is an interesting point to ponder that aside from the fact that light travels at the speed of light and is simultaneously affected by electrodynamics and also by gravity and "falls" identically like a projectile along the "surface of spacetime" and is a "limiting case of material projectiles" as V -> C. This suggests there really is not action at a distance dependent on the mutual mass between particles since such a theory would mean that if one of the two "attractive" objects was of zero rest mass there would be no "attraction" at all. It is possible to demonstrate very effectively that photons have zero rest mass. So... photons "fall" like a very light stone that is traveling infinitely close to the speed of light.
Gravity is deemed "symmetric" (unipolar) while electromagnetism is "anti-symmetric" (bipolar). We often discuss "forces" when we deal with these two different phenomena but the theory of forces cannot account for this alone since "forces" are actions at a distance while everything appears to point to an explanation due to the interaction between "particles" which depends on their mutual interactions. I would point out "a particle" is also a paradigm that might be hindering our ideas about "forces".
That "primary force" of gravity and the "primary force" of electromagnetism (charge and magnetism) do not appear to be primarily the result of the exchange of "force carriers" or due to continuous accelerations in the matter or charge sources. Einstein thought of gravity as a pseudo-force and is explained by his local theory of spacetime curvature.. his "General Theory of Gravatation" (ED: spacetime was a concept Minkowski invented not truly Einstein's own original idea but "near enough"). This was summed up by John A. Wheeler as "Matter tells space how to curve, and space tells matter how to move". Action at a distance for these "gross effects" is not required. A simplistic view of this concept is like a skateboard in a skateboard park.. the board moves according to it's velocity and the curvature directly under it's wheels at each instant in time and does not require the concept of a "distant source of force" attracting the skateboard be needed to explain it. That was another visual analogy so do not think too much about that simple notion.
Likewise gravity "appears" to not require distant forces to motivate the gross motion of planets of the rotation of galaxies... it gets it "moving orders" from the local curvature of spacetime. The complementary particle to the photon... the graviton would then play the same role as a photon in electromagnetism and would involve "real" gravitons but gravity... that we measure mass by using a set of scales... plays the same role as the electromagnetic forces we see in magnets electric motors and moving charges of various types... the mass "fluxes" (like the electromagnetic fluxes) remaining attached to the "sources" (whatever they are)and neither "primary force" requires propagating light or propagating gravitons. what I mean by this in the case of gravity curved spacetime explains the motion of celestial bodies while in electromagnetism charged particles (and magnetism) and their quasi-stationary fields explain the "forces" between charges. Each of these phenomena might appear to be separate and acting on different "manifolds" but a theory of combing these manifolds was Einstein's dream and is the base motivation for current String Theory today. The distant influence of both gravity and light due to carriers of force require the idea of accelerations in the sources generating these particles. There are some problems with all these theories.
I am not "undervaluing" the influence of light since almost everything in the universe we can sense is the effect of either quantum electrodynamics or of gravitation. The other forces (weak, strong forces) are not essential for the things we appreciate (may also be even detrimental) on a day to day basis and are involved with "nuclear radiations" of various kinds... so "light" and therefore photons in all their forms are very important to the way our world works... both real photons and virtual photons in all the forms of the motion of sources of the apparent permanent charge. Of course matter also plays a role in there as "mass" and as "matter waves" but this is not explained by QED.
Now returning to the core issue... Regarding the curvature of spacetime in the General Theory of Gravatation it might be "directly compared" with the property of optical diffraction in refractive materials. So instead of speaking about curved spacetime and Einstein had spoken in terms of a "gravitational refractive index" then this would effectively embed "matter" in an unseen medium whose property was to alter the speed of light rather than "warp some kind of unseen membrane" which we currently identify as "mass". The optical refractive index of a medium is a reflection of the speed of light through the medium and the speed of light in a vacuum.
Refraction is the change in direction of a wave due to a change in its speed. This is most commonly observed when a wave passes from one medium to another at an angle. Refraction of light is the most commonly observed phenomenon, but any type of wave can refract when it interacts with a medium, for example when sound waves pass from one medium into another or when water waves move into water of a different depth...
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fupload.wikimedia.org%2Fmath%2F2%2F0%2Fa%2F20aa1e3d192ecb3164ac4f2095c86cd3.png&hash=92c336f82fd3ec5c0cb53dcade0315c0)
Wikipedia: Refraction (http://en.wikipedia.org/wiki/Refraction)
With gravity we cannot see any medium so we usually do not invoke a material medium to "conduct" gravity. None has ever been detected. Still... as a pure paradigm it "might be useful" to consider this property as if it did exist. This phenomenon exhibits "optically" as Einstein's Rings (http://en.wikipedia.org/wiki/Einstein_ring) and we might like to consider spacetime curvature having a variable gravito-optical density reflecting and paralleling the idea of warping of a membrane. But are refractive index and a hypothetical gravito-optical density the same... No... But why not? That is a very interesting question.
We actually cannot verify the existence of either a "physical spacetime" or a vacuum refractive index altering material properties existing in the empty space around matter... That might be interpreted as a vacuum energy density in some way. This really is not a required part of the Einstein's Theory since all theories have their paradigms and they are taken up or discarded when required. What is important is we all realize that, while the paradigm assists us in visualizing the phenomena, it should not be thought of as the only way of understanding it and the future of science will change it's paradigms more often than some may want. The mathematical description of the theory should be attempting to describe this "mental picture" we have developed of these "forces" but do not be surprised when an experiment changes the results of some of the theory the paradigm is radically modified to account for these perceived conceptual anomalies.
As an additional point... There is very little differentiating "virtual" photons from "real" photons since photons can be created on demand and a sufficiently energetic process can produce these "real" photons from a source embedded in "virtual" photons... A radio transmitter is a source such as this... even the transitions in an atom can produce photons from virtual photons. On the other hand it is still to be shown experimentally that gravitons really exist to enable the analogy between the photon and electromagnetism and the graviton and gravity to be extended into an overall paradigm.
Cheers
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Far, my understanding is that frame dragging occurs only if an object or particle is spinning. If the Earth had no rotation, an object placed anywhere on a sphere two hundred thousand kilometers from the Earth would experience the some magnitude and direction of acceleration as an object placed anywhere on that sphere.
Elf, Einstein spent the last thirty years of his life trying to unite electromagnetism and gravity. Some materials will block certain frequencies of the EM spectrum but no material, we know of, will block infrared. The best thermos bottle ever made, even with a complete vacuum, will have some infrared EM. There is no place in the Universe, man made or natural, where there is no radiation.
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There is a local expression of forces (evanescent field) and a distant expression of forces (far field). The local expression of forces are in the near field and are associated with the notion of "virtual particles" in which the fluxes of "field lines" associated with the sources are not "detached from their sources"
I couldn't agree more, Good Elf. Andrew Meulenberg told me about this maybe a year back, and others think this too, see http://www.iop.org/EJ/abstract/0295-5075/76/2/189. Apologies if I've mentioned it before, I'll send you a copy in case I haven't, and double apologies in case it was you who told me about it.
It is an interesting point to ponder that aside from the fact that light travels at the speed of light and is simultaneously affected by electrodynamics and also by gravity and "falls" identically like a projectile along the "surface of spacetime" and is a "limiting case of material projectiles" as V -> C. This suggests there really is not action at a distance dependent on the mutual mass between particles since such a theory would mean that if one of the two "attractive" objects was of zero rest mass there would be no "attraction" at all. It is possible to demonstrate very effectively that photons have zero rest mass. So... photons "fall" like a very light stone that is traveling infinitely close to the speed of light.
Not quite, Good Elf! Maybe you were keeping it simple, but see that squared-off circle representing a single electron? It's deflected half as much as light:
..←
↓....↑
..→
Gravity is deemed "symmetric" (unipolar) while electromagnetism is "anti-symmetric" (bipolar). We often discuss "forces" when we deal with these two different phenomena but the theory of forces cannot account for this alone since "forces" are actions at a distance while everything appears to point to an explanation due to the interaction between "particles" which depends on their mutual interactions. I would point out "a particle" is also a paradigm that might be hindering our ideas about "forces".
Excellent. People don't seem to understand what Newton was getting at when he said "so great an absurdity".
That "primary force" of gravity and the "primary force" of electromagnetism (charge and magnetism) do not appear to be primarily the result of the exchange of "force carriers" or due to continuous accelerations in the matter or charge sources. Einstein thought of gravity as a pseudo-force and is explained by his local theory of spacetime curvature.. his "General Theory of Gravatation" (ED: spacetime was a concept Minkowski invented not truly Einstein's own original idea but "near enough").
It is so refreshing to hear somebody who actually knows the history, Good Elf.
This was summed up by John A. Wheeler as "Matter tells space how to curve, and space tells matter how to move".
More's the pity that you and I know that a better way of saying it is "energy tells spacetime how to curve". Energy causes gravity, matter only causes gravity because of the energy content. If the space was curved, then regardless of velocity all balls thrown across a room would describe the same arc.
Action at a distance for these "gross effects" is not required. A simplistic view of this concept is like a skateboard in a skateboard park.. the board moves according to it's velocity and the curvature directly under it's wheels at each instant in time and does not require the concept of a "distant source of force" attracting the skateboard be needed to explain it. That was another visual analogy so do not think too much about that simple notion.
I like it, Good Elf. Here's a similar one I've used:
Imagine a swimming pool. Every morning you swim from one end to the other in a straight line. In the dead of night I truck in a load of gelatine powder and tip it all down the left hand side. This starts diffusing across the breadth of the pool, imparting a viscosity gradient from left to right. The next morning when you go for your swim, something's not right, and you find that you're veering to the left. If you could see your wake, you'd notice it was curved. That's your curved spacetime, because the pool is the space round a planet, the viscosity gradient is Einstein's non-constant gμν, and you're a photon. As to how the gradient attracts matter, consider a single electron. We can make an electron along with a positron from light, via pair production. Since the electron also has spin, think of it as light trapped in a circular path. So if you're swimming round and round in circles, whenever you're swimming up or down the pool you're veering left. Hence you find yourself working over to the left. That's why things fall down.
Likewise gravity "appears" to not require distant forces to motivate the gross motion of planets of the rotation of galaxies... it gets it "moving orders" from the local curvature of spacetime. The complementary particle to the photon... the graviton would then play the same role as a photon in electromagnetism and would involve "real" gravitons but gravity... that we measure mass by using a set of scales... plays the same role as the electromagnetic forces we see in magnets electric motors and moving charges of various types... the mass "fluxes" (like the electromagnetic fluxes) remaining attached to the "sources" (whatever they are)and neither "primary force" requires propagating light or propagating gravitons. what I mean by this in the case of gravity curved spacetime explains the motion of celestial bodies while in electromagnetism charged particles (and magnetism) and their quasi-stationary fields explain the "forces" between charges. Each of these phenomena might appear to be separate and acting on different "manifolds" but a theory of combing these manifolds was Einstein's dream and is the base motivation for current String Theory today. The distant influence of both gravity and light due to carriers of force require the idea of accelerations in the sources generating these particles. There are some problems with all these theories.
Yes, it's very sad. The virtual particles of QED morphed into real particles somewhere along the line. But Einstein's dream is not shattered, just overshadowed. You know that the electromagnetic field is curved space, don't you.
I am not "undervaluing" the influence of light since almost everything in the universe we can sense is the effect of either quantum electrodynamics or of gravitation. The other forces (weak, strong forces) are not essential for the things we appreciate (may also be even detrimental) on a day to day basis and are involved with "nuclear radiations" of various kinds... so "light" and therefore photons in all their forms are very important to the way our world works... both real photons and virtual photons in all the forms of the motion of sources of the apparent permanent charge. Of course matter also plays a role in there as "mass" and as "matter waves" but this is not explained by QED.
I share your sentiment here. QED was always lacking an intuitive explanation of how it worked and what was the reality underlying the virtual particles. One has to understand the photon and the electron before one can make robust progress at the QCD level.
Now returning to the core issue... Regarding the curvature of spacetime in the General Theory of Gravatation it might be "directly compared" with the property of optical diffraction in refractive materials. So instead of speaking about curved spacetime and Einstein had spoken in terms of a "gravitational refractive index" then this would effectively embed "matter" in an unseen medium whose property was to alter the speed of light rather than "warp some kind of unseen membrane" which we currently identify as "mass". The optical refractive index of a medium is a reflection of the speed of light through the medium and the speed of light in a vacuum.
Music to my ears. The non-constant guv that causes curvilinear motion.
With gravity we cannot see any medium so we usually do not invoke a material medium to "conduct" gravity. None has ever been detected. Still... as a pure paradigm it "might be useful" to consider this property as if it did exist. This phenomenon exhibits "optically" as Einstein's Rings (http://en.wikipedia.org/wiki/Einstein_ring) and we might like to consider spacetime curvature having a variable gravito-optical density reflecting and paralleling the idea of warping of a membrane. But are refractive index and a hypothetical gravito-optical density the same... No... But why not? That is a very interesting question.
It is that, Good Elf. Space is just so utterly unique. The best phrase I can come up with is energy density.
We actually cannot verify the existence of either a "physical spacetime" or a vacuum refractive index altering material properties existing in the empty space around matter... That might be interpreted as a vacuum energy density in some way. This really is not a required part of the Einstein's Theory since all theories have their paradigms and they are taken up or discarded when required. What is important is we all realize that, while the paradigm assists us in visualizing the phenomena, it should not be thought of as the only way of understanding it and the future of science will change it's paradigms more often than some may want. The mathematical description of the theory should be attempting to describe this "mental picture" we have developed of these "forces" but do not be surprised when an experiment changes the results of some of the theory the paradigm is radically modified to account for these perceived conceptual anomalies.
I agree 100%.
As an additional point... There is very little differentiating "virtual" photons from "real" photons since photons can be created on demand and a sufficiently energetic process can produce these "real" photons from a source embedded in "virtual" photons... A radio transmitter is a source such as this... even the transitions in an atom can produce photons from virtual photons.
I'd say the difference between real photons and virtual photons is the difference between a swell wave and a bow wave. One travels, the other stands.
On the other hand it is still to be shown experimentally that gravitons really exist to enable the analogy between the photon and electromagnetism and the graviton and gravity to be extended into an overall paradigm.
There are no gravitons, Good Elf. Because a photon traveling through space causes gravity, and it's the only "particle" there. Have you seen How Long is a Photon? by Drozdov and Stahlhofen? See http://arxiv.org/abs/0803.2596.
Nice talking to you.
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Far, my understanding is that frame dragging occurs only if an object or particle is spinning. If the Earth had no rotation, an object placed anywhere on a sphere two hundred thousand kilometers from the Earth would experience the some magnitude and direction of acceleration as an object placed anywhere on that sphere.
That's my understanding too, Ron. I said it was like frame dragging. It isn't quite the same thing, but it is caused by spin. However this spin is in two dimensions, like a rotating steering wheel combined with a smoke ring:
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fmembers.optushome.com.au%2Fwalshjj%2Ftoroid2.jpg&hash=9863b12a9508b0640e13bd82db31ba21)
From "Is the electron a photon with a toroidal topology?", Williamson and van der Mark, Annales
de la Fondation Louis de Broglie, Volume 22, no.2, 133 (1997), see
http://www.cybsoc.org/cybcon2008prog.htm#jw for a copy.
Elf, Einstein spent the last thirty years of his life trying to unite electromagnetism and gravity. Some materials will block certain frequencies of the EM spectrum but no material, we know of, will block infrared. The best thermos bottle ever made, even with a complete vacuum, will have some infrared EM. There is no place in the Universe, man made or natural, where there is no radiation.
Agreed, Ron. Bodies radiate, and we all know that X-rays and gamma rays are very penetrative. Good Elf said "usually blocked" and I expect he was trying keep things simple. It's sometimes rather difficult to keep things simple.
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I would ask one question of Phys, can he show us one cubic nanometer of space that does not contain radiation in the Universe? If the answer is no then it could be said that radiation is the aether of space.
It could also be said that radiation is the unicorn of space. However, none of that would mean anything.
As Einstein points out clearly in his Leyden lecture, the basic ideas of an aether as an electromagnetic theory don't match our observations. Only if we have a very odd idea of an aether can we keep an idea of an aether. This odd idea is a manifold that can be represented using a four-dimensional pseudo-Riemannian geometry.
Anyone who wants to explain gravity now has to explain how their theory translates into the language of Riemannian geometry in such a way as to reproduce the observations that we have of the behaviour of gravity.
Several times I have asked Farsight to show how anything in his theory actually back up his claims of a) the size of the universe, b) the rotation curves of galaxies, c) the orbit of Mercury. He hasn't demonstrated anything in the way of being able to match these basic results of gravity theory. As such, I cannot accept that his theory is anything resembling science.
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Hi Farsight, Ron Hughes, Physbang et al,
I would ask one question of Phys, can he show us one cubic nanometer of space that does not contain radiation in the Universe? If the answer is no then it could be said that radiation is the aether of space
All radiation has a source and those sources are what you are referring to. There is no "background" of radiation acting as a kind of aether. Electromagnetic Radiation is not actually "seen" from afar ... what is "seen" is actually in your detector ... for instance your eye or the photographic plate in a telescope as an image. What is imaged there are "sources" not radiation per se... the regions from which the "light" originally came from. This process of "imaging" destroys the photons and converts them to other forms of energy.
The reason you "see" is because the photons are localized in the detectors such as your retina. In deep space where there are "virtually" no sources or sinks of radiation the radiation travels as an unconfined particle. What that means is the wave-function has "effectively" the same value everywhere in almost infinite space and when you do the sum ∫ψ2dv integrated over any reasonable volume of ostensibly empty space these values will be diminishingly small. That means the photons are phenomenologically "not there". Physics is all about phenomena and not philosophy. The phenomenon of "photons" is only near and around sinks (places where they may be absorbed) there the wave-function meets "barriers" which confine the photon and allow this function to be significantly positive... that is where it will be absorbed... especially if the site for the sink chosen is resonant with the source... It is a resonant "negotiation" between the source and sink like a transmission line.
If "light" of various frequencies is proposed as a aether and a reason for gravity then I know of no electromagnetic radiation not even gamma rays that would penetrate sufficiently into the earth to provide the impression that the earth was not hollow. Remember these "forces" must be reactive on the sources as much as on the sinks to allow for mutual "attraction". Too many photons are absorbed in the periphery of massive objects to allow EM radiation to be a candidate for "gravity". To electromagnetic radiations of every kind the earth would appear as a hollow shell because the force carriers (photons) could not penetrate sufficiently deeply to allow all the mass inside the earth to be "probed" and therefore allow the earth to be accurately "weighed". Gravity cannot be blocked (as far as we know)... not even partially... by any depth or density of material substance . That rules out electromagnetic radiation of all frequencies as a "background for the aether.
There are other forms of radiation (non-electromagnetic) such as neutrinos and they make a more plausible "aether" because of their immense ability to penetrate matter without being substantially absorbed.
It is an interesting point to ponder that aside from the fact that light travels at the speed of light and is simultaneously affected by electrodynamics and also by gravity and "falls" identically like a projectile along the "surface of spacetime" and is a "limiting case of material projectiles" as V -> C. This suggests there really is not action at a distance dependent on the mutual mass between particles since such a theory would mean that if one of the two "attractive" objects was of zero rest mass there would be no "attraction" at all. It is possible to demonstrate very effectively that photons have zero rest mass. So... photons "fall" like a very light stone that is traveling infinitely close to the speed of light.
Not quite, Good Elf! Maybe you were keeping it simple, but see that squared-off circle representing a single electron? It's deflected half as much as light:
←
↓ ↑
→
I was keeping it simple... It is only meant to relate to General Relativity so I am not dealing with charged species like an electron. The photon bears no nett charge and has no mass... an ideal object to illustrate this principle. I also assume that the manifold in General Relativity is curved only by the masses embedded in it and there are no fields in that space... we know fields affect light so I am also ignoring that as well.. Under those circumstances photons "fall" unseen like "projectiles" through space and are a limiting case of "ordinary" relativistic projectiles where v -> C. The point to note is while the photon has momentum it has no rest mass but "falls" in an identical manner to any other object with mass. Thus mass is not an attractor as it is in Newton's Theory and Einstein was right in saying Gravity was a pseudo-force. Otherwise light would not curve around massive objects such as in Einstein's first big test of GR and also the reason behind the frequently observed phenomenon of Einstein's Rings (http://en.wikipedia.org/wiki/Einstein_ring). This pseudo-force is clearly all down to simple curvature and the velocity and position of the particle no matter what it is. Now there are more complex interactions involved in the creation of electrons and this theory does not deal with that issue.
I note your point though... Clearly the photon does bear "topological charge"... the twisted strip model shows one way in which this "charge" in permanently charged particles may arise. This would go a long way to realizing JA Wheeler's "dream" of geometrodynamics...
As described by Wheeler in the early 1960s, geometrodynamics attempts to realize three catchy slogans
* mass without mass,
* charge without charge,
* field without field.
Already we have pretty convincingly shown that no particle in any place in our universe contains solitary magnetic monopoles so why do electric monopoles (charges) exist?? [:-\]... these entities are crucial to the current Standard Model... if no magnetic monopoles and all electric monopoles are simple topological charges then we have realized Wheeler's dream. JA Wheeler I would rate as the greatest physicist never to win a Nobel Prize. Not just for this but many great contributions... not the least of which was being RP Feynman's mentor in his crucial formative years when creating Absorber Theory... the fundamentals on which quantum electrodynamics was constructed which won Feynman a "gong".
The electron in the theory discussed in Williamson and Van der Mark's paper deals with a permanent topological charge in a very energetic optical vortex. These vortices may be created "in the wild" (recent papers have discussed the creation of these entities using simple holograms (http://www.physorg.com/news182957628.html)) and maybe they are stable quantum "resonant" entities with requisite properties of stability. It is possible to explain the charge using this model but it is more difficult to explain mass. This involves the difficult (and reversible) process of "sparking the vacuum"... creating electrons from raw photons. This has been done but it is still very difficult using present technology the electron carries a lot of energy. There is a much easier process of annihilation of the matter anti-matter "electrons" but all these events while complex are seamlessly time reversible.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.hep.princeton.edu%2F%7Emcdonald%2Fe144%2Fpair.gif&hash=1b5ae2c526e3438bc0ff9bc6016240b6)
Conjuring Matter From Light (http://www.hep.princeton.edu/~mcdonald/e144/science1202.html)
Speculation: Mass appears to be related to the Orbital Angular Momentum of the internal photon exhibiting as an "external" mass which is linked directly to the conservation laws of CPT symmetry.
Cheers
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Your comments noted, PhysBang. But it isn't "my theory". All I've done is researched genuine historical material and bona-fide peer-reviewed papers. Einstein really did talk of a non-constant guv that causes curvilinear motion along with the aether of general relativity. The modern interpretation of general relativity genuinely seems to paint a different interpretation to Einstein's, and mathematical exercises just don't assist our discussion.
Ron: I concur with Good Elf re electromagnetic radiation not being the "background". It's something deeper, as demonstrated by say the Aharanov-Bohm effect.
I was keeping it simple...
Noted, Good Elf. In my experience it's something like plastering a wall. It isn't easy to make it look easy.
I note your point though... Clearly the photon does bear "topological charge"... the twisted strip model shows one way in which this "charge" in permanently charged particles may arise. This would go a long way to realizing JA Wheeler's "dream" of geometrodynamics...
Yes, interesting bloke Wheeler. Yes, I'd say he was barking up the right tree. It's all in the geometry. But there's this subtle shift that's easy to miss.
The electron in the theory discussed in Williamson and Van der Mark's paper deals with a permanent topological charge in a very energetic optical vortex. These vortices may be created "in the wild" (recent papers have discussed the creation of these entities using simple holograms (http://www.physorg.com/news182957628.html)) and maybe they are stable quantum "resonant" entities with requisite properties of stability. It is possible to explain the charge using this model but it is more difficult to explain mass.
Interesting paper, the tying light in knots. I'm confident that:
The study of knotted vortices was initiated by Lord Kelvin back in 1867 in his quest for an explanation of atoms", adds Dennis, who began to study knotted optical vortices with Professor Sir Michael Berry at Bristol University in 2000. "This work opens a new chapter in that history."
..is not a casual comment. We should discuss mass at length, perhaps in a dedicated thread. We have so much to talk about!
Speculation: Mass appears to be related to the Orbital Angular Momentum of the internal photon exhibiting as an "external" mass which is linked directly to the conservation laws of CPT symmetry.
I don't see why you flag this as a speculation. Pair production and annihilation are bona-fide science, along with electron spin and angular momentum. We create mass from a massless photon, and we destroy it via electron/positron annihilation. You started with light travelling laterally at c conveying momentum, and you ended with light travelling laterally at c conveying momentum. In between you have inertia. Mass. The electron and positron are quite literally made from light, and the annihilation evidence says there's nothing else there. There's no evidence for any coupling with a new field. So I'd class the OAM relation where light couples with itself as the reasonable deduction, not the speculation.
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Your comments noted, PhysBang. But it isn't "my theory". All I've done is researched genuine historical material and bona-fide peer-reviewed papers.
No, it really is your theory because you are making claims about experiments and observations that contradict what every scientist who uses relativity theory claims. For example, you say that relativity theory, if used "correctly", will produce the right rotation curves for galaxies. However, every scientist working in astronomy and astrophysics says that this doesn't happen.
Einstein really did talk of a non-constant guv that causes curvilinear motion along with the aether of general relativity.
When you say this, you are obviously ignoring what Einstein said about the aether. You even ignore what the author of the page hosting your favourite link to Einstein's address says about that address. This author writes on the page, "This address has been frequently misunderstood as positing that a return of the ether theory." Anyone who reads the address or the page must see that Einstein is clearly rejecting the standard idea of an aether theory in favour of, at best, an idea that bears only one feature of an aether theory, that of being a medium.
The modern interpretation of general relativity genuinely seems to paint a different interpretation to Einstein's, and mathematical exercises just don't assist our discussion.
We are not talking about mathematical exercises, we are talking of the actual content of the theory. When you say that relativity theory does away with the need for dark matter, you are making a claim about actual values that are measured and actual values that are calculated. You have shown no way to reconcile these values. If you have a way to reconcile these values, you should share it. If you have no way to reconcile these values, you should retract your claims. You need to show exactly how "a non-constant guv that causes curvilinear motion along with the aether" produces the calculations for the rotation curve of a galaxy and how this calculation matches up with the observed rotation curve. An astronomer or an astrophysicist who makes a claim about dark matter backs up her or his claim with the relevant observations and calculations.
I note that you have retracted some of your previous claims. For example, you have removed your two calculations of the size of the universe from your public document version of your theory, two calculations that differed by several orders of magnitude. Many actual scientist retract claims when they have made an error. If your claims about dark matter are in error, it is no shame to retract them.
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No, it really is your theory because you are making claims about experiments and observations that contradict what every scientist who uses relativity theory claims. For example, you say that relativity theory, if used "correctly", will produce the right rotation curves for galaxies. However, every scientist working in astronomy and astrophysics says that this doesn't happen.
I'm not making claims that contradict relativity. We all know that Einstein missed the expansion of the universe, it's just a trivial matter of looking at what Einstein said about inhomogeneous space and then applying knowledge of the expanding universe. As for "every scientist", you should read Mordehai Milgrom's New Physics at Low Accelerations (MOND): an Alternative to Dark Matter at http://arxiv.org/abs/0912.2678. Note page 4 where he says:
"We see that the modification of GR entailed by MOND does not enter here by modifying the ‘elasticity’ of spacetime
(except perhaps its strength), as is done in f(R) theories and the like."
I've merely stated the obvious. Einstein told us that a gravitational field is a region of inhomogeneous space, and we all know of the raisins-in-the-cake analogy for the expanding universe. Space expands between the galaxies but not within, giving rise to another source of inhomogeneous space. According to Einstein, that's a gravitational field, with no causative matter. I really can't see why you have such a problem with this.
When you say this, you are obviously ignoring what Einstein said about the aether. You even ignore what the author of the page hosting your favourite link to Einstein's address says about that address. This author writes on the page, "This address has been frequently misunderstood as positing that a return of the ether theory." Anyone who reads the address or the page must see that Einstein is clearly rejecting the standard idea of an aether theory in favour of, at best, an idea that bears only one feature of an aether theory, that of being a medium.
I'm not obviously ignoring anything, I'm reporting what Einstein said. He talked about a non-constant guv that causes curvilinear motion, and he talked about the aether of general relativity. See http://www.zionism-israel.com/Albert_Einstein/Albert_Einstein_Ether_Relativity.htm. What more can I say? There it is, in black and white.
We are not talking about mathematical exercises, we are talking of the actual content of the theory. When you say that relativity theory does away with the need for dark matter, you are making a claim about actual values that are measured and actual values that are calculated. You have shown no way to reconcile these values. If you have a way to reconcile these values, you should share it. If you have no way to reconcile these values, you should retract your claims.
No I shouldn't. We have free speech in science, and observations and comments are permitted.
You need to show exactly how "a non-constant guv that causes curvilinear motion along with the aether" produces the calculations for the rotation curve of a galaxy and how this calculation matches up with the observed rotation curve.
As above.
An astronomer or an astrophysicist who makes a claim about dark matter backs up her or his claim with the relevant observations and calculations.
But even to this day, no astronomer or astrophysicist can provide conclusive proof for the existence of dark matter. It remains the subject of debate. And since it was first proposed by Zwicky seventy three years ago, we are surely free to discuss alternatives. People are discussing them more, and proposing experiments, see for example Testing MOND/TEVES with LISA Pathfinder by Christian Trenkel, Steve Kemble, Neil Bevis, and Joao Magueijo at http://arxiv.org/abs/1001.1303.
I note that you have retracted some of your previous claims. For example, you have removed your two calculations of the size of the universe from your public document version of your theory, two calculations that differed by several orders of magnitude. Many actual scientist retract claims when they have made an error. If your claims about dark matter are in error, it is no shame to retract them.
I haven't retracted anything. I never gave any calculations, I reported two numbers, a contradiction was pointed out, so I removed the contradiction. That was back in January 2008, see "last updates". And please can we stay on topic.
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As for "every scientist", you should read Mordehai Milgrom's New Physics at Low Accelerations (MOND): an Alternative to Dark Matter at http://arxiv.org/abs/0912.2678. Note page 4 where he says:
"We see that the modification of GR entailed by MOND does not enter here by modifying the ‘elasticity’ of spacetime
(except perhaps its strength), as is done in f(R) theories and the like."
Perhaps you failed to notice that this proposes a modification of GR. Do you propose a modification of GR?
I've merely stated the obvious. Einstein told us that a gravitational field is a region of inhomogeneous space, and we all know of the raisins-in-the-cake analogy for the expanding universe. Space expands between the galaxies but not within, giving rise to another source of inhomogeneous space. According to Einstein, that's a gravitational field, with no causative matter. I really can't see why you have such a problem with this.
The widely examined and accepted cosmological models are not relevant here. I have a problem with your claims because you are denying the facts. The facts are that the rotation curves of galaxies do not work out unless we include dark matter. Please show us, and the entire scientific community including Milgrom, how standard GR can produce the rotation curves of galaxies without the need for dark matter.
I'm not obviously ignoring anything, I'm reporting what Einstein said. He talked about a non-constant guv that causes curvilinear motion, and he talked about the aether of general relativity. See http://www.zionism-israel.com/Albert_Einstein/Albert_Einstein_Ether_Relativity.htm. What more can I say? There it is, in black and white.
Indeed it is. But somehow, you have it in your head that guv isn't exactly what everyone means when they speak of curved spacetime. It's like you are pointing at a picture from Picasso's blue period and telling everyone that the painting is done entirely in red paint.
We are not talking about mathematical exercises, we are talking of the actual content of the theory. When you say that relativity theory does away with the need for dark matter, you are making a claim about actual values that are measured and actual values that are calculated. You have shown no way to reconcile these values. If you have a way to reconcile these values, you should share it. If you have no way to reconcile these values, you should retract your claims.
No I shouldn't. We have free speech in science, and observations and comments are permitted.
You aren't entirely correct; we are not in a venue of free speech. For example, I was banned from this forum for saying true things about you that are relevant to understanding your position. At the risk of further banning, I will point out that your refusal to actually acknowledge the data that exists, as you are fee to do, should be taken as a symptom that you really do not understand anything in this field and that your claims are bogus.
An astronomer or an astrophysicist who makes a claim about dark matter backs up her or his claim with the relevant observations and calculations.
But even to this day, no astronomer or astrophysicist can provide conclusive proof for the existence of dark matter. It remains the subject of debate. And since it was first proposed by Zwicky seventy three years ago, we are surely free to discuss alternatives. People are discussing them more, and proposing experiments, see for example Testing MOND/TEVES with LISA Pathfinder by Christian Trenkel, Steve Kemble, Neil Bevis, and Joao Magueijo at http://arxiv.org/abs/1001.1303.
If we look at that paper, we see attempts to reconcile different theories to the various observations though comparisons of predictions and measurements. This is, again, something you refuse to do. This is what makes it plain that your position is not a scientific one but one not far from fiction.
I note that you have retracted some of your previous claims. For example, you have removed your two calculations of the size of the universe from your public document version of your theory, two calculations that differed by several orders of magnitude. Many actual scientist retract claims when they have made an error. If your claims about dark matter are in error, it is no shame to retract them.
I haven't retracted anything. I never gave any calculations, I reported two numbers, a contradiction was pointed out, so I removed the contradiction. That was back in January 2008, see "last updates". And please can we stay on topic.[/quote]
This is very much on topic, as your refusal to acknowledge the facts here highlights your refusal to engage the science in an honest and open manner. You certainly derived one value, writing, "The universe is larger than the Compton wavelength of a proton by a factor of 10^40. That’s why gravity is weaker by a factor of 10^40." Here you were attempting to use the matching of mathematical results to support your theory, something you refuse to do with your claims about dark matter. When if became obvious that you contradicted yourself by several orders of magnitude, you removed the statement and now you say that you haven't retracted anything. Either you still endorse this derivation or you have retracted this derivation. Either you accept that mathematical results are important in science or you do not.
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The widely examined and accepted cosmological models are not relevant here. I have a problem with your claims because you are denying the facts. The facts are that the rotation curves of galaxies do not work out unless we include dark matter. Please show us, and the entire scientific community including Milgrom, how standard GR can produce the rotation curves of galaxies without the need for dark matter.
There is one way Phys, if the equation F = ma is not the same in all frames of reference.
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Perhaps you failed to notice that this proposes a modification of GR. Do you propose a modification of GR...
Not at all. I report Einstein's statements: a gravitational field is a region of inhomogeneous space caused by a concentration of energy tied up the matter of a planet, which in turn causes the curvilinear motion that is described as curved space-time. I don't deny the facts of general relativity, I report them. They're as described by Einstein, and they are validated by experiment. I'm sorry they're not as you wish them to be, and I'm sorry that the non-uniform expansion of the universe clearly offers another causative agent for inhomogeneous space which dispenses with the need for dark matter. I know it's distressing to you, but after 77 years without validation, dark matter has had its day, and science must progress.
I would urge you to consider Einstein's inhomogeneous space in the light of this statement:
"We see that the modification of GR entailed by MOND does not enter here by modifying the ‘elasticity’ of spacetime (except perhaps its strength), as is done in f(R) theories and the like."
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I report Einstein's statements: a gravitational field is a region of inhomogeneous space caused by a concentration of energy tied up the matter of a planet, which in turn causes the curvilinear motion that is described as curved space-time.
Einstein did not write or say this anywhere.
I don't deny the facts of general relativity, I report them.
When you say that GR can account for rotation curves without dark matter, you are denying the facts. Anyone who reads the links about MOND you have provided can easily tell this. You could easily prove that all the authors you cite are incorrect with a few calculations. Your refusal bears on your behaviour in general and the character of the theories you offer.
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I like this thread and hope no one gets banned from it. As a practicing lay-person myself, I find such exchanges useful, if not always edifying. Can I throw a pebble into the pond and to see if any interference patterns evolve?
Specifically, General Relativity seems to predict infinite singularities in black holes, but infinities do not exist in our universe. I do not see this as all that alarming. After all, the same sort of thing happened to Newton regarding the weird orbit of Mercury. Now we have another weird phenomenon to think about.
Opinion requested: is (are) additional dimensions outside of, but including, space time considered reasonable possibilities for examination? I am thinking of Vehn diagrams. A single dimension is included in two dimension which is included in three dimensions which is included in four dimensions etc.
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litespeed: general relativity itself doesn't predict the central black hole singularity. Instead the Misner/Thorne/Wheeler "geometrical interpretation" does. See http://www.mathpages.com/rr/s7-02/7-02.htm and note this bit:
Incidentally, I should probably qualify my dismissal of the "frozen star" interpretation, because there's a sense in which it's valid, or at least defensible. Remember that historically the two most common conceptual models for general relativity have been the "geometric interpretation" (as exemplified by Misner/Thorne/Wheeler's "Gravitation") and the "field interpretation" (as in Weinberg's "Gravitation and Cosmology"). These two views are operationally equivalent outside event horizons, but they tend to lead to different conceptions of the limit of gravitational collapse. According to the field interpretation, a clock runs increasingly slowly as it approaches the event horizon (due to the strength of the field), and the natural "limit" of this process is that the clock just asymptotically approaches "full stop" (i.e., running at a rate of zero) as it approaches the horizon. It continues to exist for the rest of time, but it's "frozen" due to the strength of the gravitational field. Within this conceptual framework there's nothing more to be said about the clock's existence. This leads to the "frozen star" conception of gravitational collapse.
I'd say additional dimensions are OK so long as they're dimensions of measure rather than dimensions that offer freedom of motion. For example we have three dimensions of space through which we can move, but we aren't free to move through the time dimension.
Physbang: see http://www.zionism-israel.com/Albert_Einstein/Albert_Einstein_Ether_Relativity.htm
"According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that “empty space” in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν).."
Einstein said this in 1920, and he talked about curvilinear motion in The Foundation of the General Theory of Relativity in 1916. The theory I offer is Einstein's relativity. I'm not denying the facts.
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Physbang: see http://www.zionism-israel.com/Albert_Einstein/Albert_Einstein_Ether_Relativity.htm
"According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that “empty space” in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν).."
Einstein said this in 1920, and he talked about curvilinear motion in The Foundation of the General Theory of Relativity in 1916. The theory I offer is Einstein's relativity. I'm not denying the facts.
This is another example of you cherry-picking quotations. Academics tend to call such behaviour dishonest.
Let's begin with the first sentence of the paragraph, the sentence that you failed to copy:
"Mach’s idea finds its full development in the ether of the general theory of relativity."
This makes it clear that what Einstein is talking about in his paragraph is an idea of Mach, in particular, that that aspect of physics that imparts the properties of inertia to objects is also influenced by these objects.
You are also cherry-picking by ignoring the actual cosmological models designed and endorsed by Einstein throughout his life. You are trying to make the point that it is wrong to ever consider anything to be homogeneous and isotropic in GR, but by ignoring all of Einstein's science and focusing on a single passage from an address out of context, you merely promote ignorance.
If you think that there is a case for GR to account for dark matter, then make the case with the actual observations and calculations of the science, don't cherry-pick statements from Einstein taken from a popular lecture and paste them out of context.
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I'm not cherry picking, PhysBang. You said Einstein didn't say that stuff about inhomogeneous space etc. But he did. I'm not promoting ignorance, I'm promoting knowledge. I've given you the link, and out of context just doesn't wash. He said what he said.
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PhysBang, let's keep ad hominems out of the forum. Such as accusations of dishonesty and promoting ignorance.
Talk to the facts, and only the facts, such as those on public record. Offer your interpretation, if you wish, be specific, then let the readers decide for themselves if there is any distortion going on.
Thank you.
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PhysBang, let's keep ad hominems out of the forum. Such as accusations of dishonesty and promoting ignorance.
To commit an ad hominem is to perform an ignotario elenchi argument. That is, it is to bring up facts irrelevant to the matter at hand. I have done no such thing. It is relevant to understanding Farsight's claims that one understand that he is presenting a small subset of the available literature, out of context, in such a way that a reader might be mislead. It is also relevant for a reader to know that Farsight has been made aware of the misleading nature of his presentation and that he continues to present his claims in this manner.
Talk to the facts, and only the facts, such as those on public record. Offer your interpretation, if you wish, be specific, then let the readers decide for themselves if there is any distortion going on.
Part of addressing the facts is to actually show how these facts are presented. In this case, I have to somehow demonstrate that what Farsight is offering is not actually relevant to the points that he wants to make. If Farsight would offer something to work with, namely scientific arguments to back up his scientific claims, then I could engage in an analysis of the facts.
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By ad hominem, I simply refer to your character attacks, again, such as your referring to his "dishonesty and promoting ignorance", or "you really do not understand anything in this field."
You did a good job of largely avoiding that in your reply directly above, which expresses and re-states your technical objections, but without the mudslinging.
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Physbang: I'm afraid it isn't a small subset of the available literature. In 1911 Einstein wrote a paper "On the Influence of Gravitation on the Propagation of Light" where he said "If we call the velocity of light at the origin of co-ordinates c0, then the velocity of light c at a place with the gravitation potential Φ will be given by the relation c = c0 (1 + Φ/c²).". See http://www.relativitybook.com/resources/Einstein_gravity.html for an online version.
In 1912 he wrote "On the other hand I am of the view that the principle of the constancy of the velocity of light can be maintained only insofar as one restricts oneself to spatio-temporal regions of constant gravitational potential". I’ve got this page as a PDF image, I’ll have to check where it’s from. Similarly in 1913 he wrote "I arrived at the result that the velocity of light is not to be regarded as independent of the gravitational potential".
In 1915 he wrote "However the writer of these lines is of the opinion that the theory of relativity is still in need of generalization, in the sense that the principle of the constancy of the velocity of light is to be abandoned." This is on page 259 of Doc 21.
I’ve already given information from chapter 22 of Relativity: The Special and General Theory written in 1916 where Einstein refers to the postulate of special relativity. I’ve got a page showing the original German, where Einstein says die Ausbreitungsgeschwindigkeit des Lichtes mit dem Orte variiert. Get a German friend to translate it and he will confirm the google translation the speed of light varies with the locality (http://translate.google.com/#de|en|die%20Ausbreitungsgeschwindigkeit%20des%20Lichtes%20mit%20dem%20Orte%20variiert). It’s backed up by the actual scientific evidence of for example the GPS clock adjustment. A GPS clock employs microwaves. That’s light. The clock runs slower because the light moves slower. There’s also the Shapiro delay (http://en.wikipedia.org/wiki/Shapiro_delay). It’s a delay, the light moves slower when it passes the limb of the sun. The wiki article on the Shapiro delay even includes the quote from Chapter 22:
"In the second place our result shows that, according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity and to which we have already frequently referred, cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position. Now we might think that as a consequence of this, the special theory of relativity and with it the whole theory of relativity would be laid in the dust. But in reality this is not the case. We can only conclude that the special theory of relativity cannot claim an unlimited domain of validity ; its results hold only so long as we are able to disregard the influences of gravitational fields on the phenomena (e.g. of light)."
All you have to do is look at the original material to understand that the modern interpretation of relativity is different to Einstein’s, and appreciate that this then causes misunderstanding. As an example of this, read Is The Speed of Light Constant? (http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html) on the Baez website by Gibbs and Carlip, and look at the section on General Relativity. You see the chapter 22 quote again along with the comment “Since Einstein talks of velocity (a vector quantity: speed with direction) rather than speed alone, it is not clear that he meant the speed will change, but the reference to special relativity suggests that he did mean so. This interpretation is perfectly valid and makes good physical sense, but a more modern interpretation is that the speed of light is constant in general relativity.” Lower down the article says “ Finally, we come to the conclusion that the speed of light is not only observed to be constant; in the light of well tested theories of physics, it does not even make any sense to say that it varies.”. Hence the article says Einstein’s variable speed of light makes sense, and doesn’t make sense.
All of this isn’t out of context, it’s conclusive.
demografx: thank you for your moderation.
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Physbang: I'm afraid it isn't a small subset of the available literature. In 1911 Einstein wrote a paper "On the Influence of Gravitation on the Propagation of Light" where he said "If we call the velocity of light at the origin of co-ordinates c0, then the velocity of light c at a place with the gravitation potential Φ will be given by the relation c = c0 (1 + Φ/c²).". See http://www.relativitybook.com/resources/Einstein_gravity.html for an online version.
Why, if you want to defend a point about general relativity, are you looking at things Einstein wrote before general relativity?
Since you seem to want to use the 1911 theory as representative of Einstein's theory, please show us using this theory where Einstein uses an aether. Additionally, please show us how one can use the 1911 theory to calculate the rotation curves of galaxies. It would be nice if you could also show how this use gets rid of the measurements of the amount of dark matter.
All you have to do is look at the original material to understand that the modern interpretation of relativity is different to Einstein’s, and appreciate that this then causes misunderstanding.
OK, so please demonstrate how, using the 1911 theory or the later theory, the rotation curve of a galaxy doesn't produce a measurement of dark matter.
Hence the article says Einstein’s variable speed of light makes sense, and doesn’t make sense.
A discerning reader should note that the authors write, "In general relativity, the appropriate generalisation is that the speed of light is constant in any freely falling reference frame (in a region small enough that tidal effects can be neglected). In this passage, Einstein is not talking about a freely falling frame, but rather about a frame at rest relative to a source of gravity. In such a frame, the speed of light can differ from c, basically because of the effect of gravity (spacetime curvature) on clocks and rulers." Thus one notes that the authors are pointing out that in the particular passage of Einstein that they quote, Einstein is using an improper generalization. What makes one generalization proper and the other improper is that the proper generalization recognizes the role that light has in determining the causal structure of events. AS the authors note, the constant speed of light is fundamental to the way that general relativity determines causal structure. Thus it is conceptually more fundamental than the time it takes for light to cross a certain distance in a certain time in a certain particular system of coordinates. This is particularly true since the correct description of any physical system in any well-formed set of coordinates in general relativity must maintain this causal structure.
The most well known system of coordinates in general relativity with what one might call a variable speed of light is that associated with the Friedmann equations. These equations provide a solution to the Einstein field equation and the form the basis of a family of cosmological models preferred by Einstein after 1929 and survive in a modified version in contemporary cosmology. In these solutions, light can travel faster than light, because over time the distance between where the light left and where the light is received can get larger. However, one should recognize that this is not a way to measure speed that is representative of the causal structure of the universe and when one takes that into account properly, one finds the speed of light as constant. Despite working with, and accepting as approximately correct, the Friedmann models, cosmologists do not run around saying that the speed of light is variable.
All this is clear from not simply cherry-picking particular parts of the document and from looking at the authors' claims in context.
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Why, if you want to defend a point about general relativity, are you looking at things Einstein wrote before general relativity?
To demonstrate that I'm not cherry picking. We see Einstein repeatedly telling us the speed of light is variable.
Since you seem to want to use the 1911 theory as representative of Einstein's theory, please show us using this theory where Einstein uses an aether.
I don't. Plus I've already shown you the 1920 Leyden Address where Einstein talks of the aether of General Relativity.
OK, so please demonstrate how, using the 1911 theory or the later theory, the rotation curve of a galaxy doesn't produce a measurement of dark matter.
I politely decline on the grounds that such a laborious exercise is unnecessary in the light of Einstein's description of a gravitational field as inhomogeneous space, along with our current knowledge of the expansion of the universe. Space expands between the galaxies, not within. The result is inhomogeneous space, and that's a gravitational field with no causative matter.
...As the authors note, the constant speed of light is fundamental to the way that general relativity determines causal structure.
It is at odds with Einstein, who described the central concentration of energy tied up in as the matter of a planet causing a conditioning of the surrounding space described via a non-constant gμv which causes a variable speed of light that then causes the curvilinear motion that is described as curved spacetime. I've paraphrased, but read the original material, and you will find that I am correct.
Thus it is conceptually more fundamental than the time it takes for light to cross a certain distance in a certain time in a certain particular system of coordinates. This is particularly true since the correct description of any physical system in any well-formed set of coordinates in general relativity must maintain this causal structure.
No, I'm afraid it isn't. What's conceptually more fundamental relates to what we actually observe. We don't observe time passing, our seconds are defined using the motion of light. Thus when our second changes, it's because the rate of motion of light has changed.
The most well known system of coordinates in general relativity with what one might call a variable speed of light is that associated with the Friedmann equations. These equations provide a solution to the Einstein field equation and the form the basis of a family of cosmological models preferred by Einstein after 1929 and survive in a modified version in contemporary cosmology.
Noted.
In these solutions, light can travel faster than light, because over time the distance between where the light left and where the light is received can get larger. However, one should recognize that this is not a way to measure speed that is representative of the causal structure of the universe...
No, of course not. There are galaxies receding from us at more than c due to the expansion of the universe, but we do not consider them to be actually moving at more than c.
..and when one takes that into account properly, one finds the speed of light as constant.
I'm afraid one doesn't. One only "finds the speed of light to be constant" when one employs the motion of light to define one's seconds and metres to then measure the speed of light. It isn't constant, Einstein said it, gravitational time dilation is scientific fact, and our best clocks are atomic clocks which count microwave peaks. Those clocks run slower when the light moves slower. The scientific evidence is there, and "when one takes that into account properly" in no way counters it.
Despite working with, and accepting as approximately correct, the Friedmann models, cosmologists do not run around saying that the speed of light is variable.
But I'm afraid some do. See for example http://en.wikipedia.org/wiki/Variable_speed_of_light and http://arxiv.org/PS_cache/arxiv/pdf/0705/0705.4507v1.pdf where Magueijo and Moffat responded to Ellis. Its constancy has become a tautology.
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Phys, does the rotation curve of galaxies guarantee the existence of dark matter? I would think that a logical mind must realize there is the possibility of another explanation even that one of our fundamental tenets may be wrong.
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One more question phys and I will explain after your answer. Suppose that the result of the BB was the creation of a single proton and no other particles, how much space would be created for that proton?
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Phys, does the rotation curve of galaxies guarantee the existence of dark matter? I would think that a logical mind must realize there is the possibility of another explanation even that one of our fundamental tenets may be wrong.
The rotation curves of galaxies are one piece of evidence for dark matter among many. If one wants to demonstrate an alternative to dark matter, one has to address the evidence. Traditionally, alternative hypotheses to dark matter have found the galaxy rotation curves the easiest piece of evidence to account for, but have had problems with the rest.
Simply imagining a different possibility is not enough to claim that existing science is wrong. If one wants to say that the work of practising astronomers is incorrect, one should demonstrate this.
One more question phys and I will explain after your answer. Suppose that the result of the BB was the creation of a single proton and no other particles, how much space would be created for that proton?
Well, given the standard model, it looks like there could be any amount of space created for that particle. This depends on other initial conditions, primarily the rate of expansion in the space of the universe. That rate can only be so high in a finite universe. If the universe is finite in size, then it could have a maximum radius and collapse on itself, again depending on the initial condition that sets the rate of expansion.
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To demonstrate that I'm not cherry picking. We see Einstein repeatedly telling us the speed of light is variable.
Picking statements from wildly different theories to say that the speed of light is variable in GR is a perfect example of cherry-picking. You are taking quotations out of their original context and using them to support a point about a significantly different context.
Since you seem to want to use the 1911 theory as representative of Einstein's theory, please show us using this theory where Einstein uses an aether.
I don't. Plus I've already shown you the 1920 Leyden Address where Einstein talks of the aether of General Relativity.
So you admit that you reject the theory of 1911 in which Einstein says that the speed of light is variable. Good. Now you can simply show us how to properly calculate the rotation curves of galaxies in GR.
I politely decline on the grounds that such a laborious exercise is unnecessary in the light of Einstein's description of a gravitational field as inhomogeneous space, along with our current knowledge of the expansion of the universe. Space expands between the galaxies, not within. The result is inhomogeneous space, and that's a gravitational field with no causative matter.
It is not unnecessary, because every astronomer working with dark matter uses GR to calculate rotation curves. You are saying that they are doing this incorrectly. Why do you dismiss their work if you are not willing to point out what they are doing wrong? These people are using gμv like any other scientist. Are you claiming that these astronomers are simply lying about their results?
It is at odds with Einstein, who described the central concentration of energy tied up in as the matter of a planet causing a conditioning of the surrounding space described via a non-constant gμv which causes a variable speed of light that then causes the curvilinear motion that is described as curved spacetime. I've paraphrased, but read the original material, and you will find that I am correct.
I have read the original material and I note that you are incorrect. You are incorrect because you are continuing to ignore exactly what the authors of the page you cited explain.
No, I'm afraid it isn't. What's conceptually more fundamental relates to what we actually observe. We don't observe time passing, our seconds are defined using the motion of light. Thus when our second changes, it's because the rate of motion of light has changed.
If you can make a theory out of these claims, then demonstrate it with a simple example. For example, using your theory, calculate the rotation curve of a galaxy. Alternately, calculate the perihelion shift of Mercury.
Despite working with, and accepting as approximately correct, the Friedmann models, cosmologists do not run around saying that the speed of light is variable.
But I'm afraid some do. See for example http://en.wikipedia.org/wiki/Variable_speed_of_light and http://arxiv.org/PS_cache/arxiv/pdf/0705/0705.4507v1.pdf where Magueijo and Moffat responded to Ellis. Its constancy has become a tautology.
This is another example of cherry-picking. Magueijo and Moffat do not support anything like your theory, nor do they use the fact that there is expansion in the Friedmann models as evidence for the variable speed of light. As evidence, we can see that they discuss VSL theories as alternatives to GR, not as interpretations of GR. Additionally, they note "The c in VSL theories is never a
coordinate speed of light. It is the physical speed of light measured by free-falling observers and cannot be undone by a coordinate transformation." (pg. 3) This is a fundamental different in determinations of speeds that was expressed in Gibbs and Carlip's article that you apparently fail to understand: Einstein's variable speed of light in the quotation is a coordinate speed, not that speed measured by free-falling observers. It is this latter speed that one should use as the basis of generalizations, not the speed in a particular coordinate system. It is this latter speed that determines the causal structure of events, not the speed in a coordinate system.
You are welcome to come up with your own theory and test it against the evidence, but you should not try to use Einstein in some kind of ham-fisted argument from authority in lieu of providing evidence.
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Notice:
This topic will relocated to "New Theories".
Geezer (Mod)
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Phys, I would say that space in my single proton Universe, at the instant of the proton's creation, would start expanding at C because the electric field of the proton would start creating space at C.
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I've given you ample Einstein quotes PhysBang, enough to demonstrate that I'm clearly not cherry-picking, and the hoary old "out of context" does not undo what Einstein actually said. We all know that the 1911 theory was incomplete, just as we know that not all cosmologists examining gravitational anomalies support the dark matter hypothesis, just as we know that there are cosmologists who do walk around talking about the variable speed of light. This isn't a "my theory" issue, this is Einstein's theory. If you'd really read the original, you'd have read "the principle of the constancy of the velocity of light is to be abandoned." Dismissing Einstein is no substantive argument.
Here's the deal re dark matter, as simply as I can put it: it's energy that causes gravity, not matter. Matter only causes gravity because of the energy content. Einstein told us that a gravitational field has energy, and that a gravitational field is a region of inhomogeneous space. Now take a region of homogeneous space and divide it into cubes. Now decrease the energy-density of all of the cubes bar the one in the centre. The result? An energy-density gradient all around it. A gravitational field. But try as you might, when you look in that central cube, there's not a single speculative WIMP, there's no dark matter there. Because the dark matter you're looking for, is space itself. It's dark, it has energy, it isn't moving with respect to you, and E=mc2.
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My gedanken about the single proton should be enormously important for anyone who thinks about it's meaning. THE EXPANDING ELECTRIC FIELD OF THE PROTON IS THE AETHER OF SPACE . When all the electrons and protons were created their expanding electric fields created space at C.
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I've given you ample Einstein quotes PhysBang, enough to demonstrate that I'm clearly not cherry-picking, and the hoary old "out of context" does not undo what Einstein actually said.
The statement "out of context" is surely old to you because you keep using the same flawed technique to try to make your case. Your continuing behaviour of taking things out of context does nothing to change any of the science that Einstein and others published. If you want to actually address the content of the science, we'll all be waiting.
Here's the deal re dark matter, as simply as I can put it: it's energy that causes gravity, not matter. Matter only causes gravity because of the energy content. Einstein told us that a gravitational field has energy, and that a gravitational field is a region of inhomogeneous space. Now take a region of homogeneous space and divide it into cubes. Now decrease the energy-density of all of the cubes bar the one in the centre. The result? An energy-density gradient all around it. A gravitational field. But try as you might, when you look in that central cube, there's not a single speculative WIMP, there's no dark matter there. Because the dark matter you're looking for, is space itself. It's dark, it has energy, it isn't moving with respect to you, and E=mc2.
OK, so, please, do the calculation for just one galaxy that astronomers use as evidence for dark matter and show people wrong based on scientific evidence. You are trying to say that every textbook, and pretty much every equation in every textbook, on this subject is wrong. You can easily prove your point by doing one simple example.
We are all waiting.
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My gedanken about the single proton should be enormously important for anyone who thinks about it's meaning. THE EXPANDING ELECTRIC FIELD OF THE PROTON IS THE AETHER OF SPACE . When all the electrons and protons were created their expanding electric fields created space at C.
What you have written fails to be a gedanken experiment because it fails to elicit gedanken. You make some claims, but I have no idea what they could possibly mean.
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If you can't understand it nothing in the Universe can make you understand.