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Author Topic: How much do all of the electrons on Earth weigh?  (Read 11455 times)

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How much do all of the electrons on Earth weigh?
« on: 20/06/2009 04:17:41 »
What is the separate particle mass total for the earth's mass?
i.e.  quark  ?%
      electron   ?%
« Last Edit: 26/08/2009 13:46:53 by chris »


 

Offline labview1958

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Re: How much do all of the electrons on Earth weigh?
« Reply #1 on: 19/08/2009 12:48:20 »
Is it possible to create particles from plain energy? Reversing Einstein equation. m = E/c2.
 

Offline syhprum

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Re: How much do all of the electrons on Earth weigh?
« Reply #2 on: 19/08/2009 13:01:22 »
The mass of the main constituents of matter Protons and Neutrons derives from the Quarks and the binding energy of the Gluon's this is still controversial but it is believed that the binding energy of the Guons forms the greater contribution.
Electrons having a mass of 1/1836 that of a Proton are a minor contributor.
The mass of the earth is approximately 6*10^24 Kg so you can do the arithmetic.

http://www2.slac.stanford.edu/vvc/theory/quarks.html
« Last Edit: 19/08/2009 20:09:54 by syhprum »
 

Offline Vern

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Re: How much do all of the electrons on Earth weigh?
« Reply #3 on: 19/08/2009 17:24:06 »
We seem to be moving away from the concept of mass as a system. This I suspect is bad. My concept of mass is that it is a system consisting of the combination of the movement of energy fields. The fields may be bound in particles we like to call electrons, protons, neutrons, and  maybe even quarks. This is just my speculation. But, if you take away the electromagnetic fields, you take away all of the mass. So it is difficult to imagine "rest mass". Maybe all of massiveness is really only relative movement.
 

Offline Farsight

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Re: How much do all of the electrons on Earth weigh?
« Reply #4 on: 19/08/2009 18:04:34 »
Not quite, Vern. Put a photon inside a mirrored box. It exhibits no electric field, but the mass of the system has increased. IMHO it's better to think of "rest mass" as energy that is not moving in aggregate with respect to you. Essentially it's "rest energy", even though the photon is not actually at rest. Alternatively think of inertia as exhibiting a symmetry with momentum. If it's the photon moving, it's got momentum p=hf/c. If however it isn't moving in aggregate with respect to you, what you measure is mass. And of course to make a photon not move in aggregate with respect to you (at least not much) we use pair production, so creating mass and charge. To reverse the process, we use annihilation. Only in between these two events, we don't talk of photons, we talk of electrons and positrons. This is no speculation, this is experimental fact. I've now come to feel that pair production is like a hole in the heart of physics. Nobody has previously explained what's happening, and it seems that nobody has thought it important. Of course, the confusion and ambiguity surrounding the word mass doesn't help either.
 

Offline Vern

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Re: How much do all of the electrons on Earth weigh?
« Reply #5 on: 19/08/2009 19:07:20 »
What is a photon if not electromagnetic field? I have always seen photons explained as waves of changing electric and magnetic amplitude. I speculate that the electric and magnetic fields that comprise photons always go to saturation at two single points. This saturation property gives rise to quantum phenomena.
 

Offline Nizzle

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Re: How much do all of the electrons on Earth weigh?
« Reply #6 on: 20/08/2009 05:47:53 »
Mass is interaction of particles with the Higgs field
 

Offline Farsight

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Re: How much do all of the electrons on Earth weigh?
« Reply #7 on: 20/08/2009 08:43:15 »
What is a photon if not electromagnetic field? I have always seen photons explained as waves of changing electric and magnetic amplitude. I speculate that the electric and magnetic fields that comprise photons always go to saturation at two single points. This saturation property gives rise to quantum phenomena.
It's an electromagnetic wave, Vern. Yes, there's electromagnetic field in there, it's varying in a sinusoidal fashion, hence there has to be an alternating current. But when we talk of waves and amplitude we don't say that the amplitude is changing as the wave passes by. The amplitude is the peak-to-trough measure. Look at a picture of the electromagnetic spectrum: 



What do you see? A common amplitude. The amplitude is always the same

As to what it really is, the clues are scattered throughout history and in the evidence. You and Robert Kemp have found some I know, but for the life of me I don't understand why it's speculation and why none of it is in the curriculum: the photon conveys energy, and the dimensionality of energy is stress x volume. See Einstein's stress-energy-momentum tensor and think of space and pressure. See Minkowski's Space and Time where he talks about a wrench. Everybody misses this, but he's talking about the thread of a screw: think of the right hand-rule and imagine gripping a reamer or drill bit and pushing it up with your thumb. The electric field is analogous to the twist, the magnetic field is analagous to the turn. So think of the photon as a pressure pulse, and the shape of it is the integral of the sinusoidal electric waveform, because that's giving you the slope. Now think p=hf/c, see Planck's constant of action and note where it says: The dimensions may also be written as momentum multiplied by distance. See the original Maxwell and note his displacement current and his electric elasticity equation E=1/ε D. Now look at pair production and the electron's Compton wavelength of 2.426 x 10-12m. That amplitude is a kind of saturation, but it's also a kind of elastic limit. And underlying it is a geometrical spatial extension, like a Weyl gauge-change. The common photon amplitude is a distance. Divide by 2π for the double-wrapped photon and it's 3.86 x 10-13m. That's the quantum of quantum mechanics. People say the gravitational field is curved spacetime, but that's the effect, not the cause. And what they miss, is that the electric field is curved space.

 

Offline labview1958

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Re: How much do all of the electrons on Earth weigh?
« Reply #8 on: 20/08/2009 10:17:29 »
If a photon slows down does it become heavier? E=mc2. If m goes up then c comes down to keep E constant.
 

Offline Nizzle

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Re: How much do all of the electrons on Earth weigh?
« Reply #9 on: 20/08/2009 11:59:22 »
If a photon slows down does it become heavier? E=mc2. If m goes up then c comes down to keep E constant.

Or maybe the photon will have less energy when it slows down and it's mass stays constant  ;)
 

Offline Vern

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Re: How much do all of the electrons on Earth weigh?
« Reply #10 on: 20/08/2009 13:50:33 »
Quote from: Farsight
As to what it really is, the clues are scattered throughout history and in the evidence. You and Robert Kemp have found some I know, but for the life of me I don't understand why it's speculation and why none of it is in the curriculum: the photon conveys energy, and the dimensionality of energy is stress x volume.
So you are the Farsight I know from other places :) Good to see you here! I think we mostly agree about the photon construct. Too bad we haven't come up with some great principal that will make this view of nature useful for predicting experimental outcomes.
 

Offline Vern

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Re: How much do all of the electrons on Earth weigh?
« Reply #11 on: 20/08/2009 13:55:08 »
Quote from: Nizzle
Or maybe the photon will have less energy when it slows down and it's mass stays constant  ;)
I think the consensus now is that the photon never really slows down. It simply follows a longer path to traverse certain materials. Maybe it is absorbed and re emitted by crystalline structures within materials etc.   
 

Offline Vern

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Re: How much do all of the electrons on Earth weigh?
« Reply #12 on: 20/08/2009 14:36:58 »
Quote from: Nizzle
Mass is interaction of particles with the Higgs field.
The Higgs field is speculation at present. I suspect it will never be discovered. My own speculation is that mass is simply electromagnetic change. Any time you confine electromagnetic change within a system you give mass to the system.
 

Offline Farsight

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Re: How much do all of the electrons on Earth weigh?
« Reply #13 on: 21/08/2009 14:16:56 »
If a photon slows down does it become heavier? E=mc2. If m goes up then c comes down to keep E constant.
Not quite, because E=mc2 doesn't apply to a photon, we say E=hf instead. But broadly speaking, you're right. See "the Weight of Light" concerning Robert Pound and Glen Rebka: http://focus.aps.org/story/v16/st1. The frequency of the photon increases because c decreases. The energy stays the same. 

So you are the Farsight I know from other places :) Good to see you here! I think we mostly agree about the photon construct. Too bad we haven't come up with some great principal that will make this view of nature useful for predicting experimental outcomes.
Yep, that's me Vern, and yes I think we're talking the same language. I mention you and Photon Theory in my acknowledgements for Particles Explained, along with Robert Kemp re the common amplitude. But don't say too bad too soon. I've maybe got a couple of great principles. We'll see, and I think we're getting there. Good to see you here.

I think the consensus now is that the photon never really slows down. It simply follows a longer path to traverse certain materials.
I'd go along with that. In glass it's following a more convoluted path.

Everybody: Vern is one of my "unsung heroes of science". He and others have been on the right lines for years, but IMHO people tend to resist new ideas, and underestimate just how much competition and rivalry there is in physics. In the fullness of time I hope we come to realise just how much this has hampered scientific progress. 
« Last Edit: 21/08/2009 14:35:41 by Farsight »
 

Offline Nizzle

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Re: How much do all of the electrons on Earth weigh?
« Reply #14 on: 21/08/2009 14:20:05 »
Yea, if you use E=mc² on a photon with mass 0, you'll get E=0...

 

Offline lightarrow

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Re: How much do all of the electrons on Earth weigh?
« Reply #15 on: 21/08/2009 20:28:45 »
But broadly speaking, you're right. See "the Weight of Light" concerning Robert Pound and Glen Rebka: http://focus.aps.org/story/v16/st1. The frequency of the photon increases because c decreases. The energy stays the same.
I'm sorry, what you say is wrong. The frequency increases because the energy increases. c stays constant.

See for example:
http://archive.ncsa.illinois.edu/Cyberia/NumRel/EinsteinTest.html
Quote
Gravitational Redshift
According to General Relativity, the wavelength of light (or any other form of electromagnetic radiation) passing through a gravitational field will be shifted towards redder regions of the spectrum. To understand this gravitational redshift, think of a baseball hit high into the air, slowing as it climbs. Einstein's theory says that as a photon fights its way out of a gravitational field, it loses energy and its color reddens. Gravitational redshifts have been observed in diverse settings.
Earthbound Redshift
In 1960, Robert V. Pound and Glen A. Rebka demonstrated that a beam of very high energy gamma rays was ever so slightly redshifted as it climbed out of Earth's gravity and up an elevator shaft in the Jefferson Tower physics building at Harvard University. The redshift predicted by Einstein's Field Equations for the 74 ft. tall tower was but two parts in a thousand trillion. The gravitational redshift detected came within ten percent of the computed value. Quite a feat!

See also:
http://en.wikipedia.org/wiki/Pound%E2%80%93Rebka_experiment
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html
http://web.archive.org/web/20070630144936/http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html
http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/photon_mass.html
 

Offline Pmb

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Re: How much do all of the electrons on Earth weigh?
« Reply #16 on: 21/08/2009 20:41:56 »
Yea, if you use E=mc² on a photon with mass 0, you'll get E=0...
The relationship between a particle's proper energy E_0 and its proper mass m is E_0 = mc^2. The relationship between a particle's total inertial energy E and its inertial mass M (aka mas/relativistic mass) is E = Mc^2.
 

Offline labview1958

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Re: How much do all of the electrons on Earth weigh?
« Reply #17 on: 22/08/2009 07:04:48 »
My hunch is that the "mass" of the photon increases thus causing the space in the glass to bend. Thus the light wave bends in the glass and goes back to its original path when it is out of glass.
 

Offline lightarrow

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Re: How much do all of the electrons on Earth weigh?
« Reply #18 on: 22/08/2009 07:44:44 »
My hunch is that the "mass" of the photon increases thus causing the space in the glass to bend. Thus the light wave bends in the glass and goes back to its original path when it is out of glass.
Einstein's equation of general relativity says that energy too bends spacetime, not mass only.
 

Offline Farsight

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Re: How much do all of the electrons on Earth weigh?
« Reply #19 on: 24/08/2009 08:37:56 »
I'm sorry, what you say is wrong. The frequency increases because the energy increases. c stays constant.
It isn't wrong, lightarrow. It's unfamiliar to you and it isn't what you've been taught, but it isn't wrong. We measure the speed of light using clocks calibrated by the motion of light, hence we always measure the same value locally. But Einstein talked about the variable speed of light. See his 1911 paper On the Influence of Gravitation on the Propagation of Light and note the c = c0(1 + Φ/c²). In your Baez link, look at the section on general relativity, and note this:

"Einstein went on to discover a more general theory of relativity which explained gravity in terms of curved spacetime, and he talked about the speed of light changing in this new theory.  In the 1920 book "Relativity: the special and general theory" he wrote: . . . 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 [. . .] 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.  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".

Einstein talked about the variable speed of light. He really did. It might come as a shock, but the modern interpretation contradicts Einstein. And as per the falling plate, conservation of energy tells you that the blueshifted photon doesn't gain any energy from either the earth or the gravitational field.   


 
 

Offline lightarrow

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Re: How much do all of the electrons on Earth weigh?
« Reply #20 on: 24/08/2009 13:08:24 »
I'm sorry, what you say is wrong. The frequency increases because the energy increases. c stays constant.
It isn't wrong, lightarrow. It's unfamiliar to you and it isn't what you've been taught, but it isn't wrong. We measure the speed of light using clocks calibrated by the motion of light, hence we always measure the same value locally. But Einstein talked about the variable speed of light. See his 1911 paper On the Influence of Gravitation on the Propagation of Light and note the c = c0(1 + Φ/c²). In your Baez link, look at the section on general relativity, and note this:

"Einstein went on to discover a more general theory of relativity which explained gravity in terms of curved spacetime, and he talked about the speed of light changing in this new theory.  In the 1920 book "Relativity: the special and general theory" he wrote: . . . 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 [. . .] 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.  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".

Einstein talked about the variable speed of light. He really did. It might come as a shock, but the modern interpretation contradicts Einstein. And as per the falling plate, conservation of energy tells you that the blueshifted photon doesn't gain any energy from either the earth or the gravitational field. 

In that link:
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html
you didn't quote all it's written:
Quote
General Relativity

Einstein went on to discover a more general theory of relativity which explained gravity in terms of curved spacetime, and he talked about the speed of light changing in this new theory.  In the 1920 book "Relativity: the special and general theory" he wrote: . . . 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 [. . .] 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.  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.

The problem here comes from the fact that speed is a coordinate-dependent quantity, and is therefore somewhat ambiguous.  To determine speed (distance moved/time taken) you must first choose some standards of distance and time, and different choices can give different answers.  This is already true in special relativity: if you measure the speed of light in an accelerating reference frame, the answer will, in general, differ from c.

In special relativity, the speed of light is constant when measured in any inertial frame.  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.

If general relativity is correct, then the constancy of the speed of light in inertial frames is a tautology from the geometry of spacetime.  The causal structure of the universe is determined by the geometry of "null vectors".  Travelling at the speed c means following world-lines tangent to these null vectors.  The use of c as a conversion between units of metres and seconds, as in the SI definition of the metre, is fully justified on theoretical grounds as well as practical terms, because c is not merely the speed of light, it is a fundamental feature of the geometry of spacetime.

Like special relativity, some of the predictions of general relativity have been confirmed in many different observations.  The book listed below by Clifford Will is an excellent reference for further details.

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.
« Last Edit: 24/08/2009 13:10:49 by lightarrow »
 

Offline PhysBang

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Re: How much do all of the electrons on Earth weigh?
« Reply #21 on: 24/08/2009 21:57:05 »
In that link:
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html
you didn't quote all it's written:
If you do any research into Mr. John Duffield, you will discover that cherry-picking quotations is one of his specialties. For example, he has been shown time and time again that the paper from which he has drawn that quotation from Einstein is one that Einstein superceded with better work within 5 years of the publication of that paper. So even though he knows that choosing that quotation is a bad example for his argument from authority using Einstein, he does it anyway.
 

Offline Nizzle

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Re: How much do all of the electrons on Earth weigh?
« Reply #22 on: 25/08/2009 06:00:53 »
The use of c as a conversion between units of metres and seconds, as in the SI definition of the metre, is fully justified on theoretical grounds as well as practical terms, because c is not merely the speed of light, it is a fundamental feature of the geometry of spacetime.

I find all this very interesting.
Could someone explain how c is a fundamental feature of the geometry of spacetime please?
« Last Edit: 25/08/2009 06:02:55 by Nizzle »
 

Offline Farsight

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Re: How much do all of the electrons on Earth weigh?
« Reply #23 on: 25/08/2009 12:34:17 »
In that link: http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html you didn't quote all it's written:
I was going easy on the author. Look at the two important sections again:
 
"Einstein went on to discover a more general theory of relativity which explained gravity in terms of curved spacetime, and he talked about the speed of light changing in this new theory.  In the 1920 book "Relativity: the special and general theory" he wrote: . . . 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 [. . .] 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.  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".
   
"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".


On the one hand the article says the interpretation is perfectly valid and makes good physical sense, and later on it says it does not even make sense. It not only contradicts Einstein, it contradicts itself.

I'm not pulling the wool over your eyes with this. People like PhysBang defend the modern interpretation by directing ad-hominems at people like me without offering any evidence or logical argument, attempting to distract you from the very simple unassailable logic supported by the evidence that's there in the history and in the observation. The latter is "hidden in plain view". For example, imagine that I'm in a region of high gravitational potential holding a light clock in an orientation that avoids any issues of radial length contraction. PhysBang is holding an identical light clock in free space, and you're observing us both via telescopes and a TV monitor that puts both light clocks up on a split screen. What you see, is that my light goes slower than his. You attribute this to time dilation, but that's back to front, because the motion of light defines our standards of time and distance:

Under the International System of Units, the second is currently defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom....

The metre is the length of the path travelled by light in vacuum during a time interval of 1/299792458 of a second...

   
I experience gravitational time dilation because the light moves at a reduced rate where I am, not the other way around. I still measure the speed of light to be 299,792,458 m/s, as does PhysBang, but my seconds are different to his, and as you can see on your split-screen monitor, the two speeds are not the same. This really is Einstein's view. As an aside, the Baez article mentions Clifford M Will, who wrote this interesting paper: ttp://relativity.livingreviews.org/Articles/lrr-2006-3/. See section 2.1.2 where it says:

"Although special relativity itself never benefited from the kind of “crucial” experiments, such as the perihelion advance of Mercury and the deflection of light, that contributed so much to the initial acceptance of GR and to the fame of Einstein, the steady accumulation of experimental support, together with the successful merger of special relativity with quantum mechanics, led to its being accepted by mainstream physicists by the late 1920s, ultimately to become part of the standard toolkit of every working physicist".

Relativity was not completely accepted by mainstream physicists until the late 20s. However even this is debated by some, see http://en.wikipedia.org/wiki/Golden_age_of_general_relativity which says:

"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".  

What people are generally taught about relativity, is not quite how it is. Please note that I'm a strong supporter of relativity and Einstein, along with empirical evidence and experiment. Some people are not. 
 

Offline Farsight

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Re: How much do all of the electrons on Earth weigh?
« Reply #24 on: 25/08/2009 12:52:31 »
I find all this very interesting. Could someone explain how c is a fundamental feature of the geometry of spacetime please?
See above re the second and the metre. The speed of light is a conversion factor between our measures of distance and time. All motion is calibrated against the motion of light, hence c is a fundamental feature of the world in which we live.

Note however that Einstein's original General relativity talked about equations of motion, not curved spacetime. Whilst spacetime is the mathematical space used for calculations and useful predictions, what's actually out there isn't a block universe, or world lines or light cones. You can't actually see these things because they're mathematical entities with no objective existence of their own. What's out there is space and motion through it. Hence it's a little misleading to say c is a fundamental feature of spacetime geometry.
 

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Re: How much do all of the electrons on Earth weigh?
« Reply #24 on: 25/08/2009 12:52:31 »

 

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