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David Cooper:"As all frames are equally valid, every object will have a range of shapes..."...Will appear to have different shapes or will be different shapes? Do you understand the difference? That is the core of the argument.
Me:"Please don't automatically assume that I don’t understand SR and repeat that “all frames of reference yield equally valid measurements” as if that were an established fact."Did you even read that request? If so, did you understand its significance?
David:QuoteIt hasn't died, but you really need to stop slapping people across the face for attempting to answer your questions.I am radically honest. Look it up if you aren't familiar with the ‘radical’ part. No one yet has even attempted to answer the most fundamental key challenge illustrating how bogus length contraction is as applied to large objects. See #1 above and especially the final bolded note to you now edited in.
It hasn't died, but you really need to stop slapping people across the face for attempting to answer your questions.
You:QuoteI'll label these with LU for Lorentzian Universe and SR for Einstein's Special Relativity. So rather than addressing the issues I again presented above, you are again using this thread, as you did the one in Physics, to promote your own pet project.
I'll label these with LU for Lorentzian Universe and SR for Einstein's Special Relativity.
You:"SR: The Earth does not change shape."Agreed, but JP, a moderator with expertise in SR, though he will not admit it directly, argues that measurements are all we have for “reality,” so if we could measure earth from a near ‘c’ fly by frame it would BE very contracted in diameter, i.e., it would change shape.
You:"...part of its length is expressed in the time dimension of the frame in which it appears contracted." Nonsense. Time is only the concept required for all movement, not an entity. Solid objects do not shrink when observed from fast moving frames in which clocks slow down.
You:"SR: No force is applied."Of course not. And a “squished earth” would require a force of extreme magnitude for any change of shape, and even then it would be destroyed, not crushed into a severely oblate spheroid.
Regarding the probe capture challenge, you said:"...it's impossible to answer. If you slow the alien probe or speed up the shuttle so that they're going at the same speed as each other, clearly the probe won't fit."It is not impossible to answer. The answer is, “The probe won’t fit.” See again my point #4 bolded above for the significance of the answer.
It was obvious from the beginning that the shuttle must match the velocity of the probe to capture it, but I also made that explicit after all the collision speculation and proposed open doors for the probe to fly through the bay... nonsense.
You:QuoteSR: The muon finds a shorter physical path through the atmosphere which is not available to slower moving things. These shorter paths are always there, but only open to things that move fast....SR: As in the case of the muon, a shorter path (length) is available, as is a shortcut into the future.Nonsense! Like the overall shape of earth does not change, neither does the thickness/depth of its atmosphere. The fact that faster moving muons “live longer” (degrade more slowly) than expected of slower ones means that they travel further than expected in the ‘lifespan' of a lab muon. That allows them to reach earth’s surface. The atmosphere does not contract to accommodate them. The simpler explanation, here again, is the correct one. And there is no magically contracting atmosphere involved.
SR: The muon finds a shorter physical path through the atmosphere which is not available to slower moving things. These shorter paths are always there, but only open to things that move fast....SR: As in the case of the muon, a shorter path (length) is available, as is a shortcut into the future.
You: "... or find shorter paths into the future ..."Science fiction. There is no time travel. The present is the ongoing “now” always. The future is not yet present (here, now), and the past is not still present (here now.)
You:"As all frames are equally valid, every object will have a range of shapes..."Answered yesterday. You are simply parroting SR dogma.A “flattened earth” and a nearly spherical earth are not “equally valid.” Get over it.
You:"...on how the fabric of space is distorted in extra dimensions,..."What extra dimensions? Like the seven extra ones in the metaphysics (not physics) of M-theory?Space is 3-D volume, not a malleable entity/medium. Likewise time... that which elapses as things move. Put them together and what do you have? The volume (space) in which all things exist and move ( requiring time.) Not “The fabric of spacetime.” (Another version of “The Emperor’s New Clothes.”)...Minkowski’s “glorious nonentity.” (Ref: title of a paper by Brown and Pooley, compiled in a volume by Deiks of papers presented at one of the conferences of the International Society for the Advanced Study of Spacetime.)
You actually asked a question which invited the answer yes for two reasons: firstly you failed to lock it down to a capture where the two craft were travelling at the same speed, and secondly you were inviting answers relating to whether length contraction could make the probe fit in the cargo bay, which is something that's only going to work while the probe is moving at high speed relative to the shuttle.
In a two dimensional universe, there's someone like you arguing that this universe is the shape it appears to be to him. He has no idea that it's actually wrapped up into a tube, but he thinks he's right because he can't see outside of his own world.
Quote“If you want an answer that doesn't comply with the rules of SR, you need to find another theory.”No, I don’t. The fact that Earth is nearly spherical is not a theory. The theory (any version) that it changes shape with how it is observed is, as I said, ‘bogus.’
“If you want an answer that doesn't comply with the rules of SR, you need to find another theory.”
“Have you found some way to account for the Michelson Morley experiment which doesn't involve length contraction?”Yes. The speed of light is constant even when seen from or projected from a moving frame of reference. I don’t know ‘why’ , but I have no argument against the evidence. Light is *very mysterious* that way. This well documented evidence, however, does not require that physical objects either shrink or move closer together in space. Observation does not re-create reality (The belief that it does is classical idealism). The cosmos is as it is, independent of how it is observed... unless one is an idealist who believes that nothing exists but what is observed, or that things do not have properties of their own, independent of how they are observed.
“A flattened Earth could happen without being destroyed as the distances between the atoms in the direction of travel would seem to be normal within its frame of reference, so it would hold together perfectly well through the normal application of forces between atoms.”You agreed that no force is applied in length contraction. Do you have an answer to what could make “a flattened Earth happen” without applying any force?
“You reject the only alternative that I know of too, so I don't know what you think you're left with."My answer to this yesterday referred to earth as an immutable (in this context) nearly spherical natural object which no theory can make flattened. But your comments referred to the probe example. Again, the probe won’t fit into a 10 meter bay because it is not 10 meters long, as measured from Earth, but rather actually, in reality, 20 meters (if it is approaching Earth at 86.6 % of ‘c’.) This was a “reality check” on its actual length vs its apparent (contracted) length. Do you get my point?
I’ll be the spokesman for what I not only intended to ask but did in fact ask... “Will it fit?”No. The bay was 10 meters. The probe’s *apparent length* was 10 meters ( as seen from earth) while its *actual length* was 20 meters (as seen "alongside" as I did specify.)
On your “finding shorter paths into the future”...“Again my answer was an SR reply. What you're describing is Lorentzian.”No. My answer is based on my interest in and study of the ontology of time over many years, not “Lorentzian.” The concept of time as an entity through which one can travel is pure science fiction with absolutely no scientific evidence to support it. “It” is always “now”... no escaping it, no matter how fast or to where you go.
A “block universe” with all the past and all the future somehow “present” is another concept to which “bogus” applies. Where are the dinosaurs today? How about that human colony on Mars. Do they exist? (That's present tense.) No.
Space is three dimensional. Count them: Length, width, and height. For “the universe” they have no limits... The universe has no “walls.” A line is one dimensional. Two dimensions describe a plane. Anything or anyone *on that plane* will be a three dimensional being. Did you ever study basic geometry?
A two-dimensional being would not be three-dimensional.
Of course a two-dimensional being might not be viable for a number of obvious reasons, but I was illustrating the point that the shape we see things doesn't tell us what their true shape is - our universe could be rolled up in a fourth dimension just as easily.
Again, the probe won’t fit into a 10 meter bay because it is not 10 meters long, as measured from Earth, but rather actually, in reality, 20 meters (if it is approaching Earth at 86.6 % of ‘c’.) This was a “reality check” on its actual length vs its apparent (contracted) length. Do you get my point?
Everyone here got that point from the start, but *you aren't then comparing a contracted object with an uncontracted one*, so it doesn't tell you whether length contraction is real or not.
A Lorentzian universe could still build a block universe, so it can't be ruled out completely - the dinosaurs would still be back there in time, but you aren't going to be able to travel back there as your journey back there would already have to be written in the past of the block and that would result in circular causality.
So how should science best examine and measure Earth for best accuracy? Flying by at relativistic speeds or at rest with Earth, in Earth's frame of reference?
The correct answer to this question will solve the whole debated dilemma
Me: Quote Again, the probe won’t fit into a 10 meter bay because it is not 10 meters long, as measured from Earth, but rather actually, in reality, 20 meters (if it is approaching Earth at 86.6 % of ‘c’.) This was a “reality check” on its actual length vs its apparent (contracted) length. Do you get my point?You (my bold):QuoteEveryone here got that point from the start, but *you aren't then comparing a contracted object with an uncontracted one*, so it doesn't tell you whether length contraction is real or not.You still didn’t get it. The whole point of the exercise was to compare the contracted version of the probe as seen from earth (10 meters) with the non-contracted actual, real probe as seen from its own frame (20 meters.) Maybe that is just too simple for you to wrap your complicated concepts about length contraction around. The “contracted probe” was not its actual length. That was the point.
Like the warning on convex mirrors (..."Objects may appear larger/ closer than they are"), new version: "Objects approaching at high speeds may appear much shorter than they are!" So don't sent out a shuttle with a 10 meter bay to retrieve a 20 meter probe!
You:“...only you don't do length contraction and I don't know if you're doing strange things to clocks to compensate,”...So you haven’t comprehended anything I’ve said in this thread or the other about clocks at higher velocity ‘ticking” slower* or muons at higher velocities degrading slower and therefore traveling further than expected... rather than Earth’s atmosphere contracting "for each muon.”
In the first case (*) ‘ship’s time, as recorded by its clock, shows less than 4.37 years elapsed on the way to Alpha Centauri, but meanwhile earth will have orbited the sun more than 4.37 times (as a reference to what ‘a year’ means.) Meanwhile, its slower clock does not make earth and AC move closer together, because the real universe including the distance between stars, is not a result of how it might look from relativistic speeds.
You:QuoteA Lorentzian universe could still build a block universe, so it can't be ruled out completely - the dinosaurs would still be back there in time, but you aren't going to be able to travel back there as your journey back there would already have to be written in the past of the block and that would result in circular causality.Again, ou confuse science and sci-fi. The dinosaurs are all dead, not “back there in time” still grazing and killing each other. You can’t “travel back there” because “there” is not a place in a “timescape” to which you can travel. Same for a possible future colony on Mars. you can’t “visit” a “time in the future” which has not yet happened.
Yours is a colossal confusion, not only about time but the real world of nearly spherical planets and stars and the distances between them as they were distributed by gravity when they were formed as near spheres.
I will not address yet again your long-winded essays on length contraction. Yes, light speed is constant, regardless of frame of reference from which it is either seen or projected. I said that already. I also said that there is no empirical, scientific evidence whatsoever to show that constant ‘c’ requires that or causes solid objects and the distances between them to contract.
As I said the nearly spherical earth is a fact, not a theory, and SR theory can not make it, or any other planet or star “flattened.”I am done belaboring this debate with you as one who believes in time travel and in malleable planets and stars which can be squished flat via “length contraction.”
So how should science best examine and measure Earth for best accuracy? Flying by at relativistic speeds or at rest with Earth, in Earth's frame of reference?The correct answer to this question will solve the whole debated dilemma.
It would, but you'd need to know things that we don't and probably never can know....We don't know the best way to measure it - it depends on which theory is correct, and we don't necessarily even have the right one in our list of available theories. If SR is correct, my take on it would be to say that measuring the Earth while stationary/moving with it will give you its real shape - from other frames you are not seeing it properly.”
You still didn’t get it. The whole point of the exercise was to compare the contracted version of the probe as seen from earth (10 meters) with the non-contracted, actual, real probe as seen from its own frame (20 meters.) (edit) ...The “contracted probe” was not its actual length. That was the point.
If it was genuinely contracted, then its contracted length was its actual length at that time. It is completely incorrect to remove the contraction, measure it and then declare that it can't really have been contracted because it's now 20m long.
"Objects approaching at high speeds may appear much shorter than they are!" So don't sent out a shuttle with a 10 meter bay to retrieve a 20 meter probe!
That's largely correct, but if you don't mind crushing it you can actually collect it in a 10m container in a Lorentzian universe with all the crushing happening after it's been captured because it really can fit for an instant while it's still moving fast.
And since relativistic speeds on large scale (see title) are still not possible, (for empirical evidence) all the shrunken bodies and distances will remain theory in denial of what physics already knows about planet and star formation and distribution in space.
Assuming that the probe (like the example using earth as a solid object) is a rigid metallic object, what force do you propose as applied to it to make it “genuinely contracted,” (to 10 meters) given that, as it was built, and as it is measured in its own frame, it is actually 20 meters long?Again, differences in how things are observed, yielding different measurements for the same thing do not make the things themselves change shape. Very basic. Real forces are required to make real solid/rigid objects change shape. Observation does not change that which is observed. Until you understand that, this conversation is useless.
You even turn around and contradict your “genuinely contracted” assertion as follows:Me:Quote "Objects approaching at high speeds may appear much shorter than they are!" So don't sent out a shuttle with a 10 meter bay to retrieve a 20 meter probe!You:QuoteThat's largely correct, but if you don't mind crushing it you can actually collect it in a 10m container in a Lorentzian universe with all the crushing happening after it's been captured because it really can fit for an instant while it's still moving fast....And I *do mind crushing it!* I set up the example. It’s my baby. The mission was to retrieve it, not to destroy it, as if changing frames of reference could apply such a crushing force. You are very confused, having already agreed that length contraction does not entail any such force. You continually contradict yourself.
You:“The key point is how much the clocks are slowed and how much the lengths are modified.”My key point is that the slowing down of clocks at high velocity does not make lengths change. Actual force is required to change the length/shape of physical things. Apparent change is not the same as actual physical change. This point is lost on you and all proponents of length contraction.It is hardly worth continuing such a discussion until my above points are finally addressed.
There is no point in repeating my comments on the great mystery of constant ‘c’ and the MM experiment. The paradoxical property of constant ‘c’ does not re-create all physical objects and the distances between them into malleable effects of variable observation/ measurement.
You:“On the length contraction thing, I have no difficulty with the idea of a planet or star being increasingly flattened at higher speeds, ...” (my bold)This is completely out of touch with the physics of “solid objects” and the forces required to actually “flatten”, say, planets and stars. Length contraction confuses appearances with the things and distances so appearing.
It all started with Einstein saying that there is no reality but what appears to the observer. Ever since then one must be labeled as ignorant/ confused or bite the bullet, bow to his Great and Infallible Genius and blindly accept that SR has totally redefined physics... that objects actually change as they are observed to change.
That makes idealism the ruling philosophy of science, and realists must suffer the resulting ridicule and confine their babble to the backwaters of science forums, like this.
"Realists look at the MM experiment and conclude that length contraction is real. At that point, they either shift into the SR or Lorentzian camp. Your answer to MM appears to be to ignore it and pretend it isn't there, but it most certainly is there and it shows you to be wrong. That's why your babble belongs in the backwaters of science forums.
Lets take this to the most basic level which no one can deny (well... almost no one.)I said:"The paradoxical property of constant ‘c’ does not re-create all physical objects and the distances between them into malleable effects of variable observation/ measurement.'You said;"There's nothing paradoxical about it."Do you agree that physical objects like Earth and spacecraft exist and have properties like shape and size independent of observation?
Same question in reverse: Do you think that Earth changes shape as a result of how it is observed?
If not, do you think that the craft can BE both 20 meters and 10 meters long or that the Earth can have both a nearly 8000 mile diameter and a 1000 mile diameter... in the direction of an observing high speed frame, of course?If so, do you experience cognitive dissonance as you claim both to be true?Do you deny that there is a real world independent of observation?
Quote"Realists look at the MM experiment and conclude that length contraction is real. At that point, they either shift into the SR or Lorentzian camp. Your answer to MM appears to be to ignore it and pretend it isn't there, but it most certainly is there and it shows you to be wrong. That's why your babble belongs in the backwaters of science forums.A realist will answer my first two questions above in agreement with the first and denying the second. A realist will not agree that differences in observation require differences in that which is observed. They must ask by what means is a planet is squished flat and a spacecraft built 20 meters long is contracted to 10 meters, for whatever brief time in a theorist's mind. For a realist things do not change with how they are observed. Do you get at least that much of the argument from realism? If not, this is a totally futile exercise in communication.
In a Lorentzian universe it may be 20m long at rest and 10m long while moving at 0.866c through the fabric of space. In SR it can arguably be 20m long in absolute terms (many people in the SR camp don't agree with that, but it's fully compatible with SR none the less) and effectively other lengths (including 10m) in other frames.
You:QuoteIn a Lorentzian universe it may be 20m long at rest and 10m long while moving at 0.866c through the fabric of space. In SR it can arguably be 20m long in absolute terms (many people in the SR camp don't agree with that, but it's fully compatible with SR none the less) and effectively other lengths (including 10m) in other frames.I suggest we speak our own minds and leave Lorentz out of it until we sort it out.If the probe doesn't actually change in length as a result of observation, then what Lorentz believed is moot. And "the fabric of space" is not an established entity. It may well be just 3-D volume with "stuff" in it moving around, which, of course "takes time." And "...effectively other lengths in other frames..." again asserts observation as the definition of what is real, ignoring that the probe was built and remains 20 meters long regardless of how it is observed.
You:"I consider the Lorentzian universe to be the real realism ..."In case you haven't noticed, this conflicts with your first two replies quoted above.
Me: " Do you agree that physical objects like Earth and spacecraft exist and have properties like shape and size independent of observation?'David:"I personally agree with that."
Me:"Same question in reverse: Do you think that Earth changes shape as a result of how it is observed?"You:"No."
I personally agree with that....I didn't say that their shape and size can't be changed by movement. If you change the speed of either object, it will have a new shape and size which is independent of observation.
"A near 'c' fly-by of Earth-and-Sun (edit: observing a shorter AU) would not change the AU from its average 93 million miles..." Do you agree?A near 'c' fly-by of Earth would not change its diameter from nearly 8000 miles to, say around 1000 miles in the direction of flight. Do you agree.(Obviously it does not have both diameters, so one must be correct and the other incorrect, right?)
A rigid metallic "probe" approaching Earth at 86.6% of 'c' and observed from Earth to be 10 meters long will not fit in a shuttle cargo bay 10 meters long sent to retrieve it, even for an instant. Do you agree (that its true and immutable length... short of being crushed... is 20 meters?)
Do you agree that real forces are required to make real objects change shape/ length and real distances between objects shrink, i.e., to make objects move closer together? (Length contraction posits no such force involved in objects changing shapes or lengths or to move stars closer together in space.)
The distance between the observer and the moving frame or body is of absolutely no consequence. For an observer on earth the diameter of earth does not ever change because the velocity of one relative to the other is zero. For the observer at the near c velocity, that observer is at relative rest and the earth is in relative motion at near c. Therefore, the diameter of the earth in the direction of motion and its distance to the sun (if the earth and the sun are not in motion relative to each other) is contracted judged by that observer who is at relative rest.
At the moment the probe enters the cargo bay the relative velocities of the two better be near zero, in which case neither is contracted relative to the other. So, if it fits when both are at relative rest, it fits.
Einstein said that the body itself does not contract (Lorentz thought it did) rather; the body is contracted as judged from relative rest.
It appears to me that “real” is an empty meaningless category (drawer) whose immense importance lies only in that I place certain things inside it and not certain others.
What's your 3D volume without a fabric to enforce distance and to restrict the speed of light to c? SR has a fabric of space called Spacetime, and the old theory before Lorentz and Einstein came up with theirs had a fabric of space too. Remove it at your peril....
My whole criticism of length contraction is that the objects and distances themselves do not change lengths and shapes as they might appear to do as seen from various frames. That is why I keep asking, for instance, how Earth, a solid object, is *supposed* to flatten out (as seen from a near 'c' fly-by) with no application of force to squeeze it out of spherical. I am fine with a theoretical *image of Earth* as a very oblate spheroid in the above case.show demanded that such a non-mainstream view belongs here in the obscure "backwaters" of the forum, not in the serious physics section.
If you are still with respect to Earth, every Earth's dimension has a value, in your frame of reference; if you are moving with resperct to Earth, those dimensions are different, as measured in that new frame of reference (because of #).In relativity you *cannot* say: "the lenght is 2 metres", you have to say: "the lenght is 2 metres as measured in this specific frame of reference".