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Time Dilation. The faster you travel the longer I have to wait for you to return?

by Semifaded
Tags: dilation, faster, return, time, travel
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bobc2
#73
Dec17-12, 04:29 PM
P: 848
Quote Quote by ghwellsjr View Post
Now I want to show three more IRF's...
ghwellsjr, I was immersed in preparing my last post for Semifaded and by the time I got it posted I had to bail out here for an appointment. I'm anxious to get back to it. At a glance it looks like you have done a very nice job of presenting the kinds of details that further enhance the time dilation picture for the twin paradox scenario. I'm sure Semifaded will gain more insight from it. Thanks.
Vandam
#74
Dec17-12, 05:33 PM
P: 126
Quote Quote by DaleSpam View Post
No, there are many other block-universe sympathizers on the forums, including myself.

The distinction that you and Vandam have is that you are the only members that don't seem to realize that it is just an untestable philosophical interpretation of SR and not an unavoidable scientific deduction. In your fervor to promote a philosophical viewpoint you step way beyond what is scientifically justifiable. Most of the opposition you face is opposition to you and Vandam's overreaching assertion of an untestable philosophy, rather than opposition to the block universe concept itself.
As far as I can remember -at least a general impression I got- you have problems with block universe because you refuse accepting there are events out there, ready to be observed. For you, only your own now event is 'real'. Period. No wonder any discussion about the meaning of a mathematical number becomes problematic and can be considered philosophy...
If you think there are no pace-like events out there, ready to be observed (Ghwellsjr also literally said he is not interesed in the origin of observations), then not only Block Universe, but also Special Realtivity has to move to philosophy! The whole lot. And we then have to discuss what you mean by 'observers' and 'observing'. And we will definitely have to look what space and time cooridinates stand for. Even throw in some semantics.
You probably are too much influenced by QM. Do you believe the moon is out there if you do not look at it? Be carefull not to slide into solipsism. Solipsism is methaphysics, not physics. This is a physics forum. Einstein believed in an observer independent world, so it's fair the work in that context.
I think it might me necessary to go through a discussion of relativity of simultaneity again. I will show you that if you believe in an observer independent world, SR automatically leads to block universe. I might start a new thread on that (but not before next year..).

In the sketches below I show two time coordinate charts of two relative moving space travelers. Lorentz Tranformations, gamma, etc will give you the numbers. But physics is more than mathematics. More than just charts with coordinates. I show you where the observations making up the charts come from: 3D world sections through 4D block spacetime.
DaleSpam
#75
Dec17-12, 06:19 PM
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Quote Quote by Vandam View Post
As far as I can remember -at least a general impression I got- you have problems with block universe
You recall incorrectly. I have no problems with the block universe interpretation. I only have problems with your presentations of it.

Quote Quote by Vandam View Post
Be carefull not to slide into solipsism. Solipsism is methaphysics, not physics.
Here is a good example. I have never posted anything remotely in support of solipsim, nor has anyone else that I noticed. I don't understand your weird penchant for labeling anyone who disagrees with you as a "solipsist".

Quote Quote by Vandam View Post
I will show you that if you believe in an observer independent world, SR automatically leads to block universe.
And this is simply false. LET is an alternative interpretation of SR with an observer independent world that is not the block universe.

They are both interpretations of SR meaning that they lead to the same experimental predictions in all cases and therefore cannot be distinguished experimentally.
bobc2
#76
Dec17-12, 07:48 PM
P: 848
Quote Quote by DaleSpam View Post
No, there are many other block-universe sympathizers on the forums, including myself.
Good point, DaleSpam. In my comments I should have made a distinction between those who are favorable to the block universe concept based on philosophical considerations vs. those who feel that block universe is directly implied as a requirement of special relativity. You are probably correct in recognizing Vandam and I as the only forum members who feel that block universe is a requirement of special relativity.

Quote Quote by DaleSpam View Post
The distinction that you and Vandam have is that you are the only members that don't seem to realize that it is just an untestable philosophical interpretation of SR and not an unavoidable scientific deduction. In your fervor to promote a philosophical viewpoint you step way beyond what is scientifically justifiable. Most of the opposition you face is opposition to you and Vandam's overreaching assertion of an untestable philosophy, rather than opposition to the block universe concept itself.
I understand the distinction you are recognizing. And certainly with a theory like special relativity there is potential for some to interpret special relativity under the influence of his philosophical bias rather than basing the interpretation on measured data.

But, I want to emphasize that Vandam and I feel this model is based correctly on physical measurements and theoretical predictions. I presented the theoretical motivation in my original post in this thread. No one has responded with a counter argument that would logically refute the logic I presented. Vandam and I have both presented examples of measurements that would validate the theory. We contend that is physics, not philosophy. However, some have drawn on their philosophical bias to refute the block universe.

I'm not suggesting you have based your analysis on philosophical bias, because you have pointed to LET as a theory that predicts the same outcome as Einstein's special relativity. Thus, one could not single out block universe as unique.

Nevertherless, here are a couple of points that influence me:

1) LET is a largely discarded (or at least, ignored) theory. Virtually all physicists doing work in relativity (especially the general case) do it in the context of a 4-dimensional geometry. Einstein acknowledged that without Minkowski's 4-dimensional concept he would have gotten nowhere with general relativity.

2) The Einstein-Minkowski picture of special relativity is foundational, whereas LET is ad hoc.

3) It has been pointed out (sorry I cannot give you a reference) that LET is manifestly incompatible with the experimental results of entanglement tests, whereas block universe can be analyzed as compatible with those results.

But, my main point here is that I maintain that the block universe is a concept which is an integral part of special relativity (not a separate theory), derived from the special theory of relativity and also supported by measurements. The philosophy of physics was a required course for our PhD curriculum. On the last day of the course our professor asserted that "...physics never has and never will contribute anything to the understanding of physical reality...." I've been leary of philosophers ever since.

So, you should not characterize my position as one based on philosophy.

I may be guilty of faulty logic in interpreting the theoretical and experimental results.
PeterDonis
#77
Dec17-12, 08:08 PM
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Quote Quote by bobc2 View Post
the block universe is a concept which is an integral part of special relativity (not a separate theory), derived from the special theory of relativity and also supported by measurements.
Just to add some more thoughts to the discussion:

(1) If by "the block universe is integral to SR" you just mean "SR uses 4-dimensional spacetime to construct models", then of course nobody can dispute that. The disagreement, to the extent there is one, is about claims like "SR uses 4-D spacetime, so the block universe is what reality is really like".

(2) SR, as a physical theory, is wrong. It uses flat spacetime, but we know that spacetime is curved if there is any stress-energy present, and we know there is stress-energy present in the real universe. So we can't use SR, by itself, to justify claims about "what reality is really like".

(3) GR, as a physical theory, allows spacetime to be curved, and it also uses 4-D spacetime, so if we are going to argue that 4-D spacetime is "what reality is really like", we would do better to base such arguments on GR, not SR.

(4) However, there are formulations of GR, such as the ADM formalism, that view a 4-D spacetime model as a model of a 3-space "evolving in time". So the "block universe" is not the only possible interpretation of GR either.

(5) More importantly, though, GR, as a physical theory, is also wrong, because it doesn't include quantum mechanics. So we can't use GR, by itself, to justify claims about "what reality is really like" either.

(6) When we include quantum mechanics, we don't have a good theory (yet) that includes gravity. However, we do know one thing: quantum mechanics introduces an element of uncertainty that is not present in classical GR. And a key feature of GR (or SR) that is necessary to any argument that the block universe is "what reality is really like" is determinism. So when we include quantum mechanics, we can no longer argue that GR (or SR) leads us to the "block universe".
bobc2
#78
Dec17-12, 09:18 PM
P: 848
Quote Quote by PeterDonis View Post
Just to add some more thoughts to the discussion:
Thanks for your very well reasoned response. I'll try to add in a couple of my points of view.

Quote Quote by PeterDonis View Post
(1) If by "the block universe is integral to SR" you just mean "SR uses 4-dimensional spacetime to construct models", then of course nobody can dispute that. The disagreement, to the extent there is one, is about claims like "SR uses 4-D spacetime, so the block universe is what reality is really like".
Then, in your mind what does the 4-dimensional space-time model represent?

Quote Quote by PeterDonis View Post
(2) SR, as a physical theory, is wrong. It uses flat spacetime, but we know that spacetime is curved if there is any stress-energy present, and we know there is stress-energy present in the real universe. So we can't use SR, by itself, to justify claims about "what reality is really like".
We are interested first in understanding physical reality locally. Then, of course it must continue to be a part of the more general model.

Quote Quote by PeterDonis View Post
(3) GR, as a physical theory, allows spacetime to be curved, and it also uses 4-D spacetime, so if we are going to argue that 4-D spacetime is "what reality is really like", we would do better to base such arguments on GR, not SR.
Of course. It's just more logical to develop the local concepts of physics, then generalize them for the curved 4-dimensional universe.

Quote Quote by PeterDonis View Post
(4) However, there are formulations of GR, such as the ADM formalism, that view a 4-D spacetime model as a model of a 3-space "evolving in time". So the "block universe" is not the only possible interpretation of GR either.
On the contrary I feel that the ADM formulation with the foliations maintains a picture of a block universe. There may be complications, mathematically and conceptually, with regard to foliating in particular ways to accomodate certain different world line paths through the curved universe. I don't think it is necessary to get side tracked with special issues like black holes. We are just recognizing a simple fundamental concept for which we may not have all of the details worked out.

Quote Quote by PeterDonis View Post
(5) More importantly, though, GR, as a physical theory, is also wrong, because it doesn't include quantum mechanics. So we can't use GR, by itself, to justify claims about "what reality is really like" either.
Block universe in the special or general form does not have to include the usual concept of causality as considered casually. Notice that with the block universe causality does not have the same physical meaning as it does in the time evolving 3-dimensional model. So, causality at the elementary particle level is not necessary for the physical description. This should be true with both block universe and QM. That's why the entanglement experimental results are consistent with the block universe model.

Quote Quote by PeterDonis View Post
(6) When we include quantum mechanics, we don't have a good theory (yet) that includes gravity. However, we do know one thing: quantum mechanics introduces an element of uncertainty that is not present in classical GR. And a key feature of GR (or SR) that is necessary to any argument that the block universe is "what reality is really like" is determinism. So when we include quantum mechanics, we can no longer argue that GR (or SR) leads us to the "block universe".
That is incorrect. That's one of the significant aspects of the block universe--it is not necessary to predict the future in every detail. And the future does not have to be determined in a way that includes both macro and micro properties of the universe. The universe is just all there--the arrangement of worldlines of particles did not depend on the evolving in time of the 3-dimensional worlds (various hyperplanes--or GR foliations) at the elementary particle level. However the block universe was created or put together (we avoid any discussion of that, avoiding obvious traps into philosophy and theology), the presense of forces and response to forces (causality) were built in as part of the design. It would not be necessary to enforce the macro patterns of worldlines all the way down to the elementary particle. But, the observation and operation of physical laws in the sense of an evolving 3-D world is an illusion. Although, a clever construction of the block universe could arrange the elementary particle worldlines so as to present an appearance of causality emerging from interactions at the micro level.
PeterDonis
#79
Dec17-12, 10:41 PM
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Quote Quote by bobc2 View Post
Then, in your mind what does the 4-dimensional space-time model represent?
A model, which works fine as an approximation in lots of situations.

Quote Quote by bobc2 View Post
We are interested first in understanding physical reality locally.
That's an assumption about what "physical reality" is like. What if the true "physical reality" is not local?

Quote Quote by bobc2 View Post
On the contrary I feel that the ADM formulation with the foliations maintains a picture of a block universe.
It depends on what you mean by "block universe". Once again, if all you mean by it is "we can use 4-D spacetime as a model", then of course the ADM formulation is consistent with that. But the ADM formulation does not claim that a 4-D spacetime that "exists all at once" is what reality "is really like".

Quote Quote by bobc2 View Post
Notice that with the block universe causality does not have the same physical meaning as it does in the time evolving 3-dimensional model.
Why not? Both models use the light cones to determine which events are causally connected and which are not. You're going to have to elaborate on what you think the "physical meaning" of causality is if you think it's something more than just the light cone structure.

Quote Quote by bobc2 View Post
So, causality at the elementary particle level is not necessary for the physical description.
Why not? I don't see this either.

Quote Quote by bobc2 View Post
That's one of the significant aspects of the block universe--it is not necessary to predict the future in every detail.
Huh? That's the whole *point* of the "block universe" as a claim about "reality" as opposed to just a model. It claims that the entire 4-D spacetime "exists all at once". That means a single self-consistent solution to whatever physical laws determine the 4-D spacetime structure is what "exists". If that doesn't include every detail, then it isn't a well-defined 4-D spacetime structure.

Quote Quote by bobc2 View Post
And the future does not have to be determined in a way that includes both macro and micro properties of the universe.
The word "future" doesn't have a well-defined meaning here. You should just say that the entire 4-D spacetime exists, period. But that 4-D spacetime has to include all "macro and micro properties"; otherwise what are you saying "exists"?

Quote Quote by bobc2 View Post
The universe is just all there--the arrangement of worldlines of particles did not depend on the evolving in time of the 3-dimensional worlds (various hyperplanes--or GR foliations) at the elementary particle level.
But it does depend on whatever physical laws determine the 4-D solution. In SR, that 4-D solution is flat Minkowski spacetime, period. In GR, the 4-D solution is determined by the Einstein Field Equation plus boundary conditions. The 4-D solution is "just all there" in the "block universe" view, but that doesn't mean it isn't determined by laws. The laws don't "act in time", but they still act.

Quote Quote by bobc2 View Post
However the block universe was created or put together (we avoid any discussion of that, avoiding obvious traps into philosophy and theology),
You're also ignoring physical laws. See above. Physical laws are not "traps into philosophy and theology". They're the only justification for adopting any kind of viewpoint like the "block universe" in the first place. SR and GR are physical laws.

Quote Quote by bobc2 View Post
the presense of forces and response to forces (causality) were built in as part of the design.
Sure, they're part of the laws; in this case, the laws that determine the stress-energy tensor, including whatever additional field equations (such as Maxwell's Equations) are needed to fully specify the 4-D solution for the stress-energy tensor.

Quote Quote by bobc2 View Post
It would not be necessary to enforce the macro patterns of worldlines all the way down to the elementary particle.
This makes no sense. If you don't do this, you don't have a 4-D solution, hence you don't have a "block universe". Particle worldlines are part of the solution.

Quote Quote by bobc2 View Post
But, the observation and operation of physical laws in the sense of an evolving 3-D world is an illusion.
On the "block universe" view, yes, you could say this; but it would be very misleading if it induced people to draw the additional conclusion that there are no physical laws operating at all. As I said above, that is not at all the case.

Quote Quote by bobc2 View Post
Although, a clever construction of the block universe could arrange the elementary particle worldlines so as to present an appearance of causality emerging from interactions at the micro level.
As I said above, the elementary particle worldlines *are* arranged; they are determined as part of the 4-D solution. You can't just arbitrarily specify them; they are determined by the physical laws.

Also, you're again misunderstanding what "causality" means. In the 4-D spacetime view, causality just means the 4-D spacetime, as a geometric object, has a light cone structure, which determines whether any given pair of events is causally connected or not. That's all part of the 4-D spacetime solution; if you don't have it, you don't have a "block universe".
bobc2
#80
Dec18-12, 05:36 AM
P: 848
Sorry to not respond to you, PeterDonis. I just spent considerable time responding to each point in your last post. However, the PF program timed out, and when I responded to the request to log back in I was shut out and all of my text was lost. But, I think we have both expressed our points of view pretty well.

At the end of my post I suggested we terminate our comments relative to block universe. Once you start getting into some of the implications of block universe it can get quite controversal and eventually get way too far out into the weeds. I'm not sure if it is a good idea to try again to respond to your post. If Semifaded and others here wish to see my response, I would be glad to oblige. But, I suspect there would be relief to see an end to this discussion.

You have presented an excellent summary of the main objections to be brought up against the block model (as well as some of ghwellsjr and DaleSpam's inputs). I think it is O.K. for us to agree to disagree on this subject.

Now, I still need to go back and look at ghwellsjr's latest nice graphs.
Vandam
#81
Dec18-12, 06:30 AM
P: 126
(Sorry, I'm a bit late with this post.)
I think what Bob tries to convey is that Block Universe not only embraces deterministic but also indeterministic processes.
If all of a sudden a particle pops up 'out of nothing', the mathematics can only give us probabilities. But the particle popping out of nothing is already part of 4D spacetime. Causality is not necessarily a feature of Block universe. I guess you can have a block universe with ONLY indeterministic processes, but that would be really a weird one. Actually there might indeed be or a lot weird block universe bubbles out there, but in those Block universes 'life' as we now it might not work. That's probably why we are stuck in our Block universe.
In a fully deterministic Block universe 'causality is nothing more than the glue that holds the events together. Causality is not the 'cause' of events to happen. In block universe causality is only a result of first seeing A, and then B. (I think it was David Hume 250 years ago that brought that up). I do not know why our block universe is what it is so that we in the successioj of 3D cuts perceive causality and physical lanws. That discussion would indeed be a philosophical or theological issue... at this stage: maybe in a hundred years physics will have an explanation (hopefully thanks to Bob's and my, and many other's perseverance).
The interesting thing in physics is that our block universe apparently does not contain only fully deterministic relations (on a very small scale i.e). That's a great interesting discovery if it turns out to be correct... But it does't refute Block universe. On the contrary: Bob and I think QM proves that block universe is correct. But whether QM is compatible with Block universe or not is way off topic here (actually I am not that much involved in QM, I prefer to leave that topic to Bob). But SR's relativity of simultaneity = block universe. That's a good start.
PeterDonis
#82
Dec18-12, 08:52 AM
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Quote Quote by Vandam View Post
If all of a sudden a particle pops up 'out of nothing', the mathematics can only give us probabilities. But the particle popping out of nothing is already part of 4D spacetime.
Which means that unless you *know* all the events at which particles "pop out of nothing", you don't have a well-defined 4D spacetime. From the 4D viewpoint, a particle "popping out of nothing" just means it has a worldline that doesn't extend all the way from minus infinity to plus infinity: instead it appears at some finite place. But in order to properly define a 4D spacetime, you have to define *all* the worldlines, including those that happen to start at a finite place (if there are any).

Quote Quote by Vandam View Post
Causality is not necessarily a feature of Block universe.
Sure it is; a worldline that happens to appear at a finite place still has to keep within the light cones along its entire length.

Quote Quote by Vandam View Post
In block universe causality is only a result of first seeing A, and then B. (I think it was David Hume 250 years ago that brought that up).
But first seeing A and then seeing B is still governed by laws. They may be probabilistic laws, but they're still laws. And the term "first" isn't really appropriate here, because the "block universe" viewpoint says that the entire 4D spacetime just exists, it doesn't evolve in time. So really "causality" in a block universe means that event A has a particular geometric relationship to event B. That's true: the 4D spacetime has a light cone structure even if some worldlines don't extend all the way from one boundary to the other. See above.

Quote Quote by Vandam View Post
The interesting thing in physics is that our block universe apparently does not contain only fully deterministic relations (on a very small scale i.e). That's a great interesting discovery if it turns out to be correct... But it does't refute Block universe.
Nor does it *prove* it. Just following this statement you switch your ground, from this...

Quote Quote by Vandam View Post
Bob and I think QM proves that block universe is correct.
...to this...

Quote Quote by Vandam View Post
But whether QM is compatible with Block universe or not
QM being compatible with the block universe is very different from QM proving that the block universe is correct. I'll agree, for purposes of argument here, that QM can be made compatible with a "block universe" interpretation (though there are still lots of issues with doing that), but that does not show that QM *requires* a block universe interpretation. This is the same argument we've had about your claim that relativity of simultaneity requires a block universe; it doesn't. It's compatible with a block universe, but it doesn't require it.

Quote Quote by Vandam View Post
But SR's relativity of simultaneity = block universe. That's a good start.
Not if nobody except bobc2 agrees with it.
DaleSpam
#83
Dec18-12, 02:17 PM
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Quote Quote by bobc2 View Post
Good point, DaleSpam. In my comments I should have made a distinction between those who are favorable to the block universe concept based on philosophical considerations vs. those who feel that block universe is directly implied as a requirement of special relativity. You are probably correct in recognizing Vandam and I as the only forum members who feel that block universe is a requirement of special relativity.
I suspect that many of the mainstream physicists you refered to earlier may also fall into the same camp.

Quote Quote by bobc2 View Post
Vandam and I have both presented examples of measurements that would validate the theory. We contend that is physics, not philosophy.
The problem is that those exact same measurements would also validate LET. They do not allow you to choose between the two on the basis of the proposed experiments. In fact, there is no possible experiment since both use the Lorentz transform for making all of their experimental predictions. Therefore the only possible criteria to choose one over the other is philosophical.

Quote Quote by bobc2 View Post
1) LET is a largely discarded (or at least, ignored) theory. Virtually all physicists doing work in relativity (especially the general case) do it in the context of a 4-dimensional geometry. Einstein acknowledged that without Minkowski's 4-dimensional concept he would have gotten nowhere with general relativity.
Agreed, but this is peer-pressure, not empirical evidence.

Quote Quote by bobc2 View Post
2) The Einstein-Minkowski picture of special relativity is foundational, whereas LET is ad hoc.
Agreed, but this is philosophy, not evidence.

Quote Quote by bobc2 View Post
3) It has been pointed out (sorry I cannot give you a reference) that LET is manifestly incompatible with the experimental results of entanglement tests, whereas block universe can be analyzed as compatible with those results.
This is false. Any result which would invalidate LET would also invalidate the block universe since both make all of the same predictions.

Quote Quote by bobc2 View Post
The philosophy of physics was a required course for our PhD curriculum. On the last day of the course our professor asserted that "...physics never has and never will contribute anything to the understanding of physical reality...." I've been leary of philosophers ever since.

So, you should not characterize my position as one based on philosophy.
But your position is one based on philosophy, that is all that it possibly can be based on since it cannot be based on evidence.

If you prefer, you can say that it is based on aesthetics rather than philosophy. I am not sure there is any difference, but maybe "aesthetics" doesn't carry the negative connotation you have of "philosophy". I am certainly willing to use a different word if you feel that it would be less objectionable.
DaleSpam
#84
Dec18-12, 02:30 PM
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Quote Quote by Vandam View Post
Bob and I think QM proves that block universe is correct. ... But SR's relativity of simultaneity = block universe.
Both of these are false. Both QM and the relativity of simultaneity are compatible with LET as well as the block universe.
Vandam
#85
Dec21-12, 04:00 AM
P: 126
Quote Quote by DaleSpam View Post
Both of these are false. Both QM and the relativity of simultaneity are compatible with LET as well as the block universe.
Please explain how relativity of simultaneity is compatible with LET.
That's a contradiction in terms.
Relativity of simultaneity is compatible with the Lorentz transformations. But not with LET. LET does not give a physical explanation of the LT (Lorentz admited this).
SR does. That's Einstein's contribution.
See also my post:
http://www.physicsforums.com/showpos...9&postcount=14
DaleSpam
#86
Dec21-12, 04:05 PM
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Quote Quote by Vandam View Post
Please explain how relativity of simultaneity is compatible with LET.
That's a contradiction in terms.
Relativity of simultaneity is compatible with the Lorentz transformations. But not with LET.
Nonsense, LET uses the Lorentz transformations for its predictions, so any feature of the LT is obviously compatible with LET. The relativity of simultaneity is an inherent part of the LT. In LET just as in SR different frames disagree about whether or not two events are simultaneous.
Vandam
#87
Dec21-12, 04:36 PM
P: 126
Quote Quote by DaleSpam View Post
Nonsense, LET uses the Lorentz transformations for its predictions, so any feature of the LT is obviously compatible with LET. The relativity of simultaneity is an inherent part of the LT. In LET just as in SR different frames disagree about whether or not two events are simultaneous.
Nonsense. You have to step away from the ether (LET) to make all the time coordinates physical. Lorentz never did this. And he admited this:
<<The chief cause of my failure was my clinging to the idea that the variable t only can be considered as the true time and that my local time t' must be regarded as no more than an auxiliary mathematical quantity. In Einstein's theory, on the contrary, t' plays the same part as t; if we want to describe phenomena in terms of x'; y'; z'; t' we must work with these variables exactly as we could do with x; y; z; t.>>
The LT only have a full physical meaning in SR, not LET.
DaleSpam
#88
Dec21-12, 05:27 PM
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Quote Quote by Vandam View Post
Nonsense. You have to step away from the ether (LET) to make all the time coordinates physical.
So what? The relativity of simultaneity doesn't require you to "make all the time coordinates physical", whatever that means. All it requires is that different frames disagree on which events are simultaneous, which they do in LET.
Vandam
#89
Dec22-12, 04:39 AM
P: 126
Quote Quote by DaleSpam View Post
So what? The relativity of simultaneity doesn't require you to "make all the time coordinates physical", whatever that means. All it requires is that different frames disagree on which events are simultaneous, which they do in LET.
That's mathematical mumbo jumbo with no physical sygnificance.
You are lucky Einstein does not read you.
DaleSpam
#90
Dec22-12, 06:20 AM
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Quote Quote by Vandam View Post
That's mathematical mumbo jumbo with no physical sygnificance.
I agree. And yet, there is no experimental evidence which can select the LET mumbo jumbo over the block universe mumbo jumbo.

Quote Quote by Vandam View Post
You are lucky Einstein does not read you.
As long as we are channleing Einstein and pretending to know what he would say, I think that he would strongly object to your idea that any coordinates are physical. Certainly by the time GR was well established it was understood that coordinates are not physical, they are just mathematical conveniences.


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