Falsifying a young Universe. (re: Supernova 1987A)

There's very simple evidence that time exists in the distant universe. If you look at distant stars, wait a while, then look at them again, they will have changed. Hence they change state, so time must pass for them in order for these changes to occur.

Stronger evidence is the fact that distant stars move along orbits and paths exactly as General Relativity states they would orbit.We already know that distant locations do not have time that exists "the same" and that distant locations have different units of time. This relativity of time is built into General Relativity, the modern theory of gravity, so it is not something ignored or not taken into account.Since the stars behave exactly as General Relativity predicts and since the background light of the universe, the CMB, is exactly the correct brightness and mix of wavelengths as predicted by General Relativity and since galaxies are moving away from each other at exactly the rate you would expect for the CMB we see (i.e. both predictions of General Relativity are behaving consistently) and since both those predictions predict a universe that is 13.7 billion years old, I think the most likely conclusion is that the universe is billions of years old.

Okay, let's try this another way.General Relativity does assume time exists, but doesn't assume it works the same everywhere. Just to clear that up.Secondly, you ask what is the relevance of the CMB? Well it is a prediction of General Relativity, as is the motions of galaxies and stars.Since all of these behave exactly as GR describes, this provides evidential support to General Relativity's assumption of the existence of time.Does this constitute absolute proof that time exists, no. However it is very strong experimental evidence. Just like I can't absolutely say that the chair I'm sitting on exists. However I think such total solipsism isn't really interesting and doesn't provide any insightThirdly, science does "know" what time is, whereby "know" I mean our understanding of time is confirmed by every observation of the universe that we have ever made. Do we absolutely know, no. However again, this kind of absolute knowledge doesn't exist for anything. It's universal applicability makes it universally worthless as an observation.If you can, could you point out a feature of your doubts about General Relativity that are substantially different from just saying "Just because I can see, smell, touch and taste that sandwich, how do you know it exists?"EDIT: A clearer question, why do you think time passes in the solar system, but doubt it for distant stars?Edited by Son Goku, : No reason given.Edited by Son Goku, : No reason given.

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That clears nothing up. You made a vague claim. So show us how relativity assumes time, but not 'the same everywhere'?

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This has no non-technical answer. Relativity describes time using a metric tensor that varies with location see:
Robert Wald, General Relativity, Chapter 1It's a fundamental part of the theory, so much so that it's in the name, e.g. RelativityThe reason I bring up General Relativity is that it is a theory claiming time exists everywhere that has evidential support.

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So you admit you don't know what time is after all. OK.

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No I don't admit that and you know it. I said we know what time is unless one adopts a ridiculous form of philosophical skepticism. We know what time is in the same sense that we know how a tree works.What is the fundamental difference for you between our knowledge of time at distant stars vs our knowledge of time on Earth? Why do you consider our evidence in the former case insufficient?If you could answer this it would help the discussion.Edited by Son Goku, : No reason given.Edited by Admin, : "later" => "former"

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Even a technical answer is basically belief based.

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I meant: "Sorry I can't give a nontechnical answer".

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In other words you do calculations as if all vectors in the universe had uniform time?

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No, the opposite. We do calculations where the vectors have non-uniform time (metric tensor varies with location).

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That says nothing!
How does a tree work? How does a tree on the edge of the universe work? Time is not a tree so what is the connection here?

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It's an analogy, i.e. our knowledge of how trees work and how the distant universe works operate on the same abstract principles, i.e. we use instruments to detect and learn about things we cannot directly perceive with our senses. So we need microscopes, e.t.c. (you can tell I'm not a biologist!!) to learn about the cellular workings of a tree, since we cannot experience them directly. Similarly we use telescopes to observe the distant universe since we cannot experience it directly.Unless you also doubt we know how a tree works. (And I'm assuming you don't actually want me to explain to you how a tree works).

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We live here, and have been here and in the solar system and almost beyond a little. (probes) We know time exists here, and we can experience it measure how it works and such. Not true of time in the distant universe. Obviously.

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How are the distant light waves received from probes any different from the distant light waves received from stars, why do you believe one and not the other?

For every unit of time the star experiences we experience: Where is the time we experience is the mass of the star, is our distance from it, is the speed of light and is Newton's Gravitational constant.This is the prediction of General Relativity, hence as you can see, relativity does not consider time to be the same everywhere. Yes, but why do you trust the light from the probe, but not the light from the distant stars?Edited by Son Goku, : qs quote boxesEdited by Son Goku, : ExpansionEdited by Son Goku, : Nicer formatting and correct formula!

That formula shows that Relativity does not assume time is the same everywhere, which you claimed was something not taken into account.
Measuring stellar masses is a separate issue.Regardless, can you answer why you trust light from our probes in space, but not the light from distant stars?

The formula could be nonsense, but that wasn't my point. My point was the Relativity does not assume time to be the same everywhere. You claimed it did.Once more, I am saying the theory does not make an assumption of uniform time. I was not commenting on whether it was correct. This was in response to: I have shown you this, whether the theory is right is a separate issue.

This is like a Pandora's box in terms of its implications.You will only trust that there is time somewhere else, if something from our planet has traveled out there?Why? Why is the light from those probes so trust worthy just because they were once here?To nail this down, do you think there is time on Titania, the moon of Uranus? (There is a reason I ask this specifically)Edited by Son Goku, : Clarification

"Could be nonsense" in the sense that whether it is or not is irrelevant to refuting your original comment.This is getting very exasperating, the formula is a prediction of Relativity with varying time, hence one can see that Relativity does not assume uniform time.
The formula may be incorrect, but it is a formula of Relativity.Let me try an analogy. If somebody claimed "Herodotus said Persia was nine times the size of Greece" and somebody else said "No, look at page eighty, he says it is five times the size of Greece", that would refute the first statement. However Herodotus's history might still be wrong.It's the same here, you said "Relativity says time is uniform". I've showed you that relativity doesn't say that. I'm not commenting on Relativity's correctness.

Why? The vast majority of bodies in the solar system have only been seen by probes, not directly visited, such as Titania.Why do you think time works the same way there?Same goes for parts of the ocean we've only imaged from a distance, but not visited, why do you assume time flows normally there?

I didn't try to tell you no time was involved, I said it is involved but it's not uniform.
The formula describes non-uniform time, not no time. I don't know why you think I was claiming there was no time. What textbooks of General Relativity have you read that describe it as using time as we normally know of it, no textbook of GR that I have read says this. The describe General Relativity as using a highly unusual non-uniform notion of time, not the human concept.Could you supply a reference showing that General Relativity uses time in the way you say?

Yes, but the probe itself only viewed Titania remotely using a telescope. Exactly how we view stars.What is the difference between the Voyager probe viewing Titania with a telescope and another man-made craft (Hubble) viewing stars through a telescope? Why do you believe one and doubt the other?

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In both cases nothing from Earth has been there. What is the actual basis of your doubt? What do you require to no longer doubt the existence of time at a location?Edited by Son Goku, : Expansion

Well you asked.Regardless why do you trust time has passed on bodies like Titania which probes have viewed through telescopes, but you don't trust it when another man-made object in space, Hubble, sees stars via a telescope?Edited by Son Goku, : FormattingEdited by Son Goku, : I can't spell

FantasticWhy do you trust time has passed on bodies like Titania which probes have viewed through telescopes, but you don't trust it when another man-made object in space, Hubble, sees stars via a telescope?