Dale's latest activity
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Dale replied to the thread Undergrad Does the Alcubierre drive shorten distances?.There isn’t any one “the time coordinate”. You can choose time coordinates pretty arbitrarily, both inside and outside. Whatever you... -
Dale replied to the thread Undergrad Does the Alcubierre drive shorten distances?.So then, since the peculiar velocity is always ##c## the length of the path is just ##c## times the time. So, if you use the time...
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Dale reacted to PeterDonis's post in the thread Undergrad Does the Alcubierre drive shorten distances? with
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What path in spacetime is this integral taken over? You've described this integral as giving a distance, which would imply that it's an... -
Dale replied to the thread Undergrad Does the Alcubierre drive shorten distances?.The problem is that the "length of the path" is ambiguous in a curved spacetime. Here is the main issue: When you talk about the...
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Dale replied to the thread Undergrad What physical quantity has dimension [ML⁻³T⁻²] in electromagnetism?.That is good, but you still have not said which equations you are using. The dimensionality of a quantity only has meaning once both the...
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Dale replied to the thread Undergrad Capacitor Voltages at t = 0: Zero or Split?.With ideal circuits the mass and momentum of the electrons is always assumed to be zero. The problem in the OP is about the ideal...
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Dale reacted to PAllen's post in the thread Graduate How valid is the Block Universe theory? with Like.
Again, you could, in principle, disprove determinism. But, as I have argues above, determinism and block universe are actually...
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Dale replied to the thread Undergrad What physical quantity has dimension [ML⁻³T⁻²] in electromagnetism?.There isn’t any particularly deep significance for the dimensions of a particular quantity outside of the formulas where it appears and...
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Dale reacted to Ibix's post in the thread Undergrad Special Relativity in a closed universe with Like.
It applies everywhere at all scales. There are just some consequences of the topology. The easiest way to understand it, IMO, is in a...
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Dale replied to the thread Undergrad Special Relativity in a closed universe.Yes. I already said why: The first postulate fails in such a universe. This is a much better question. We know why this scenario breaks...
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Dale replied to the thread High School Calculating an impossible reference frame as my own homework problem.So, if this is supposed to be standard special relativity then the size of the universe is infinite. So any fraction or multiple of...
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Dale replied to the thread Undergrad Special Relativity in a closed universe.In such a universe the first postulate does not hold. So you have to be careful with any "these frames contradict" type of reasoning...
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Dale reacted to DarkloidNeos's post in the thread Graduate How valid is the Block Universe theory? with Like.
This is true but I've also been on the other end of that scale with extreme doubt to the point I didn't trust anything I said or...
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Dale replied to the thread Graduate How valid is the Block Universe theory?.I wouldn’t say it was even a new interpretation so much as a new derivation. His main contribution was taking Lorentz aether theory...
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Dale replied to the thread Graduate How valid is the Block Universe theory?.Lorentz aether makes no distinct experimental predictions from special relativity. Therefore it is an interpretation, not a distinct...