PeterDonis's latest activity
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PeterDonis replied to the thread I Question about discussions around quantum interpretations.You can--by creating an environment where the quantum states of the decay products are already occupied, or partially occupied. (And for... -
PeterDonis reacted to pervect's post in the thread I Symmetry of motion in the special theory of relativity with
Like.
So far, so good. You have described the symmetry principle of relativity well. And it is indeed puzzling how this is possible - at... -
PeterDonis replied to the thread I Hawking After 54 Years Confirmed: BH surfaces don't shrink.As you seem to realize now, it isn't. It's a mathematical theorem. The main thing to understand about it, as you saw from the paper, is...
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PeterDonis replied to the thread I Hawking After 54 Years Confirmed: BH surfaces don't shrink.What's the difference?
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PeterDonis replied to the thread I A sufficient condition for integrability of equation ##\nabla g=0##.Sorry, this is simply wrong. We can't have a useful discussion if you continue to make wrong claims after repeated corrections. Thread...
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PeterDonis replied to the thread I A sufficient condition for integrability of equation ##\nabla g=0##.The tetrad in that expression is not the holonomic frame ##\partial_\mu##. It's the expressions ##X_i = h^\mu_i \partial_\mu##. The...
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PeterDonis replied to the thread A Dirac's integral for the energy-momentum of the gravitational field.It isn't. I explained what is in my previous post. It's a pseudotensor, not a tensor (because ##t## is a pseudotensor, not a tensor)...
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PeterDonis replied to the thread I A sufficient condition for integrability of equation ##\nabla g=0##.Please give a reference for this claim. I have never said any such thing. All I have said is that the Levi-Civita connection has...
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PeterDonis reacted to gmax137's post in the thread Other Don’t have a high enough IQ for physics so I want to give up with Like.
I think everything in your post (after the first sentence) is incorrect. Here's what I know: Online IQ tests are meaningless Those...
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PeterDonis reacted to Nugatory's post in the thread B What qualities does time have other than linearity, motion, and speed? with Like.
There's no sensible answer to your question until you have defined what you mean by the word "time". This being a physics forum where we...
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PeterDonis replied to the thread A Dirac's integral for the energy-momentum of the gravitational field.I was just about to hit "Post reply" when I saw this. See below. This might be one of those cases where Dirac's habit of implicitly...
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PeterDonis replied to the thread A Dirac's integral for the energy-momentum of the gravitational field.That's certainly true of Dirac, not just here but in general. And reading the text following (31.4), his assumptions (a) and (b) do...
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PeterDonis replied to the thread A Dirac's integral for the energy-momentum of the gravitational field.Where does Dirac do that over a 4-D hypercylinder? Nowhere that I can see.
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PeterDonis replied to the thread A Dirac's integral for the energy-momentum of the gravitational field.(31.2) is not an integral. It's a differential equation.
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PeterDonis replied to the thread A Dirac's integral for the energy-momentum of the gravitational field.I know. Now please look at my post, where I asked about a specific statement you made about an integral over a 4-D hypercylinder. That's...