Lecture Notes on General Relativity · HackerPapers discussions

Lecture Notes on General Relativity — mentioned by mr_mitm

Mon, 13 Jan 2025 02:09:43 GMT

Oh please. Do you really think the people who won the nobel prize for this discovery have a grade school level understanding of speed? You seem to be talking about peculiar velocities, which are absolutely negligible on cosmological scales and only the velocity caused by the expansion of spacetime is relevant. What they really did was measure the distances and redshifts of dozens of supernovae and looked which energy contents of the universe could explain the observed relationship assuming that the Friedman-Lemaitre-Robertson-Walker metric accurately describes the universe. Turns out you need…

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Lecture Notes on General Relativity — mentioned by pdonis

Thu, 23 May 2024 19:51:53 GMT

> So you are saying, there is a semi-reversible process where energy and volume are correlated? My original objection was to you thinking of it as a "process", or at least a process involving energy and volume. It's a relationship between stress-energy and spacetime geometry. > Should there actually be some specific amount of energy in place in order this density-to-scale transmutation to happen? There is no such "transmutation". That's not what's going on. Your questions aren't answerable because they are based on false premises. At this point I've done my best to explain what is and isn't…

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Lecture Notes on General Relativity — mentioned by pdonis

Sun, 17 Dec 2023 01:42:14 GMT

> Black holes are ordinary objects, if they are anything at all. No, they aren't. Their spacetime geometries are very, very different from those of ordinary objects. > Take any normal object and give it the mass of a black hole There is no such thing as "the mass of a black hole". What distinguishes a black hole from other objects is not its mass, but its spacetime geometry. That's particularly true for the holes studied by this paper, which are far smaller than the ones we actually see with our astronomical observations. The rest of your post is simply wrong. A black hole is not made of…

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Lecture Notes on General Relativity — mentioned by pdonis

Wed, 16 Feb 2022 02:46:16 GMT

> I'm very sure that you are wrong here What actual textbooks on relativity have you studied? If you haven't studied any, I would strongly suggest doing so before being this confident about your beliefs about relativity. Many pop science sources (including, unfortunately, books by physicists who should know better but who can't help themselves when there are no other experts peer reviewing their work) will say the kinds of things you're saying about photons "not experiencing time", but you won't find a textbook or peer-reviewed paper that says them, because such misstatements are weeded out.…

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Lecture Notes on General Relativity — mentioned by ivan_ah

Tue, 09 May 2017 05:41:50 GMT

These are pretty good notes. Here is the PDF version: https://arxiv.org/abs/gr-qc/9712019

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Lecture Notes on General Relativity — HN submission

Tue, 09 May 2017 03:53:00 GMT

Lecture Notes on General Relativity (1997)

105 points; 17 discussion replies on HN. Paper and source history. A submission is not an endorsement.

Lecture Notes on General Relativity — mentioned by raattgift

Sat, 10 Dec 2016 18:03:05 GMT

It's hard to gauge (pardon the pun) where to start you based on that. I'll guess that you're keen on understanding the General Relativity part in detail. Carroll and ‘t Hooft have kindly put up lecture notes that might be a good starting place. Stefan Waner has made available good lecture notes on differential geometry in the GR context. https://arxiv.org/abs/gr-qc/9712019 [Carroll] http://www.staff.science.uu.nl/~hooft101/lectures/genrel_201... ['t Hooft] http://www.zweigmedia.com/diff_geom/tc.html [Waner] If you can wrap your head around those you could proceed to any of the standard grad…

Paper and discussion history. A mention is not an endorsement.