PeterDonis's latest activity
-
PeterDonis reacted to Ibix's post in the thread I Convention for writing $\binom{1}{1}$ tensors in matrix form? with
Like.
I would say, in short, tensors aren't matrices and don't follow the same rules. For example, ##g_{ab}x^ax^b## is a perfectly valid... -
PeterDonis reacted to RUTA's post in the thread A Understanding Barandes' microscopic theory of causality with Like.
From SEP on Many-Worlds (written by Vaidman):
-
PeterDonis replied to the thread A Understanding Barandes' microscopic theory of causality.By "local" here is meant "free of action-at-a-distance", which, if you unpack further based on what's said in section 9 of the paper...
-
PeterDonis reacted to gentzen's post in the thread A Understanding Barandes' microscopic theory of causality with Like.
Bell on Bell’s theorem: The changing face of nonlocality Harvey R Brown, Christopher G Timpson https://arxiv.org/abs/1501.03521 So here...
-
PeterDonis replied to the thread A Understanding Barandes' microscopic theory of causality.Can you give any specific references?
-
PeterDonis replied to the thread A three month long summer vacation from public school seems stupid.After moderator review, this thread has been closed.
-
PeterDonis replied to the thread A Understanding Barandes' microscopic theory of causality.Why will this be the case?
-
PeterDonis replied to the thread I Question about discussions around quantum interpretations.Thanks, these are helpful.
-
PeterDonis replied to the thread A Is the variation of the metric ##\delta g_{\mu\nu}## a tensor?.Yes, and this is the relativity forum, not one of the math forums, so physics sloppiness wins out here. :cool:
-
PeterDonis replied to the thread A Is the variation of the metric ##\delta g_{\mu\nu}## a tensor?.I think @JimWhoKnew was assuming the presence of a metric, which gives you a natural mapping between the different vector spaces that...
-
PeterDonis replied to the thread A Is the variation of the metric ##\delta g_{\mu\nu}## a tensor?.Only in the presence of a metric, so that you can use it to freely raise and lower indexes. Otherwise those are three different...
-
PeterDonis reacted to A. Neumaier's post in the thread A Understanding Barandes' microscopic theory of causality with Like.
Possibly of interest: Albert, David Z. (2025) NOTES ON JACOB BARANDES’ VERSION OF QUANTUM MECHANICS. - Preprint...
-
PeterDonis replied to the thread I Synchronizing clocks in an inertial frame if light is anisotropic.Terminology for things like this is problematic, because it invites confusion both ways. "KE relative to the detector" sounds like it's...
-
PeterDonis replied to the thread I An invariant while crossing the horizon.Yes. No. The value of the metric parameter ##m## at that event is an invariant. It doesn't depend on any "point of view". No, we...
-
PeterDonis replied to the thread I Synchronizing clocks in an inertial frame if light is anisotropic.I believe it depends on the Anderson parameter ##\kappa##, yes. If I've done the math right, a pair of Lorentz frame velocities ##v##...