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Here's an ancient thread with more references https://www.physicsforums.com/threads/the-twin-paradox-revisited-a-local-case-study.51197/

The underlying manifold of special relativity is ##R^4##. Flatness is not enough.

Voice of Baceprot (V.O.B.) (2026) This Indonesian Metal Band Is Changing Everything Loud Society and Voice of Baceprot - more...

I didn’t catch that myself until I read her Wikipedia page. My subset comment was about the links to the two Wikipedia pages I posted.

Hah. I completely misunderstood that! Funny name though.

Some history behind the Perimeter Institute for Theoretical Physics in Waterloo, Ontario. (I visited PI when it was just the brownstone...

https://en.wikipedia.org/wiki/Carl_H._Brans...

Instead of initial and final, it might be better to use event-labels: at event A, at time ##t_A##, the position is ##x_A##, and the...

Did you mean non-inertial motion? So, with your ##a=9.8\rm\ m/s^2##, upward-increments along the Velocity-axis are associated with...

Here it is playing rock guitar. Much better than a keyboard with a pitch wheel.

From https://trautman.fuw.edu.pl/publications/scientific-articles.html 39. (with W. Kopczyński) Simple spinors and real structures, J...

https://en.wikipedia.org/wiki/Hot_for_Teacher (1984) https://en.wikipedia.org/wiki/Van_Halen (1984) Van Halen - Hot For Teacher (Castle...

Rush performs Finding My Way live | 2026 Juno Awards https://www.rush.com/tour/fifty-something/

A Celebration of C.N. Yang and His Impact on Stony Brook Wang Center Theater, Stony Brook University Thursday, March 12, 2026 1:00 PM...

There is a Levi-Civita tensor ( https://en.wikipedia.org/wiki/Levi-Civita_symbol#Example:_Minkowski_space ), which is the volume element...