Sagittarius A-Star's latest activity

The explanation of aberration in the light-clock scenario does not only work with classical particles, but also with EM waves. The...

Do you mean the case ##v=0##? You get ##2\arccos{} 0= \pi##, but not ##2\pi##. It seems that you want to describe the headlight effect...

I think the train actually distorts in its original rest frame, rather than tilting. Although it's a funny kind of stress-free...

In the restframe of the train, the bridge-length maybe even smaller than the train-length due to length contraction, if the bridge moves...

The crater depth will not be different.

A change in kinetic energy is ##\int \vec F \cdot d\vec s##. A force to decelerate the moving body by mechanical contact is in the end...

I think this must be multiplied with ##m## to get the four-momentum.

This means for proper time squared: ##(d\tau)^2 = (dT + \kappa dX)^2 - dX^2 - dY^2 - dZ^2\ \ \ \ \ (1)## Multiplying equation ##(1)##...

But I think it is correct: The reason is, that the term ##m ({dx \over d\tau}, {dy \over d\tau}, {dz \over d\tau})## does not contain...

Conserved energy is the time-component of the 4-momentum ##p_\mu=m {dx_\mu \over d\tau}##. ##E = m {dt \over d\tau}##. The conserved...

Please see A. Einstein: "The Meaning of Relativity"/Lecture 2, equations (39) and (42)...

Einstein modified Newton's definition ##p_x=mv_x## to ##p_x=m {dx \over d\tau}##. This does not depend on the clock-synchronization...

As @PeterDonis said in #22, the OP calculated in the Born coordinates (see the "edit" note at the end of #20). I just "tidied up" the...

I'm not sure the OP is actually using the same Born coordinates for both observers. The calculation in post #7 looks like it's...

To my understanding this is valid for oberserver ##p_1##, but not for ##p_2## described in the same coordinates.