How do we determine who is the "observer" when calculating time dilation?
9016
How can time dilation be symmetric?
77557
Observed and Observable
143235
Twin Paradox, calculating spacetime intervals from both perspectives
80645
Time for two relativistic objects to meet
126447
How does velocity cause time dilation?
35663
Is there a formula that gives the position of an object depending on the time, but which doesn't allow the object to surpass the speed of light?
106863
Special relativity and imaginary coefficient of the time coordinate
131267
How can other processes affect measurements made with `time`?
22436
How is a second measured? And why is it measured that way?
8475
How is the classical twin paradox resolved?
87367
What constitutes an observation/measurement in QM?
131705
Relativity Of Simultaneity Confusion
66972
Is there any way to measure the one-way speed of light?
20974
Time dilation clock experiment: what would happen if the clock were flipped 90 degrees?
153552
Relativistic mass as seen by different observers
108569
Time dilation - why the observers see each other the slow one but then one of them is older or younger?
47242
Time dilation due to change in speed