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Feb2313 08:40 AM
ZapperZ

1 
42,388 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,035 
We are trying to find the relative velocity in a Lemaitre observer's frame, when said observer passes an observer...

Jan2214 05:06 AM
Mentz114

15 
599 
After learning about special relativity, and the behavior of light, I do not understand why light is not able to reach...

Jan2114 05:36 PM
stevmg

41 
1,772 
The full Lagrangian for electrodynamics ##\mathcal{L}## can be expressed as ##\mathcal{L}=\mathcal{L}_\textrm{field}+...

Jan2114 09:21 AM
dextercioby

2 
369 
I've written an opensource book on special relativity: http://www.lightandmatter.com/sr/ . It's a work in progress,...

Jan2014 09:35 PM
bcrowell

2 
375 
In the wikipedia page a distinction is made in the definition of the SR 4acceleration between the case with...

Jan2014 03:32 PM
TrickyDicky

4 
380 
I remember reading something, long ago, to the effect that any attempt at creating a CTC would be doomed by energy...

Jan2014 01:30 PM
PAllen

4 
356 
If you don't have any charges or currents, the electromagnetic Lagrangian becomes...

Jan2014 12:33 PM
BruceW

14 
528 
The Lagrangian for a point particle is just L=m\sqrt{1v^2}. If instead we had a continuous distribution of matter,...

Jan2014 11:16 AM
dextercioby

10 
498 
I am just wondering  is spacetime curvature in the presence of energymomentum ( i.e. in interior solutions to the...

Jan2014 08:26 AM
Markus Hanke

4 
318 
Two twins A and (evil) B. Twin A remains "stationary" while evil B goes at near light speed toandfro. Ignoring...

Jan2014 02:36 AM
tom.stoer

10 
480 
Is there any reason to think that that the speed of light could vary with time (taking t=0 at Big Bang), ie, could...

Jan1914 03:27 PM
stevmg

28 
1,505 
I want to ask General Relativity is a force or Its a theory which explains how to spacetime curve and spacetime...

Jan1914 02:37 PM
A.T.

1 
300 
Hi,
In his original paper, Schwarzschild set the "'equation of the determinant" to be: g=1. In other words, he...

Jan1914 02:09 PM
Rob Sfic

17 
820 
A satellite orbiting the globe at some 300 miles at 18000 mph. Does the clock on the GPS tick slower or faster than...

Jan1914 12:04 AM
stevmg

2 
293 
If I start with the standard FRW cosmology equations,
$${\eqalign{
3\dot a^2/a^2&=8\pi\rho3k/a^2\cr
3\ddot...

Jan1814 11:23 PM
stevmg

5 
452 
In the special relativity the conservation of energy and momentum is represented by the equation:...

Jan1814 07:02 PM
WannabeNewton

21 
841 
Hi All,
Long time no post! I've asked a highlyrelated question to the one I'm about to ask here, but there's a...

Jan1814 12:42 PM
phyti

34 
1,882 
Ok folks, I've taken a stab at the Latex thing (for the first time, so please bear with me).
I've mentioned before...

Jan1814 09:49 AM
grzz

3 
323 
If I start with the stressenergy tensor T^{\mu\nu} of the electromagnetic field and then apply energymomentum...

Jan1714 11:05 AM
WannabeNewton

5 
625 
According to Wikipedia,
This definition doesn't sit well with me. Flux is defined as the rate that something...

Jan1614 10:31 PM
pervect

10 
518 
Here is a excellent book on special relativity and world lines.
...

Jan1614 08:56 PM
arydberg

0 
336 
I would appreciate views on the following understanding of length and distance in SR, restricted here to inertial...

Jan1614 04:52 PM
PAllen

73 
2,827 
If gravitational waves cause fluctuations in space time, than could all gravitational waves, large or small all would...

Jan1614 03:32 PM
ilikescience94

0 
282 
So I've been reading Einstein's theory of relativity, and at one point when discussing the Lorentz equations' proof...

Jan1614 12:45 PM
DaleSpam

3 
322 
Does \eta^{\alpha \beta}=\eta_{\alpha \beta} in all coordinate systems or just inertial coordinate systems?

Jan1614 11:43 AM
dEdt

3 
342 
I want to know how force works in relatvistivc mechanics.I searched it and I know the formula but I didn't know how it...

Jan1614 12:34 AM
Agerhell

19 
1,062 
If the space around the earth is curved according to general theory of relativity no lateral force is required to put...

Jan1514 05:00 PM
A.T.

6 
368 
I never seen any intuitive interpretation of the LHS of the equations.
I realize the question is a tall order.
But i...

Jan1514 04:31 PM
DaleSpam

7 
475 
I'm trying to figure out if there is an deep or simple relationship between the following two facts.
(1) A stick,...

Jan1514 01:28 PM
bcrowell

6 
642 
Hi! How this paper relates to the equivalence principle?
http://arxiv.org/pdf/grqc/0701084.pdf
"in contrast to...

Jan1514 09:52 AM
.Scott

3 
456 
Broad title, but really a specific question that I thought should be straightforward, but got stuck.
Consider the...

Jan1514 09:47 AM
PAllen

2 
478 
I know E=mc2 essentially means energy = mass. One might think why not just say E = m?
But I also know that: Every...

Jan1514 02:38 AM
luna4579

10 
1,077 
The most famous time traveling paradox is the Grandfather Paradox, where the traveler goes back in time to kill his...

Jan1514 01:06 AM
Vanadium 50

4 
441 
If I had a spoked disc made of unobtainium that could be spun up to .9999c outer rim speed, what would it look like as...

Jan1414 07:50 PM
pervect

14 
697 
In a number of threads over the years the idea has been discussed that if odometers were as well defined as (and as...

Jan1414 04:07 PM
ghwellsjr

53 
2,184 
In general relativity, the source of the gravitational field is the "stressenergy tensor"
I know that thing is not...

Jan1414 12:31 PM
Naty1

28 
1,629 
If a spacecraft moving near the speed of light has a camera set up inside observing the people in the spacecraft, and...

Jan1414 09:41 AM
.Scott

2 
642 
Let us say that we have small object of mass ##m## at some location far away from the earth (with zero velocity...

Jan1314 10:47 AM
PAllen

7 
604 
Does anyone have any favorite applications of the acceleration fourvector?
More specifically, the WP article...

Jan1314 10:22 AM
George Jones

3 
626 
Gravitomagnetism is this thing
https://en.wikipedia.org/wiki/Gravitomagnetism
Like electromagnetism equations, but...

Jan1314 07:18 AM
DaleSpam

48 
2,059 