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Feb2313 08:40 AM
ZapperZ

1 
41,462 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,081 
Well...i have found the laws and theories related to relativity quite disturbing...few laws like the newton's stating...

Oct311 01:05 PM
darkhorror

3 
1,384 
For a timelike interval between 2 events, it is impossible to find an inertial reference frame in which the events...

Oct311 12:57 PM
PAllen

5 
1,895 
My first question, so sorry if it's in the wrong forum.
I'm trying to understand the Newtonian weak field...

Oct311 12:26 PM
peter46464

5 
1,586 
I'm a lay person who is interested in developing a better understanding of science in general, as well as specific...

Oct311 02:09 AM
logics

65 
6,101 
The main, or one of the main, arguments I hear about neutrinos flying faster than light is that it would violate...

Oct211 09:13 PM
Saw

11 
3,059 
Hey, does anyone know where I can find the correct metric for a rotating disk? Is the article at this link correct? ...

Oct211 05:33 PM
Doc Al

11 
2,121 
Hi all,
I've been reading some general relativity in my spare time (using Hartle). I'm a bit confused about...

Oct211 11:52 AM
jfy4

7 
2,210 
I was reading "Reinventing Gravity  A Physicist Goes Beyond Einstein" by Mr. John Moffat, btw it's a really good book...

Oct211 08:39 AM
Naty1

8 
2,172 
Here is a simple one. An observer far away from a black hole emits a light pulse every second. A second observer has...

Oct211 02:17 AM
Passionflower

10 
1,729 
I am trying to formulate an integral representing Tau between two rvalues for radial motion in the Schwarzschild...

Oct111 04:03 PM
PAllen

3 
1,159 
So, energy equals mass times the speed of light squared.
Energy can determine speed, because the energy is...

Oct111 11:47 AM
WannabeNewton

1 
870 
Hi I'm new and an idiot so please don't burn me, I wouldn't have come to a specialist forum if I could have found the...

Oct111 06:34 AM
phinds

4 
2,232 
I am a beginner in this field. I have read Special theory of relativity by Einstein, but the one written for...

Sep3011 04:38 PM
DaleSpam

8 
1,796 
I was talking with my friend and the best answer i could come up with is "It does." But, i could not explain why....

Sep3011 11:50 AM
ThomasT

36 
5,413 
A blue guy and a red guy are moving at the same speed in opposite directions with respect to some rest system as...

Sep2911 07:36 PM
bobc2

17 
2,860 
Alright I've asked before but this is still bugging me.
given that the mass energy equation is this
...

Sep2911 02:13 PM
DrStupid

15 
2,575 
How do Maxwell's equations predict that the speed of light is constant? I found different answers and some people even...

Sep2911 11:21 AM
fizzle

11 
6,863 
Having trouble trying to wrap my mind around how two reference frames (both in motion) can observe a third reference...

Sep2911 10:20 AM
M. Bachmeier

0 
667 
For the universe to be totally flat, and not just asymptotically closer to being flat as the universe expands,...

Sep2911 08:44 AM
kmarinas86

8 
1,926 
if a rocketship in space is approaching the speed of light and its relative mass is increasing then i assume the fuel...

Sep2811 04:58 PM
?????

3 
2,871 
A formula I know for the number of functionally independent components of the curvature tensor is: (n^2)(n^2 1)/12....

Sep2811 03:03 PM
Ben Niehoff

78 
6,008 
i have read about Hawking's theory of BH radiation based on the idea of spontaneous particle pair creation at the EH...

Sep2811 02:55 PM
PeterDonis

1 
844 
Greetings,
I have been having trouble deriving the equation for the general Lorentz boost for velocity in an...

Sep2811 08:06 AM
3nTr0pY

10 
4,679 
I tried to search everywhere but couldn't find an answer, so here it goes.
In Newtonian mechanics, the...

Sep2711 10:27 PM
Passionflower

8 
2,996 
I've been looking into the history of the speed of light values and when the last accepted value was set at. This...

Sep2711 06:36 PM
Mordred

13 
1,991 
for an inverse square field the force is proportional to 1/r^2
obviously we integrate over distance to get energy ≡...

Sep2711 12:57 AM
Parlyne

10 
1,554 
I am currently trying to self learn general relativity. I understand you need knowledge of an action principle, but...

Sep2611 09:22 PM
PAllen

3 
1,150 
Firstly, hello. This is my first post at Physics Forums, and I want to thank everyone in advance for contributing...

Sep2611 03:17 PM
DaleSpam

3 
1,244 
Why does faster than light travel or propagation mean time travel backwards to violate causality?

Sep2611 02:58 PM
DrStupid

36 
7,010 
So there's something that has bothered me for quite some time.
I know the normal equations of time dilation and...

Sep2611 12:08 PM
spacelike

2 
813 
Suppose, in the first case, that an object (initially at rest in frame S) accelerates, for whatever reason upward,...

Sep2611 12:55 AM
sudhirking

4 
1,065 
MTW 25.29 v.s. 25.38 (first formula)
Yesterday I made a quick calculation for a radially free falling observer in a...

Sep2511 05:23 PM
pervect

14 
1,375 
Hi,
I wonder, if we have two spaceship and they are moving tovard each other at the same 0,9c speed. what is the...

Sep2511 04:52 PM
harrylin

4 
1,789 
...shouldn't it:
1. become asymptotic to c as you pump more energy into it?
1a. don't I need to a lot more energy...

Sep2511 01:11 PM
kmarinas86

3 
1,548 
I was reading on relativity and the speed of light being constant and I thought of a something that seems too...

Sep2511 01:09 PM
anarcher

25 
7,156 
If you have three observers A, B, and C, if A is running backwards in time according to B, and B is running backwards...

Sep2511 12:43 PM
kmarinas86

8 
1,143 
Greetings,
First of all I believe this is the right forum as it isn't necessarily homework but more of a discussion...

Sep2511 11:04 AM
Naty1

1 
2,408 
I was reading through my textbook and it said that the angle between the axes of two inertial frames, one stationary...

Sep2511 09:41 AM
Bill_K

2 
1,946 
Hello,
I just spent some time reading the recent OPERACNGS paper on apparently FTL neutrinos ...

Sep2511 05:24 AM
Ryan_m_b

2 
1,438 
I've been reading through a book on relativity and I came across this
\mathcal{E}=p . v  L
\mathcal{E} =\frac{m...

Sep2511 04:54 AM
genericusrnme

2 
873 