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Feb2313 08:40 AM
ZapperZ

1 
42,798 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,434 
Hello,
I am reading a book about General relativity, i understand that energy of the EM tensor go in the stress...

Aug2414 12:35 PM
dextercioby

4 
342 
In order for the light to take the same amount of time for both paths in the interferometer, simple geometry implies...

Aug2414 07:55 AM
Nugatory

11 
527 
Equations of state for photon gas and relativistic electron gas
This entry develops equations of state that are...

Aug2314 11:28 PM
andrewkirk

0 
105 
Definition of LargeScale Isotropy and Homogeneity
This post is part of my attempt to develop a formal definition...

Aug2314 11:23 PM
andrewkirk

0 
76 
Corrections to Narlikar paper
The paper by Jayant N Narlikar ’Spectral shifts
in General Relativity’ in the...

Aug2314 11:04 PM
andrewkirk

0 
80 
Einstein tensor in the FLRW frame  Part 1 of 2
This note develops a formula for the ##G^{00}## component of the...

Aug2314 10:48 PM
andrewkirk

1 
92 
Consequences of Energy conservation in a FLRW spacetime
This entry uses the local energy conservation law to derive...

Aug2314 10:39 PM
andrewkirk

0 
79 
So I have been reading about the nature of gravity, and I have become a little confused as to how gravity is produced....

Aug2314 08:44 PM
DaleSpam

6 
401 
Hi all. As you may be aware, there are a handful of modern derivations of the Papapetrou equations i.e. the equations...

Aug2314 04:24 PM
samalkhaiat

3 
273 
I would appreciate it if some senior member would give me feedback about this result that I have been using in my...

Aug2214 09:30 AM
m4r35n357

3 
403 
I would like to think that I understand how 4velocity is defined in special relativity. It makes sense to me that one...

Aug2214 04:42 AM
stevendaryl

4 
291 
Hi,
On p.4 of "A First Course in General Relativity", Shutz says that we redefine the units of time so that the new...

Aug2214 01:55 AM
porcupine137

18 
550 
Hi guys, i've been thinking about this experiment for the last few hours and I have a few questions which I am deeply...

Aug2214 12:31 AM
Orodruin

9 
473 
What if Schwatzchild has made the same mistake as Newton?
( 1  2MG / c2 r ) dt
can be view as a binomial...

Aug2114 11:24 AM
PeterDonis

5 
353 
In this source explaining how to derive the Schwarzchild metric, the person came up with an ansatz and worked from...

Aug2114 08:31 AM
Nugatory

1 
208 
Does the following argument prove that any method of faster than light communication is impossible?
1. A...

Aug2114 01:53 AM
Mark_Laverty

74 
2,460 
Depending on where I go to get a good understanding of the Lorentz transformations, I run into two formulas for time...

Aug2114 12:22 AM
Nugatory

2 
268 
It is known that, by the expansion of the universe, galaxies that are roughly 4200 megaparsecs away travel away from...

Aug2014 05:12 PM
phinds

15 
867 
Question the thing in the region of space that cannot be seen from us because they recede faster than the speed of...

Aug1914 08:08 AM
phinds

2 
296 
I'm looking for proof that Wolfgang Rindler coined the term Event Horizon. I believe that it was Rindler because...

Aug1914 03:34 AM
PhysicistMike

3 
318 
First, here is my source: http://www.thescienceforum.com/physics/30059solvingeinsteinfieldequations.html
As...

Aug1814 10:40 PM
PeterDonis

5 
462 
From what I know, to get the reverse trace form of the Einstein field equations, you must multiply both sides by gab...

Aug1814 03:14 PM
pervect

3 
333 
Hello, i am new here.
I have been studying SR en GR for a while on a hobby level,
and i keep pondering on the...

Aug1814 12:50 PM
phinds

37 
1,054 
If time is being warped by gravity/accelerated motion, does that mean that our clocks are inevitably slowed down since...

Aug1814 12:04 PM
PeterDonis

7 
398 
Is space time like a bowling ball on a trampoline or does it surround all matter like water does a submerged object?

Aug1814 06:44 AM
tom.stoer

15 
585 
Has this idea been recognized outside Frankfurt?
http://arxiv.org/abs/0812.1738
Pseudocomplex General Relativity...

Aug1814 05:28 AM
MrR

1 
369 
After learning more about relativity, and the vast amount of knowledge that is on this forum, I would like to clear up...

Aug1714 08:28 PM
jbriggs444

2 
278 
A first stage of the determination.
We have a body of length L = AB, which moves along the xaxis with velocity v,...

Aug1714 07:37 PM
atto

31 
1,170 
Imagine a theoretical universe which contained only two photons with the same energy. Imagine that each photon began...

Aug1714 05:55 PM
Sting33

18 
881 
How is gravity created? If you have any theories or new facts discovered please share. If u have your own theory...

Aug1714 05:08 AM
Chronos

18 
868 
In General Relativity spacetime is described by a metric. The most common one is the Schwarzschild metric, valid at...

Aug1614 04:39 PM
rlshuler

3 
320 
I think this will be a quick question...
If the Schw's metric is a solution of the vacuum, then what does the mass...

Aug1614 02:35 PM
Nugatory

3 
370 
I was watching a Science Video explaining why Ligtht travels slower in a Transparent Medium than in a Vacuum.
I...

Aug1614 12:37 PM
ChrisVer

5 
405 
Here is a new video, addressing a common question on this forum:
jlTVIMOix3I
It's similar to that one, but has...

Aug1614 08:35 AM
Greg Bernhardt

1 
489 
They say there is no measurement if travelling in a ship at the speed of light you can do to tell whether you are...

Aug1514 09:48 PM
PeterDonis

76 
1,715 
Recently read about a release from 2006 about an electromagnetic superconductor that generated a small gravity field...

Aug1514 06:42 PM
Fival

2 
273 
How can we define SPACE TIME CURVATURE with respect to dark energy and dark matter ?

Aug1514 01:35 PM
timmdeeg

2 
352 
Hi everyone,
I have a few questions about relativity.
I've been reading about relativity and its effects and I...

Aug1514 01:23 PM
Barry911

11 
598 
i have a question, that nobody seems to be able to answer : is math actually suited for reality ? Basically the idea...

Aug1414 09:05 PM
phinds

5 
855 
I feel I understand relativistic velocity addition fairly well. However, the way I usually see it modeled is with two...

Aug1414 05:14 PM
DiracPool

6 
515 