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

Dec3107 02:06 AM
jtbell

0 
42,107 
Before posting anything, please review the Physics Forums Global Guidelines.
If you are seeking help with a...

Feb2313 08:40 AM
ZapperZ

1 
42,457 
I am doing a research about the compact Milne Universe in two dimensions Using special relativity.
such that (t,θ)...

Aug2813 08:35 AM
hazha

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31 
Definition of LargeScale Isotropy and Homogeneity
This post is part of my attempt to develop a formal definition...

Aug2314 11:23 PM
andrewkirk

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64 
Consequences of Energy conservation in a FLRW spacetime
This entry uses the local energy conservation law to derive...

Aug2314 10:39 PM
andrewkirk

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70 
Corrections to Narlikar paper
The paper by Jayant N Narlikar ’Spectral shifts
in General Relativity’ in the...

Aug2314 11:04 PM
andrewkirk

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70 
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 
71 
Equations of state for photon gas and relativistic electron gas
This entry develops equations of state that are...

Aug2314 11:28 PM
andrewkirk

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80 
Draft re Ricci vs Riemann tensors
This one is really just the beginning of a musing. I can't even remember if I...

Aug2814 02:54 AM
Markus Hanke

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112 
I know that you're going to probably say that a frame of reference doesn't make sense for light, but I've uploaded a...

Feb513 09:38 PM
Drakkith

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115 
Due to the blogs being removed, I thought it might be worthwhile posting a few in the forums
From 'Exploring...

Y 06:59 AM
stevebd1

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139 
For another BRS thread, I looked up some information at http://www.genealogy.ams.org/ and was completely sidetracked...

Mar110 05:00 PM
Chris Hillman

2 
140 
Due to the blogs being removed, I thought it might be worthwhile posting a few in the forums
zQdIjwoiu4
Time...

Y 02:39 PM
PeterDonis

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141 
Although I can't nominate myself for a Nobel Prize, I was wondering I any distinguished scientist would oppose such a...

Feb1213 02:55 AM
kloptok

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154 
I was recently trying to test something out with the Riemann tensor. I used only 2 dimensions for simplicity sake. As...

Y 07:00 PM
Matterwave

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162 
I'll try rephrasing my question, as I do not wish to question the theory itself. Verily, verily, it would be...

Feb1613 04:19 PM
Didymus

4 
170 
hi, I need an explanatory difference between timelike and space like events . examples will do, i know the mathematics...

Aug2714 01:44 AM
Orodruin

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172 
This old blog entry is being reposted here for archival purposes
because the blog system is being removed.
...

Aug2814 12:14 PM
robphy

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176 
This expression:
\Gammaavc\Gammacab
Can someone please show me how to multiply the two Christoffel symbol...

Aug1414 12:45 PM
HallsofIvy

1 
184 
Hello,
I was wondering what the exact definition of conformal transformations is.
This is a question in the...

Aug2914 06:55 AM
haushofer

2 
195 
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

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196 
The subject of Birkhoff's theorem has come up in a number of PF threads, and in the course of researching it for one...

Aug2814 07:06 PM
PeterDonis

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200 
Hi,
How can null geodesics be defined?
Obviously the concept of paralleltransport, of the tangent to the...

Aug3014 11:27 AM
WannabeNewton

2 
206 
Dear all,
I was reading this...

Aug914 03:04 PM
dextercioby

2 
208 
As far as I have the knowledge of GTR that a mass bends the space time around it.But why does this bend occur?The...

Aug2614 09:03 AM
Simon Bridge

2 
210 
In the formula for Christoffel symbols:
\Gammamij= \frac{1}{2}gmkki/∂xj) + (∂gjk/∂xi)  (∂gij/∂xk)
you do sum...

Aug2514 11:35 PM
Matterwave

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212 
When you have a general coordinate chart on spacetime you have a lot of freedom to pick your coordinates, but you are...

Aug1214 07:03 PM
Fredrik

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217 
Hello,
I am trying to understand Kaluza Klein theory on the five dimensional unification. It was mentioned over...

Aug2714 05:47 AM
DaleSpam

1 
217 
when muons are created in the atmosphere and fall to earth the earth clock runs faster. Thus, the "slower" muon clock...

Aug414 10:08 PM
PAllen

2 
218 
Hello,
I noticed quite a few questions on the HafeleKeating experiment here, but I believe none that have my exact...

Aug2814 06:23 AM
A.T.

9 
221 
This may be a stupid question, but have the various gravitational wave observatories around the world been tested by...

Jul3114 03:42 PM
PeterDonis

2 
224 
I'm seeing examples where for the person in the train the offset of both lights at the end of the train are not seen...

Aug2714 04:59 AM
jebii

6 
225 
I was reading Isaac Asimov's introductory physics text "Understanding Physics". In the chapter on Relativity, he...

Y 09:20 PM
Matterwave

8 
225 
I am somewhat distracted so this post will not be what it should, given that GAP is one of my interests.
For those...

Mar1110 05:17 PM
Chris Hillman

1 
233 
Hi, I'm trying to understand why the metric I've seen for AdS space,...

Jan2414 11:38 AM
copernicus1

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235 
On the spacetime manifold in general relativity, one chooses a basis at a point and express it by the partial...

May1714 02:59 PM
Matterwave

2 
236 
Hello,
Some knows how to Bondi deduce his radiating line element? I read some papers and there isn't any hint about...

May414 07:21 PM
btphysics

2 
239 
This is about Hans Ohanian, "Einstein's E = mc2 mistakes," http://arxiv.org/abs/0805.1400 , a historical paper that...

Jan2314 06:03 PM
bcrowell

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247 
...
The other night my telescope buddy and I were discussing gravities vs time over a campfire and beverages.
I...

Aug2814 07:51 AM
ghwellsjr

6 
249 
would time dilation occur if for example, i was making a hydrogen atom spin with the center of spin the atom? would...

May1914 03:40 PM
mfb

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251 
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 
251 
In classical mechanics we talk about homogeneous and inhomogeneous gravitational fields.
Do we do this with...

Feb514 09:35 AM
DaleSpam

1 
252 