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Feb2313 08:40 AM
ZapperZ

1 
37,359 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,124 
I know that magnetic force due to a current carrying wire on a test charge moving w.r.t the wire(along the wire), can...

Mar2612 05:20 PM
DaleSpam

156 
11,918 
I found a decent page explaining this but it's a little deep for my understanding.
I think I understand the basics...

Jan3009 10:44 PM
Austin0

155 
11,771 
People always say the Universe is 14 billions year old.
But what does that mean?
What is the time of the...

Jan2312 10:07 PM
DaleSpam

155 
12,969 
We consider an spacelike infinitesimal separation {ds}^{2}<0
ds=+ or ib
Now I integrate ds along some path...

Jan1011 11:57 PM
PAllen

154 
8,475 
I posted this thought experiment in a previous thread before 4 months or so, but I would like to reiterate it now:
A...

Jan3012 10:19 PM
JDoolin

154 
7,921 
The Abraham's photon moment p_A=hbar*w/n*c is not Lorentz covariant, but it has been confirmed by several experiments....

Nov2311 07:20 AM
Vanadium 50

153 
15,367 
I'm curious about how people here view Einstein's prescription for determining simultaneity in an inertial frame, and...

May2708 12:26 AM
Ken G

152 
16,279 
I recently came across a very cool book called Div, Grad, and Curl are Dead by Burke. This is apparently a bit of a...

Feb113 06:23 PM
atyy

151 
8,895 
When a source begins to emit light, what exactly is occurring to produce an instantaneous velocity of c? If we're...

Jul1111 04:24 PM
GrayGhost

150 
11,314 
Mod note: Posts split off from http://www.physicsforums.com/showthread.php?p=4468795
Hi, WN, might the OP be...

Aug1513 03:09 PM
PeterDonis

150 
3,300 
Good evening,
As an effort for trying to understand Lorentz transformations, I'm trying to use them to derive the...

Jun810 05:16 AM
AdVen

149 
11,323 
So I did a degree some time ago and after watching a programme on TV, I decided to revisit relativity and set myself...

Feb811 07:05 PM
DaleSpam

149 
12,519 
I'm a little confused about certain assumptions usually made in GR as to how rigorous they are mathematically...

Dec812 06:33 AM
TrickyDicky

149 
9,330 
Anything that has energy must have some form of mass. Photons have both energy and momentum (Just because we chose to...

Jan2510 08:51 AM
Frame Dragger

148 
8,942 
I know that this is a very basic question but what is the correct formula for time dilation?
In Wikipedia etc. I...

Nov1009 12:29 PM
Rasalhague

146 
13,936 
Does Acceleration affect Lorentz contraction?
Suppose their was a Circle spinning around its center then its outer...

Feb810 12:28 PM
heldervelez

145 
15,730 
According to Weyl's postulate timelike geodesics should be hypersurface orthogonal, this in itself seems to clash with...

Oct1911 03:58 PM
TrickyDicky

145 
9,163 
I have a thought experiment for anyone interested. All replies welcome:
Imagine if you will, a large spherical...

Jul1406 10:34 AM
coalquay404

144 
8,048 
The relativistic momentum formula is p = \frac{mv}{\sqrt{1v/c^{2}}}. Since photons are massless and travel the speed...

Jul1611 06:08 PM
bcrowell

143 
9,375 
A variant of the classic twin paradox.
There are three triplets, who have the boring names of Adam, Bob and...

Sep1913 09:24 AM
ghwellsjr

143 
15,846 
Reading "Exploring Black Holes" I find that a particle following a geodesic towards a black hole always reaches the...

Dec2809 06:37 AM
George Jones

142 
15,830 
Has anyone here read and understood this introduction to Thomas rotation/precession?
...

Aug2610 08:25 PM
yuiop

142 
11,803 
If it is impossible to distinguish rest from motion, how is it that one of the twins' clock is slower than the other...

Sep510 12:54 PM
JesseM

142 
8,885 
Is it true that in GR the gauge is described by Guv while the potential is the Christoffel symbols just like the gauge...

Feb2612 07:04 PM
DaleSpam

142 
9,184 
I am asking this question in order to clarify something which I thought I had understood.
First of all, let me say...

Jan3113 10:54 AM
PeterDonis

141 
7,358 
I understand the principle of equivalence (e.g. thoughtexperiments with lifts etc), but how come that from it one can...

Jan2911 06:17 AM
Mueiz

140 
9,517 
This comes from this thread http://www.physicsforums.com/showthread.php?t=647627&page=7 discussion in posts...

Dec212 05:36 AM
harrylin

140 
10,069 
I've been told that time slows down so much inside a black hole that an event horizon never actually comes into...

Apr1613 01:59 AM
PAllen

140 
6,860 
Hello!
Are the transformations such as time dilation, length contraction and relativistic mass just observed ones or...

Oct1313 01:54 PM
TrickyDicky

140 
6,459 
He everybody :)
I guess I am not the only one who cannot comprehend the idea that the light has same speed for all...

Sep1711 07:32 PM
ghwellsjr

139 
8,606 
In his paper, Chou et. al., 2010 has demonstrated that an atomic clock at the height of our head ticks faster than an...

Aug613 02:26 AM
harrylin

138 
4,890 
In another thread, it's considered a generally accepted fact that the WEP is not valid anymore the way it was...

May511 10:53 AM
TrickyDicky

137 
7,521 
Processes taking place near high gravitation or moving at near light speed are slowed. General relativity tells that...

May3113 01:53 AM
dayalanand roy

137 
9,269 
Can someone please clarify for me whether length contraction in special relativity is considered a physical effect (a...

Jun1613 09:32 AM
ghwellsjr

137 
5,364 
I'm kind of a noob who's posted a question or two here before to settle arguments and such. Please don't kill me if...

Apr710 09:27 PM
stevmg

135 
11,466 
Can someone help me with understanding and explaining the Special theory of relativity.
I know the basics (time...

Dec1612 07:29 PM
DaleSpam

135 
8,873 
Could there be an absolute 'state of reference' somewhere in the universe, perhaps at the location of the original...

Mar2214 05:56 AM
DaleSpam

135 
2,782 
When a frame is moving in relation to an observer in his rest frame at infinity, and the frame is in a gravitational...

Jun610 04:15 AM
ZapperZ

134 
9,442 
What do you think about this explanation of EMfields using SR?
1TKSfAkWWN0

Oct1613 01:12 PM
Strafespar

134 
5,019 
I'm sticking my neck out because I just worked this out and may regret this post later.
The spaceship paradox...

Apr1214 06:12 PM
Mentz114

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4,955 