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Feb2313 08:40 AM
ZapperZ

1 
42,265 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,902 
Length contraction happens only in direction of motion. Never perpendicular to the motion.
My questions are
1) Why...

Oct1011 08:16 AM
phinds

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2,218 
The formula which accounts for the Doppler shift is derived from the invarainace of the phase of a plane wave. The...

Mar509 02:11 AM
bernhard.rothenstein

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Suppose we have two ships A and B in uniform motion according to each other(A claims B to in motion and B claims A to...

Jun2011 11:45 AM
DaleSpam

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2,218 
Hello Forum,
I have been reading a book, the Fabric of the Cosmos, by Brian Greene. It talks about Newton...

Jan2312 07:35 PM
nitsuj

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Hey! I'm trying to understand time dilation in terms of minkowski diagrams.
Below I've added a diagram showing the...

Jan1912 02:44 PM
bobc2

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Einstein's theory of relativity?
In Length contraction and Time dialation, the distance between the two frames is...

Oct1606 10:36 PM
bernhard.rothenstein

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Does " What you don't see with your eyes, don't invent with your mouth" does work in special relativity?:rofl:

Oct2310 05:13 PM
yuiop

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I thought I would post this question here rather than in the Classical Physics formum because I expect the GR experts...

May1810 09:21 AM
stevenb

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So as I learn general relativity I am finding that it does not appear to address gravity in any way. The entire...

Aug1310 12:13 PM
JesseM

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There has been a lot of noise on this forum lately about A. Mayer's socalled "Transverse Gravitational Redshift." It...

Jun1211 07:19 PM
pervect

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2,216 
I'm taking general relativity and I understand how things work mathematically, but I'm trying to find ways of...

Apr1712 08:47 PM
PAllen

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2,216 
As the title says, imagine two observers with clocks A and B in space which move at vrel relative to each other.
...

Oct1812 01:44 AM
Simon Bridge

20 
2,216 
Hello.
The Einstein has following definition (in my course):
Gμε = Rμε  1/2Rgμε.
But why don't we just:
...

Aug2113 06:51 PM
nix00

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An expanding universe is a solution to Einstein's equations.
So particles become farther apart with time.
I...

Jul1104 09:18 AM
Mike2

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If speed of light is the upper limit of speed in the universe, how about force? (please refer to example for the...

Sep2309 04:22 PM
Meir Achuz

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2,215 
In MisnerThorneWheeler Gravitation, Chapter 4, Page 92, Box 4.1, at section 4, there is a formula for the...

Oct2609 05:24 PM
gheremond

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I am curious if there has been any research in to the elasticity of spacetime in regards to mass. If we consider that...

Oct2811 10:46 PM
yoron

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I thought I read something that said is was only a close approximation. If you did the full treatment you had to make...

Nov1906 11:27 AM
tehno

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A common concept used in the explanation of the twin paradox is that upon acceleration, one twin sees the other twin's...

Sep1807 05:42 PM
Xori

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2,214 

Jan3110 11:37 AM
sylas

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2,214 
I just read a sentence in GRAVITATION by MTW (aka the "Princeton Phonebook") that made me realize a confusion wrt the...

Jun1910 11:27 AM
Altabeh

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2,214 
How is the earth on a geodesic? Forgive me if this is basic. I had associated the time dilation effect with...

Mar2306 03:59 PM
robphy

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I was just wondering since I discussed this with some people before, but exactly how likely is it that wormholes in...

Aug707 07:24 PM
Cusp

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2,212 
I have been mulling over the idea of the oftquoted 'prohibition' on particles travelling 'faster than light'. While...

Jul912 10:37 AM
Demystifier

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I've read in multiple locations that GR is necessary to properly explain a corotating perspective/observer of the...

Feb2006 08:44 PM
clj4

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In "Does the inertia of a body depend upon its energy content?," http://fourmilab.ch/etexts/einstein/E_mc2/www/ ,...

Jul2212 08:41 PM
Matterwave

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How fast does gravity travel, and how do we know this? I know it can't travel faster than light, but it seems it's...

Jun2611 03:08 PM
danR

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Hello, I was wondering how collisions would when both objects are travelling at c.
Imagine 2 cars driving towards...

Nov1311 04:59 PM
Drakkith

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I've been trying to figure this one out for a while, I could use a bit of help. I think I'm getting close.
If we...

Nov2204 08:36 AM
pmb_phy

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So if I'm a fast object moving in a sphere, in my frame of reference the sphere begins to contract along the direction...

Jan2510 10:21 AM
Demystifier

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I asked this in one of my previous topics, but I just cannot find where I asked it, so here I am asking it again.
...

Dec1410 11:37 PM
atyy

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Few questions:
When approaching c , why does time slow down? When travelling at c and time stops, how does light have...

Jul811 10:26 AM
ZealScience

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with the increase of a body's velocity to the speed of light (v>c) so does the body's mass increase m>infinity....

Dec1903 10:35 PM
marcus

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According to GR, how do changes in the mass of an energy density become reflected in its gravitational field?
Is...

Apr2608 12:37 PM
Haelfix

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what is the meaning of topological black holes?
thanks

Jul608 02:37 AM
supakorn

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The constancy of the speed of ligth is a result of the Maxwell's equations.
And the Lorentz transformation is an...

Nov706 02:27 AM
Ich

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At http://en.wikipedia.org/wiki/Spacetime#Historical_origin I read the following quote:
Wouldn't this imply that...

Apr1907 03:20 PM
MeJennifer

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Hi folks
Since we often speak of relativistic mass here, and many people here post the URL to the relativity FAQ on...

Jun2508 08:47 PM
pmb_phy

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The paradox was discussed already in length, but I would like to add a twist. I take for granted, that the thread...

Jul2109 02:07 AM
Ich

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I'm working my way through D'Inverno's Understanding GR and have reached Chapter 7 with no real problems. I'm stuck...

Jan1610 06:01 AM
TerryW

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