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Feb2313 08:40 AM
ZapperZ

1 
37,478 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,214 
Hello guys , beside Einstein's General Theory of Relativity by hervik , is there any lecture or book about this case ?...

Nov1312 02:44 AM
thecoop

3 
923 
So Newton says that gravity is an attractive force and some people believe in gravitons to transmit that attractive...

Feb2113 02:04 PM
Nugatory

6 
923 
Hello. I've been out of college for 10+ years now, but have never lost the desire to learn more. So I've been trying...

Apr709 09:25 AM
Ich

1 
922 
Hi This is regarding the pinhole camera concept regarding apparent angular size.
If we take the simultaneity...

Sep409 02:15 AM
Austin0

2 
922 
with the action \int (k(R 2 \Lambda)+L_m) \sqrt{g} the Einstein equation is:
R_{uv}\frac{1}{2}R g_{uv} \Lambda...

Dec2710 05:30 AM
haushofer

1 
922 
Hey guys, I just had a quiz on relativistic energy and there was a question on there that I was sure I got right but...

Mar811 09:21 PM
PAllen

5 
922 
Two spaceships are traveling relative to earth (stationary). One spaceship is going to the right at 0.8c the other is...

May811 08:23 AM
Redbelly98

3 
922 
Hi,
I am wondering if the cosmological constant is a constant in the sense that it can only have one value, ie some...

Jun2311 07:01 AM
haushofer

5 
922 
In a slightly disturbing episode of futurama, Fry (the main character) goes back in time and through a series of...

Jul1711 07:33 AM
George Jones

5 
922 
2 electrons are travelling around a black hole, after some time they meet themselves exactly at the horizon of the...

Apr1906 02:48 PM
George Jones

2 
921 
hi.
1. Why does the sign of the metric have to be (+,,,) or (,+,+,+)?
meaning why does the sign in front of...

May2307 01:08 AM
smallphi

1 
921 
see the attchments
Referring to fig 1
We have a clock that is used to set the time on a second clock. At point A...

Apr308 05:09 PM
rab99

4 
921 
I have two questions here:
1. As photons have no mass, why does light have a limited speed?
2. When the special...

Apr3009 12:31 PM
jamesbuk

1 
921 
I apologize for the poorly worded title. Let me try to explain my question better.
A scientific theory must be...

Oct1909 09:06 PM
atyy

4 
921 
I saw today in Ohanian's book:
"It is convenient to separate particle energies into kinetic and rest mass energies:...

Jan2710 05:48 PM
DaleSpam

1 
921 
This is not a question about relativity per se, but relates to it sufficiently I hope. Standard values for many...

Nov1711 07:35 AM
mes314159

2 
921 
I am steadily working my way through D'Inverno and have reached Chapter 20. On page 272 there is a problem which goes...

Nov2212 12:35 PM
TerryW

3 
921 
The PauliLubanski spin 4vector for a particle in its rest frame is given by Sμ = (0, Sx, Sy, Sz). (Note this is the...

Dec2212 11:35 AM
pervect

11 
921 
Actually, this is one of the question I was wondering about.
If mathematics allows for wormholes (And there's really...

Sep2904 03:32 PM
pervect

7 
920 
This thread is slightly related to another question: http://www.physicsforums.com/showthread.php?t=109211
I was...

Feb406 07:30 PM
ZapperZ

1 
920 
this isnt a homework question, incidentally
All the foormulas for time dilation, relaitivsitc momentum, do they...

Feb1906 07:31 PM
gulsen

1 
920 
Is the relativistic mass the reason that objects with mass cannot reach the speed of light?
>> The book gave it as...

Jan409 02:20 PM
JesseM

1 
920 
An electromagnetic field, as a plane wave, has a known spacetime dependence:
E = E0cos(ωtkx).
In a transparent...

Sep2709 09:29 AM
Bob_for_short

5 
920 
Ok, I've looked a bit into your Posts. The problem is, I suck at math (i.e. differential geometry).
So please tell...

May1310 01:22 PM
Chris Hillman

31 
920 
Hello,
It's well known that the action for a relativistic point particle is:
S=m\int...

Nov2210 02:08 AM
raul.cuesta

2 
920 
Hi Guys and girls
First have very little knowledge of this stuff, but watched a tv program today that made my head...

Dec2010 02:54 PM
JesseM

3 
920 
I understand that General Relativity is built on the Equivalence Principle.
Apparently there is a approximation to...

Oct1411 11:08 AM
johne1618

0 
920 
We know that
1. Mass causes bend in spacetime and this is the how gravitation occurs.
2. The formula for...

Jan2012 10:55 AM
bcrowell

2 
920 
Hi, I have some trouble with Theorem 2.2.1 in Wald's GR book p.15.
He derived formula 2.2.5 by using 2.2.4. Here,...

Jun1412 04:32 AM
syhpehtam

1 
920 
Hello there! I have a more or less silly and possibly obvious question that's been bugging me a lot. Here's the...

Dec413 02:54 PM
George Jones

8 
920 
This maybe a simple question, but if Earth orbits the Sun due to the Sun's mass 'curving' spacetime, wouldn't we be...

May1613 05:43 AM
surprise

20 
919 
has there been done any experiments to find out how electricfieldlines are affected by gravity? What do theory tell us...

Jun705 02:20 AM
werty

0 
919 
(see attachment)

Mar2908 12:28 PM
lark

0 
919 
Consider a particle that moves with speed V in the positive direction of the OX axis of the inertial reference frame...

Jul2708 04:29 AM
bernhard.rothenstein

1 
919 
I am trying to get my head around some of the basics of relativity.
dt' = ydt
Where dt is the time between 2...

Mar1009 10:00 AM
Ich

1 
919 
Does anybody know where I can see the Penrose diagrams for COLLAPSING charged or rotating black holes? Those diagrams...

Sep1409 09:32 AM
Demystifier

0 
919 
Is it possible to calculate the speed at which a massive object warps the fabric of space? Does the mass of said...

May911 05:27 PM
DrGreg

3 
919 
If earth is here 0 and I go at 90% the speed of light in that direction <in my space ship and my friend is going...

Jan2712 01:01 AM
ghwellsjr

2 
919 
i dont know this question goes at the right place
but i would like to know why speed of light remains constant
...

Apr1512 08:44 PM
rbj

5 
919 
Hi,
I'm a EE PhD student working a little bit out of my area, and have just gotten stumped trying to figure out the...

May1912 03:26 PM
Qreeus

3 
919 