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Feb2313 08:40 AM
ZapperZ

1 
37,432 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,181 
I know that it is observed that galaxies and stars thousands and millions of light years away are expanding away from...

Nov2812 04:46 PM
PeterDonis

4 
921 
Dear all,
This is a continuation of my previous thread, but I figure it's cleaner to start afresh with this topic....

Apr713 10:45 AM
NanakiXIII

6 
921 
Hello friend,
Still Something in my mind is saying that Relativity of simultaneity is the reason for time dilation...

Apr613 09:29 AM
arildno

13 
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 
920 
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 
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 
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 
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 
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 
920 
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 
920 
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 
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 
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 
920 
In the Galilean formula u=u'+v, the velocities are bold so we know they're vectors, so for instance if u'=(a,b), and...

Nov113 08:00 AM
clem

7 
920 
Biking at near the speed of light
If a biker is going at 0.99c, an observer standing still would notice his...

Mar2414 07:48 PM
jartsa

38 
920 
Hi.
BHs receive gravity of other stars and then move. Does this mean that information of gravity of other stars go...

Sep1012 07:31 AM
sweet springs

8 
919 
This thread is slightly related to another question: http://www.physicsforums.com/showthread.php?t=109211
I was...

Feb406 07:30 PM
ZapperZ

1 
919 
(see attachment)

Mar2908 12:28 PM
lark

0 
919 
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 
919 
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 
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 
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 
919 
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 
919 
I understand that General Relativity is built on the Equivalence Principle.
Apparently there is a approximation to...

Oct1411 11:08 AM
johne1618

0 
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 
this isnt a homework question, incidentally
All the foormulas for time dilation, relaitivsitc momentum, do they...

Feb1906 07:31 PM
gulsen

1 
918 
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 
918 
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 
918 
what was the real motive of MM experiment
to measure the speed of light or to measure the orbital speed (or speed of...

Aug310 07:14 AM
abhiiitb

6 
918 
From wiki:
'A "red herring" is a debating tactic that seeks to divert an opponent. A digression can, similarly, be...

Sep2510 11:14 AM
ClamShell

3 
918 
Can somebody clarify how the formula for variation of the auxilliary worldsheet metric is obtained due to...

Sep2411 03:44 PM
Ben Niehoff

3 
918 
I was wondering if, immediately following the expansion of the universe there might have been objects of matter with...

May1611 07:59 AM
Naty1

4 
918 
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 
918 
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 
917 
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 
917 
Hi,
I was reading on special relativity and was trying to understand it. However, I am still not very sure about...

Apr1110 12:02 AM
Fredrik

3 
917 
Hi everyone,
I found a derivation for relativistic momentum on this page:...

Dec1111 06:29 PM
DaleSpam

1 
917 
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 
916 
Ok, so given two hypothetically identical systems (like two spaceships with identical mass, onboard matter, etc.) am I...

Jul2211 09:21 AM
atyy

3 
916 