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Feb2313 08:40 AM
ZapperZ

1 
42,795 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,434 
Okay, everyone, I know that this is sounds like a setup question. And that's because it is. But please humor me,...

May2704 11:51 AM
russ_watters

8 
1,046 
How can a smooth deformation of a Lorentzian manifold possibly create one or more singularities?

Feb107 08:53 PM
quantum123

2 
1,046 
Hi,
How would go about arguing that the StressEnergy tensor is actually a tensor based on how it must be linear in...

Oct2209 07:16 PM
Azrael84

2 
1,046 
The derivaton I have seen (for a Schwarschild black hole) is this
One imagines a mass m attached to a long (well...

May2710 01:37 AM
yuiop

2 
1,046 
When an object moves in curved spacetime, how does its angular momentum vector transform? My hunch is that the...

Oct1010 03:12 PM
pervect

2 
1,046 
I understand that energy depends on mass but why multiply it by C˛ and not some other constant ?
Several...

Jan2812 03:59 PM
Matterwave

1 
1,046 
I have recently began to read about special relativity. I think I've got a decent grasp of how it works, but I have...

Apr1012 10:47 PM
yuiop

7 
1,046 
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 
1,046 
How will light switched on from a spacecraft moving faster than c appear( hypothetical spacecraft) to a ground...

Jul312 12:46 PM
micromass

10 
1,046 
Studying the movement of a particle on bound orbits around a black hole I found a fact that seemed a little strange...

Jul1613 07:17 PM
pervect

11 
1,045 
Hi,
I hope asking in right forum.
I'm trying to understand proper time concept but I'm afraid couldn't...

May1713 08:25 PM
pervect

15 
1,045 
This may sound mind numbingly stupid to those who are seasoned in Physics, but how do we know that it is impossible to...

May1506 03:24 PM
SpaceTiger

4 
1,045 
The Schwarzschild Solution to Einstein's Field Equations for gravity are said to be exact when outside a spherically...

Sep1309 04:02 PM
atyy

4 
1,045 
In my cosmology lectures they say that a negative curvature gives an infinite space but I was thinking what about the...

Feb1910 07:06 AM
George Jones

3 
1,045 
As long as there is any energy/mass at all in our universe, time will always be in a "slowed" state. So, let's say we...

Feb2611 03:42 AM
John232

9 
1,045 
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 
1,045 
Where can I find a picture of the magnetic field lines produced by a charged particle moving near the speed of light? ...

Aug3113 07:41 PM
Albertgauss

6 
1,045 
Hello guys!
I've been trying to get some intuition for differential forms. I know the formal theory and I know how...

Jul214 09:26 AM
micromass

2 
1,045 
Perhaps it is a stupid question, but really confuses me.
In QFT, virtual particles can be produced from vacuum, say,...

Jun2705 02:58 PM
hellfire

1 
1,044 
My question is, which photon is the one that first hits the square in the following example
If I had a large...

Jan1110 07:35 PM
Zula110100100

5 
1,044 
Hi all.
Suppose we have two objects A and B, and suppose we tie a rope R to the objects with the rope R's two edges...

Jun1911 09:30 PM
DaveC426913

5 
1,044 
i constantly feel that newton was right in measuring the relative velocity.einstein makes use of light which has a...

Aug2211 02:32 AM
harrylin

2 
1,044 
i strongly suspect that there is mathematical constraint on space time whicg is differensiable function ofmetrics and...

Jun2804 08:06 AM
einstein_vishnu

0 
1,043 
Here's a scenario I thought of a few days ago. I know there must be an easy explanation, but it hasn't come to me ......

Nov2404 01:46 PM
PBRMEASAP

2 
1,043 
the starship enterprise wishes to fly to a distant galaxy 85 light years away. at what speed would it have to travel...

Jan2405 01:25 AM
hype_chicky

3 
1,043 
I'm starting to get (Already am) really annoyed at how it is impossible to find an answer to what gravity is. For...

May2013 10:40 AM
slibbfalusken

11 
1,043 
There are 2 people, who are twins. One was born on earth, and the other was born in space. Because earth orbits the...

Aug405 11:33 AM
professor

8 
1,043 
This extract is from Bridgman, A Sophisticate's Primer of Relativity. 1962 Page 28. Only the last couple of sentences...

Oct2409 12:00 PM
Cleonis

9 
1,043 
Say we have dust filled universe. At some instant of time this universe has a mass density rho, and it evolves with...

Dec2109 08:20 PM
George Jones

2 
1,043 
Question: As an object approaches C and its length contracts, does spacetime contract also, causing the a larger...

Mar3010 03:28 PM
brainstorm

5 
1,043 
Hello!
I'm trying to get my head around general relativity at the moment...(!), and there's one aspect of it that's...

Apr2411 08:56 PM
JesseM

6 
1,043 
I recently watched a documentary on Albert Einstein that said the inspiration (or epiphany I guess) for the slowing of...

Jul2712 11:15 PM
claytonh4

4 
1,043 
A thought occurred to me when reading the Encarta article on relativity:
Now, it occurs to me that the velocity...

May404 08:44 PM
turin

8 
1,042 
so according to relativity, gravity is rly curves in space time. I imagine this in a 2d context, with a 2d world...

May505 08:37 PM
michael879

14 
1,042 
In the 3+1 formulation of GR we have the following basic variables:
g_{ij} = \textrm{metric on a spatial surface}...

Nov2906 06:12 PM
shoehorn

0 
1,042 
Hey, I'm stuck on part of the calculation for the compton wavelength. Basically, my notes go:
Energy of Electron
...

Feb1410 03:53 PM
jtbell

8 
1,042 
Is there an easy way to see this? can it be see via the penrose diagram? does it have anything to do with how when a...

Apr312 10:26 PM
George Jones

2 
1,042 
Can anyone explain to me what is contravariant and covariant? I just know that they are tensors with specific...

Sep2005 12:24 AM
pervect

2 
1,041 
if a ship is going at half the speed of of light (just imagine okay) and there is a light in the center of the ship...

Nov805 10:05 PM
franznietzsche

7 
1,041 
Hi,
I'm not a physicist and my idea of relativity is limited by wiki... but I have one question...
If I sit with...

May212 01:09 PM
HallsofIvy

7 
1,041 