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Feb2313 08:40 AM
ZapperZ

1 
42,729 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,372 
There is a general lack of awarenes about the fact that Lorenzian interpretation (LI) and Einsteinin...

Apr408 09:16 AM
wisp

2 
1,665 
"Relativity Revisited"
Authors: Flora Lopis (MIT), Max Tegmark (MIT)
abstract:
Was Einstein wrong? This paper...

Apr408 08:48 AM
robphy

3 
1,442 
Hey folks,
I'm reading a paper by Sean Carroll (http://arxiv.org/PS_cache/arxiv/pdf/0802/0802.0521v1.pdf).
In...

Apr408 01:50 AM
robousy

0 
1,155 
First off I apologize for lengthiness, but I want to be thorough... please read the entire post
I was just...

Apr308 08:35 PM
JesseM

30 
9,939 
When a photon passes from a high gravity field to a low gravity field, it is redshifted. Therefore it has less energy....

Apr308 07:15 PM
MeJennifer

4 
1,554 
Hi all,
I have recently been listening to one of Professor Richard Wolfson's physics lectures, and a question has...

Apr308 06:59 PM
tinytim

10 
1,692 
1. Let S be a stationary xcoordinate system. Let S' be a stationary x'coordinate system. Let the x'axis of system...

Apr308 05:43 PM
arbol

10 
2,337 
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 
989 
It is known that spinor can be view as the square root of vector,then what is motivation leading to twistor?

Apr308 10:26 AM
navigator

0 
1,051 
Hi all,
1) it is known (Liouville) that volumes in phase space are conserved under time evolution. Is there any...

Apr308 07:15 AM
arnesmeets

0 
1,167 
The most general spherically symmetric metric can be written as:
ds^2 =  dt^2 + X^2(r,t) dr^2 + R^2(r,t) (d\theta...

Apr208 05:54 PM
smallphi

0 
1,947 
Have physicists ever consider traveling into the future in order to travel back to the past? I know it sounds crazy,...

Apr208 04:23 PM
DaveC426913

11 
3,923 
Or maybe it isn't and apologies in advance if this isn't the appropriate forum but I was wondering if it is possible...

Apr208 10:46 AM
DaveC426913

28 
3,352 
What role does the Lorentz Group play in the General Relativity ?

Apr208 10:40 AM
harryjoon

1 
1,346 
time dialation is a function of only velocity ie if you are travelling @ C in any direction time stops yes? Time...

Apr208 04:07 AM
Denton

3 
1,441 
Timegravity relativity is based on the fact that the anything that can effect the speed of light can also effect...

Apr208 03:02 AM
rab99

5 
1,139 
I know mass has been converted into energy in fission and fusion bombs. But the converse  i.e., converting energy...

Apr208 02:46 AM
Schrodinger's Dog

10 
6,830 
Two photons are traveling parallel to one another.
Can the photons orbit one another perpendicular to the direction...

Apr208 12:50 AM
dst

1 
1,328 
To me the easiest way to arrive at the Lorentz transformation is by rotation, using one dimension for space and the...

Apr108 09:45 PM
snoopies622

3 
990 
I am in the process of trying to learn about some of the details that support general relativity. Therefore, my...

Apr108 06:24 PM
mysearch

6 
1,216 
Theoretically, if an object were to have negative rest mass, would it travel faster than light?

Apr108 06:14 PM
Shooting Star

1 
730 
Hello all,
We know that (E,p) are the components of a four vector and it is called the fourmomentum.
Likewise...

Apr108 05:10 PM
genneth

2 
1,055 
Is there any theories or something of that sort, which allows negative mass? Hence, v > c rather than v < c. This...

Apr108 12:30 PM
SdogV

38 
4,700 
you are in a plane flying east with a head wind of 10 kph. The speed of the plane is measured by measuring the wind...

Apr108 08:02 AM
DaleSpam

13 
9,045 
Hypothetical scenario: A small black hole passes by a much larger black hole at a velocity large enough to avoid...

Apr108 05:49 AM
MeJennifer

1 
1,173 
Can anybody explain what exactly is meant by conical singularity in a spacetime? What are known examples of it? How is...

Apr108 02:47 AM
arroy_0205

0 
3,332 
If the universe is bounded then there will be an absolute frame of reference.
This could be found by summing all...

Apr108 12:13 AM
rab99

14 
2,140 
Is it ok for a spacetime describing the Universe to be nonmaximally extended?
An example of nonmaximally extended...

Mar3108 02:24 PM
smallphi

0 
860 
Does anyone have any good English langauge references (textbook references or journal articles) for linear Born rigid...

Mar3108 01:46 PM
Ich

2 
1,564 
Sorry to bring up again a question that I asked before but I am still confused about this.
In SR we have Lorentz...

Mar3108 07:36 AM
Ich

3 
2,140 
if 2 clocks are synchronised in a stationary frame of refernece and then that frame of ref is accelerated up to a...

Mar3108 02:59 AM
rab99

14 
2,084 
I believe most of my questions relate GR:
1.) I've heard of gravity likened to a bowling ball sitting on a spring...

Mar3008 05:04 PM
CJames

11 
1,612 
If a and b are fourvectors then are ka and a+b also fourvectors?
My question arises because of the...

Mar3008 01:37 PM
DaleSpam

12 
2,784 
I have a very basic question about Special Relativity. I am very limited on my knowledge of physics and math and even...

Mar3008 12:34 PM
robphy

5 
1,058 
form twin paradox, let say Jerry is the one go travel to outer space then back to earth and Tom is the one stay in...

Mar3008 08:08 AM
cristo

1 
1,078 
hi, everone im new here, here is my 1st question, hope anyone can help me.
As the relative law, speed of any object...

Mar3008 07:35 AM
Doc Al

1 
791 
what y'all think about that portuguese guy (joćo magueijo) and his colleagues who have proposed that the speed of...

Mar2908 02:58 PM
belliott4488

29 
5,320 
(see attachment)

Mar2908 12:28 PM
lark

0 
955 
Are there other observations for the bending of light apart from Eddington 1919...i want to know that whether bending...

Mar2908 11:19 AM
Alfi

7 
1,739 
Please refer to http://en.wikipedia.org/wiki/Ehrenfest_paradox for a description of this very interesting paradox.
...

Mar2908 08:45 AM
jtbell

2 
4,001 