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Feb2313 08:40 AM
ZapperZ

1 
41,710 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,351 
i'm toying around with the schwarzschild metric using it to find distances from a star in sphereical coordinates.
...

Dec406 10:48 PM
Chris Hillman

15 
3,445 
according to the theory nothing is faster than light so if there were a rod very very long(eigth ligth min long) and...

Apr608 11:36 PM
korinteren

36 
3,445 
How would you go about teaching relativity to someone who refuses to take anything on faith or argument from...

Jan512 07:38 AM
DaleSpam

37 
3,445 
We covered SR last semester in Modern Physics I and also covered early Quantum Theory and started Modern Quantum...

Jun2110 10:25 AM
GRDixon

38 
3,443 
As it's known, one of the most fundamental aspects of relativity is that all motion is relative.
But when we apply...

Feb114 10:47 AM
ghwellsjr

52 
3,443 
Lorentz Transformation says
x'=\frac{xut}{\sqrt{1u^2/c^2}}
Does its derivative
...

Jun704 06:31 AM
hemmul

1 
3,442 
My limited understanding of relativity tells me that "gravitational forces" are really just due to the curvature of...

May806 03:51 AM
Ich

16 
3,442 
The Principle of Relativity, (PR) may be summarised as the doctrine of no preferred frames of reference. It not only...

Oct104 02:25 AM
Garth

12 
3,441 
I understand it is always possible to diagonalize a metric to the form
diag
at any given point in spacetime...

Nov2706 11:18 PM
Chris Hillman

4 
3,440 
HI,
According to GR, gravitation is simply the geometry bending. Does this also apply on Earth? We can stick on...

Jul410 08:34 AM
Austin0

42 
3,440 
To be more exact, does gravitation have a force similar to the other basic forces: electromagnetic, strong and weak...

Jul704 11:56 PM
yogi

10 
3,439 
Hello,
My name is Joe and I am a junior in high school. I am taking AP Calculus right now along with a basic physics...

Nov1507 04:16 PM
Daverz

18 
3,439 
Le K_0 and K_1 be two inertial frames moving relative to each other with velocity v,
from Lorentz transfromation we...

May710 07:35 PM
atyy

47 
3,438 
I found some interesting task about tachyons:
"Spaceship A sends to spaceship B ( distance between A and B is...

Oct1307 06:54 PM
einstein_fan

12 
3,436 
Some introductory texts and most "popular" literature has not kept up with modern conventions and mathematical...

Jan1104 10:33 PM
DW

30 
3,435 
I'm wrapping up 3 weeks on relativity in my freshman calcbased physics course at the community college where I teach....

Nov312 10:32 AM
zonde

31 
3,434 
I know that it took approximately 3 minutes for lights to travel from sun to earth. Let say the sun is gone now. Like...

Sep1507 03:01 PM
RandallB

21 
3,433 
There is some discussion about the expansion "of space" in a thread that actually belongs to a different topic so I...

Mar104 09:15 PM
yogi

27 
3,432 
Is it possible for anything in the universe to have absolute zero velocity? I'm not talking about Zero Velocity in...

Nov1111 08:36 PM
iox108

24 
3,432 
I read about Einstein's hole argument and about diffeomorphism. Pasive diffeomorphism is changing of coordinate...

Mar2512 01:02 PM
momchil

13 
3,432 
Restmass:
m_0 = \sqrt{\frac{E^2}{c^4}  \frac{p^2_x}{c^2}  \frac{p^2_y}{c^2}  \frac{p^2_z}{c^2}}
Relativistic...

Feb1010 12:48 AM
dimsun

22 
3,432 
I'm curious about something  What quantities in physics do you think are "defined" quantities, i.e. quantities which...

Dec604 07:14 PM
pervect

10 
3,431 
Hi,
I'm stuggeling trying to understand the physics behind this. I just don't know where to start. Everything I...

May1105 02:16 AM
JesseM

36 
3,428 
According to "physics today" ...

May1512 10:05 AM
Histspec

17 
3,428 
Hi all,
I have been interested in the Theory of Special Relativity for the past few years, and there is something...

Aug3110 05:38 PM
DaleSpam

6 
3,427 
Hey everyone, I've searched the threads for an answer to my question but came up short. Basically what I want to know...

Jun1012 06:11 PM
bobc2

21 
3,423 
Consider the clocks C(0)(x=0,y=0) ticking and clock C(x,y=0) stopped and fixed to read t=x/c. Source S(0,0) emits a...

Jul2107 02:50 PM
country boy

18 
3,421 
If we take a photon as our frame of reference is it safe to say that the universe moves relative to "Us" at the speed...

Aug2904 06:12 PM
Nenad

44 
3,420 
I have a problem with relitive motion. If a light source is moving toward me a some high percent of c, the light will...

Aug508 09:54 PM
JesseM

27 
3,420 
Hello all,
I am new to the Forum and have no formal Physics training. I have an interest in the subject mainly due...

Oct809 06:32 PM
DaveC426913

16 
3,420 
Sorry if this has been asked, but I did a search and didn't find a relating topic.
This thought came to me a few...

Oct2409 09:58 PM
pervect

45 
3,420 
I recently read somewhere that speed of light is faster in cesium vapors. It is described as leaving the cesium...

Aug2810 02:32 PM
bcrowell

5 
3,420 
I've heard that if the speed of light were to change there would be no effect on the universe because changing it...

Feb208 06:41 PM
rbj

22 
3,419 
http://www.simplegravity.com/images/MichelsonMorley.jpg
I think General Relativity would argue that the light...

Sep2209 09:34 AM
A.T.

6 
3,417 
Let me know if I've got this right. If there is no absolute rest and everything is relative then everything is moving...

Jan3110 05:56 AM
ZapperZ

20 
3,417 
Hello,
I don't understand what is the difference between. e.g. the (1,1)tensor T_{a}^{b} and T^{b}_{a}, i.e. when...

Feb309 09:20 AM
robphy

10 
3,414 
It is my understanding that the velocity of gravity is assumed to be that of electromagnetic velocity i.e. “c” in...

Jul508 09:52 AM
Alex_B

9 
3,413 
The cosmological redshift can be understood in terms of time dilation.
In an expanding Universe light travels on a...

Aug813 02:01 PM
Drakkith

45 
3,412 
I would appreciate if some learned folk could answer these questions to increase my understanding.
1. Does GR...

Nov907 12:32 AM
robphy

18 
3,411 
So I have been wondering about something, this is completely theoretical obviously you cannot sit on a photon but...

Jan211 05:13 PM
tunkcart

14 
3,411 