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Feb2313 08:40 AM
ZapperZ

1 
42,457 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,107 
I believe Einstein said,
1.There are four dimensions to space, the normal three plus time.
2. Speed of light...

Sep1405 01:04 PM
reilly

17 
3,507 
Hello, recently I saw a poster with a clip from a magazine that had this situation and I was wondering if this is a...

Oct2005 10:48 AM
jimmies

6 
3,506 
We have all seen the graphs of space time. The ones that look like a bowling ball pushed into a bed. But what are...

May610 02:49 AM
Ich

4 
3,505 
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 
3,504 
i dont know if this is the right section for this but here goes my doubt,I read that the rest mass of a photon is...

Apr2206 05:04 AM
pmb_phy

44 
3,503 
Where can we find the prove of universe expansion from the equations of General Relativity?

Apr807 02:25 AM
pervect

1 
3,503 
Hello all. First time posting here.
I have a basic understanding of special relativity and I have few questions...

Dec2009 05:01 AM
yuiop

16 
3,503 
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 
3,503 
As stated in SR, mass of the object increases with its velocity right?
Lets assume that all the objects in the...

Jan1812 04:03 PM
SHISHKABOB

36 
3,502 
So I read that time is actually relative, and that if I had a clock in orbit around earth and a clock on earth, that...

Mar613 10:53 AM
ZapperZ

26 
3,500 
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 
3,499 
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 
3,497 
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 
3,495 
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 
3,495 
i was hoping someone could explain why light speed even enters the e=mc2 equation. energy equals mass times the speed...

Mar2404 10:37 AM
da_willem

4 
3,494 
The relative motion and the relative time of any inertial system to another one is in literature available (to me)...

Sep1408 02:47 AM
atyy

46 
3,494 
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 
3,493 
Can anyone tell me the date and the journal of Eddington's original paper that suggested the new coordinate system to...

Jan2809 05:25 PM
dlw181

2 
3,493 
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 
3,492 
Can anyone point me to a good source using the Schwarzschild metric that gives Einsteins predicted result of the...

Jun2010 06:55 PM
Passionflower

36 
3,492 
I would like to create (with everyone's help) a list of experiments etc that support SR and GR.
These should be...

Jul204 03:05 PM
zefram_c

28 
3,491 
I read about Einstein's hole argument and about diffeomorphism. Pasive diffeomorphism is changing of coordinate...

Mar2512 01:02 PM
momchil

13 
3,486 
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 
3,484 
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 
3,483 
Hi,
Not sure if this is the correct forum for it. Pls move if not.
I've read and heard several times about...

Nov211 06:09 AM
Chalnoth

30 
3,483 
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 
3,482 
I see a lot of stuff on the internet from people that some would call "cranks", disputing SRT etc. (Personally, I try...

Feb910 09:39 PM
dr_k

27 
3,477 
Lorentz Transformation says
x'=\frac{xut}{\sqrt{1u^2/c^2}}
Does its derivative
...

Jun704 06:31 AM
hemmul

1 
3,474 
The time travel cliché of the “Grand Father” paradox is logically flawed and has driven the notion of the multiverse...

Nov1309 12:20 PM
frankinstein

33 
3,474 
In black hole physics and GR, what does the term back reaction means?

Dec3005 04:00 AM
Garth

1 
3,473 
My limited understanding of relativity tells me that "gravitational forces" are really just due to the curvature of...

May806 03:51 AM
Ich

16 
3,473 
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 
3,473 
In section 2.4 of Schutz's, "A First Course in General Relativity", he states that the conservation of fourmomentum...

Jan810 10:45 PM
snoopies622

27 
3,473 
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 
3,472 
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 
3,471 
Let's suppose that on Earth I have two devices which permits me to detect the gravitation produced and electromagnetic...

Jun2912 08:51 PM
PeterDonis

25 
3,471 
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 
3,470 
For the longest time educators had repeatedly taught me of the problem with gravity. We have four fundamental forces...

Mar2212 03:59 PM
Mark M

11 
3,469 
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 
3,467 
This has bothered me for some time. I must be missing something.
Photons, being the massless particles that they...

Aug1007 02:55 PM
Timo

6 
3,467 