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Feb2313 08:40 AM
ZapperZ

1 
42,763 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,405 
Suppose we have an observer at a large distance from the event horizon of a black hole, pouring matter towards the BH...

Dec805 01:16 PM
JesseM

6 
2,151 
Hi.
The higher the velocity of an object the more energy this object has. Velocity is purely relative. When I move...

Dec2810 10:30 AM
lightarrow

12 
2,151 
Hi,
I've been listening to a Professor Jim AlKhalil's scipod on time travel. I think this guy is bloody...

Nov1711 06:10 AM
Dickie_Boy

9 
2,151 
I understand that the time dilation at the surface of the Earth is the same as for an object moving in space at...

Nov1711 02:33 PM
Shaw

0 
2,151 
What is the simplest derivation of the transformation rules for Maxwell's equations in special relativity?
I'm...

Apr514 02:14 AM
Fredrik

17 
2,151 
There is a classic result by Tolman, Ehrenfest, and Podolsky that in classical GR, the interaction between pencil...

Jul1711 03:17 PM
yuiop

18 
2,150 
I think I have come across something that invalidates something one of my Physics professors said back in college,...

Jun2514 09:23 PM
DaleSpam

27 
2,150 
Consider a 4coordinate system x=(x^0,x^1,x^2,x^3), x^0 plays a role of time, x^1, x^2, x^3 are some kind of space...

Aug1109 10:01 PM
vin300

20 
2,149 
I thought I'd present some plots for the Ferminormal coordinates (only in the rt plane) for someone falling into a...

Nov1910 03:37 AM
pervect

12 
2,149 
I like to do whirlies with the kids down in my local park. I grab them by the feet and I spin them in a circle with...

Apr908 07:55 PM
michael879

24 
2,148 
What is the rationale for the sign convention in the spacetime 4vector? How is it related to the sign convention in...

May108 08:51 AM
pmb_phy

9 
2,148 
Hi,
it's very interesting, that many parts of special relativity were developed before Einstein by Lorentz, Larmor...

May1208 01:01 PM
peter0302

10 
2,148 
According to my physics textbook, the equation E^2=\left(mc^2\right)^2+\left(pc\right)^2 suggests that a particle may...

Jul411 12:09 PM
Parlyne

15 
2,148 
Any faster than light signal can create backward time effect by means of some frames seeing the signal go to the past...

Nov2111 08:31 PM
Fredrik

13 
2,148 
Okay, so I'm a total noob at physics but I'm interested in it, so please bare with me... It's discribed that space is...

Dec3106 01:14 PM
pervect

1 
2,147 
Does space limit the velocity of light or is it the formulas of relativity that limit the velocity of light?
Isn't a...

Oct1613 10:13 AM
kaplan

11 
2,147 
Matt Visser has a neat derivation of the Schwartzschild solution of Einstein's equations from Newtonian gravity, the...

Aug2910 02:31 AM
JesseM

6 
2,146 
Hello!
My name is Alexandru, i am from Romania student at Mechanics University. I am working on a project and i...

Aug1408 01:09 PM
George Jones

13 
2,146 
Hey guys, I've been trying to find out about the expected effect of acceleration and/or motion on a pendulum clock; I...

Feb1512 05:50 AM
harrylin

9 
2,146 
Can someone tell me what the numerical value for the entropy of a black hole of five solar masses would be?
Is it a...

Aug604 08:21 AM
kurious

2 
2,145 
I do not know the details, but I have read that some theories allow backwards time travel using wormholes. Backwards...

Dec909 11:56 PM
Dmitry67

18 
2,145 
In the following article
...

Jul2411 09:45 PM
bcrowell

9 
2,145 
I have posted links to the original papers on Relativity : the Special and General Theory made by Albert Einstein
...

Jan506 02:32 PM
Tom Mattson

3 
2,144 
Okay, I know there is observational evidence for spinning black holes, so therefore I must be confused about...

Oct1711 12:08 PM
Constantin

6 
2,144 
I understand that magnetic force is a relativistic effect of electric force.
Is there a force which is the...

Jul308 12:30 PM
rbj

12 
2,144 
Am not sure if this belongs more in quantum physics or in GR, it's at the intersection of the two.
If I understand...

Jul1508 12:20 PM
George Jones

9 
2,144 
Roger Penrose is reported to have said:
And I understand that, in Minkowski spacetime, the relative velocity...

Nov2909 03:01 AM
Grimble

7 
2,144 
Let us say we have a very long glass that has a uniform square cross section. Its long axis is aligned with the x...

Mar1812 05:20 PM
yuiop

18 
2,144 
Ok. There are some concepts here that I am having trouble reconciling.
I would first like to "stipulate" that for...

Mar1408 07:12 AM
tinytim

9 
2,143 
If mass of a moving object is as below:
http://upload.wikimedia.org/math/0/2/a/02a09d2ef62edff59459f51b329877df.png...

Sep2211 05:10 AM
harrylin

8 
2,143 
I have encountered a difficulty which arises from my attempt to combine non collinear Lorentz transformations in...

Jul1214 09:46 AM
nixed

12 
2,143 
i dont understand a problem :confused:
if i two photons A & B travel in a straight line but in opposite directions...

Jul1206 01:32 PM
robphy

15 
2,142 
If two objects, let's say two pool balls (or giant balls of neutronium for that matter), are placed in a closed...

Sep1108 09:20 PM
MeJennifer

21 
2,142 
This is probably a repeat question from somone somewhere, but here goes. Please fill in the blanks. I don't need a...

Jul3009 04:14 PM
solveforX

22 
2,142 
Dear Forum Users,
I am a graduate student in Mathematics and not physics, so please bare with me. Also, I know that...

Feb1913 05:18 PM
FeynmanIsCool

30 
2,142 
This is another version of bell’s spaceship paradox.
Consider two spaceships A & A’ separated by a distance L, and...

Oct313 09:18 PM
DaleSpam

12 
2,142 
I imagin this thought experiment: a train which travels with the speed of light is trying to enter a tunel which has...

Sep907 03:30 PM
Doc Al

7 
2,141 
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 
2,141 
what is to top speed that this rocket can achieve as seen by a stationary observer? Also if you look at the...

Jun508 01:10 PM
neh4pres

22 
2,141 
As you will see this is my first post so I apologize if I have chosen the wrong subforum. My academic training...

Feb2612 10:10 AM
childej

8 
2,141 