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Feb2313 08:40 AM
ZapperZ

1 
40,988 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
40,650 
Spacetime is supposed to be one unity making time in a way equivalent to spacial dimensions. Of course in the metric...

Oct1509 02:41 AM
twofishquant

4 
1,667 
I know that seems like a stupid question to ask. But I was watching a video on relativity and thought for a moment how...

Jun210 10:04 PM
Geigerclick

16 
1,667 
Is it possible for a black hole to exist in a reference frame and not exist in another?
I did some naive calculations...

Jun510 01:15 PM
Naty1

8 
1,667 
I had 1 year ago a little discussion with DaleSpam about the short Lorentz derivation (triangle) if a photon alone...

Apr1613 06:38 PM
digi99

16 
1,667 
I am a practicing EE who has used the standard Doppler shift equation for thirty years in radar design; therefore, I...

May1504 10:18 PM
David

3 
1,666 
Hi,
I was wondering if somebody could tell me in what way the following paragraph is incorrect (if it is). Thanks.
...

Aug2004 06:04 PM
pervect

12 
1,666 
I've just been thinking (prolly a bad idea): Lorentzian metrics aren't actually metrics at all are they? Infact...

Nov1604 02:03 PM
jcsd

5 
1,666 
Ok, so light is both a wave and a particle. That's fine, I accept that.
If a photon is a particle it must therefore...

Jul1808 11:27 AM
bernhard.rothenstein

5 
1,666 
ok, if when we look at a planet that is say 100000 light years away, and we can see it emitting light, and that light...

Nov2711 04:28 PM
ianpr

14 
1,666 
Hello all,
Brand new member here. I am trying to fully understand the different kinds of masses, i.e. rest mass,...

May2014 04:40 PM
berkeman

29 
1,666 
I'm having trouble understanding the question below. Conceptually I don't see how there would be a difference in...

Dec1806 04:19 PM
RandallB

2 
1,665 
Why has light same velocity when measured from any frame?
I know about Maxwell's theoritical deduction (but not...

Dec2707 10:22 PM
peter0302

2 
1,665 
I know there have been some frame dragging effect experiments, with the GPB being performed at the moment. Which other...

Feb305 03:59 PM
matt.o

8 
1,664 
how come when nasa speaks of the either the space shuttle or the ISS, they speak as if they have left the effects of...

May1209 06:00 PM
neh4pres

6 
1,664 
Does the curvature of spacetime describe gravity or tidal force?

Feb2709 04:13 AM
A.T.

10 
1,664 
I posted an LHC question a while back but did not get a reply. I'll ask a somewhat different, simplified and more...

Feb711 07:37 PM
teve

2 
1,664 
I have a broader question on this  is mass at all properly defined in GR context, including rest mass or socalled...

Jan613 08:27 AM
DaleSpam

12 
1,664 
What is the approximate fractional difference in time measured between a quartz watch crystal resonating either...

Mar1007 12:25 PM
Mentz114

3 
1,663 
Gravitational waves travel at the speed of light. So do they also bend around massive objects? If we had an extremely...

Jan1109 01:40 AM
granpa

7 
1,663 
Dear fellow relativiters,
I never fully got how to get from the field equations of Einstein's
R_{ \mu \nu} ...

Dec2712 05:48 AM
Madster

12 
1,663 
Trying to see the logic in deriving length contraction and time dilation using the Lorentz transformations and inverse...

Apr514 02:15 PM
ANvH

43 
1,663 
Hi everybody!!!
Is there someone that can help me to prove that
\omega^2Ek^2E=ip_0k\times E+i\omega p\times...

Dec608 06:55 PM
zwicky

2 
1,662 
i am now reading the book by landau
'the classical theory of fields'
it seems that to develop the relativity...

Jan2610 08:38 PM
wdlang

2 
1,662 
I've been learning about Special Relativity as a hobby for the past couple days and for the most part, I've been able...

Jun1010 12:31 AM
skycastlefish

5 
1,662 
What would happen to the spacetime fabric when two super massive blackholes collide. I know that they would orbit each...

Mar2812 07:07 AM
Vanadium 50

6 
1,662 
Does an electron in circular earth orbit emit radiation?

Apr1905 03:38 AM
yogi

4 
1,661 
Hello,
I have a question concerning general relativity. (go easy  I have only knowledge from general consumption...

Jun1908 03:37 PM
helix_angle

8 
1,661 
Alice is freefalling towards the event horizon (EH) of a black hole (BH) large enough such that local tidal forces...

Feb1411 03:17 PM
DrGreg

15 
1,661 
I found this article: http://www.csa.com/discoveryguides/gravity/overview.php
The article says gravity moves at...

Jul2511 09:17 PM
bcrowell

7 
1,661 
Hi,
I was looking up the formula for this on wikipedia and it said that the frequency shift is:
\frac{\sqrt{1 ...

Oct1713 12:25 PM
PeterDonis

12 
1,661 
I am having problems with this presentation of the train thought experiment. I actually think it's incorrect, but I'm...

May210 11:54 AM
Jerbearrrrrr

2 
1,660 
i posted this comment earlier today, but in a wrong part of this forum.
if the fabric of space is expanding...

Sep1309 03:52 AM
cary cato

26 
1,659 
Hi everyone,
I'm new and this is my first post here.
I'm 37 yo, I'm italian so forgive my english.
My question...

Nov809 03:32 AM
A.T.

20 
1,659 
It is wellknown that Newtonian's law of gravitation
\Phi(\vec{r}) = \frac{Gm}{\vec{r}  \vec{a}}
for the...

Jun2314 07:45 AM
stevendaryl

20 
1,659 
This may have come up before but I havent seen it and dont know the answer.
What if the twins started out in...

Nov1608 04:05 AM
MeJennifer

3 
1,658 
Hi all, I have been struggling (really) with this and hope someone can help me out.
I would just like to compute...

Jul2511 02:12 AM
hanson

5 
1,657 
Please feel free to move this to the correct forum.
After doing some reading, I've found that Electromagnetic...

Sep3012 08:59 AM
Bill_K

6 
1,657 
Popular Science has been running an article about Sonny White, a prominent engineer at NASA's JSC.
White has been...

Apr613 06:46 AM
tade

14 
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I understand that the speed of light can be slowed down when it passes through different mediums.
I also understand...

Dec2213 08:26 PM
JVNY

24 
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I was wandering through the net when I came to know that the Newtonian gravitation suffers discrepancies at some...

Jan2912 08:11 PM
JPBenowitz

3 
1,656 