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Feb2313 08:40 AM
ZapperZ

1 
40,919 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
40,574 
Why do most explanations of the Twins Paradox claim that the twin on the space ship ages less because he is the one...

May108 04:51 AM
Phy6explorer

4 
1,701 
I'm putting this here since I'm a high school student who has only completed two years (preAP and AP) of introductory...

Apr3008 07:30 PM
pmb_phy

14 
1,779 
How is a photon's energy determine in relation to it's wavelength and frequency?
For example, 20hz vs. 400ghz...

Apr3008 07:16 PM
pmb_phy

4 
16,534 
I have scanned the simultaneity related posts and cannot find a succinct answer to a question I have  I accept that...

Apr3008 02:05 AM
neopolitan

280 
33,523 
Apparently some crackpot blew some $$ on a full page ad in a science magazine, claiming to show that there black holes...

Apr2908 08:54 PM
cristo

1 
900 
I quite often hear that GR is formulated in terms of tensors because laws of physics expressed in terms of tensor...

Apr2908 03:17 AM
jdstokes

21 
3,191 
And the 2nd question:
Do we know why is the speed of light 3*10^8 m/s? What determines this value? (I'm not asking...

Apr2908 02:18 AM
neopolitan

50 
15,016 
Hi.
I am learning special relativity and have decided to take Einstein's train example to practice some...

Apr2808 09:32 PM
morrobay

7 
4,364 
Assume 2 massive bodies are moving away from each other at high speed.
Since the gravitons which cannot travel at...

Apr2808 03:22 PM
lzkelley

8 
3,218 
(the story so far … I maintain that, inside an event horizon, there is a useful distinction between "space" and...

Apr2808 06:42 AM
DrGreg

34 
9,834 
Question:
1. A gravitational interaction causes two energy densities to accelerate towards each other.
2. This...

Apr2808 02:54 AM
redtree

19 
2,346 
I understand if this question sounds juvenile, because I thought of it after seeing a science fiction movie called...

Apr2808 01:35 AM
JesseM

2 
1,335 
Lorentz transformation shows that at the speed of light you divide by zero.
Photons travel at the speed of light,...

Apr2708 04:42 PM
lzkelley

1 
1,804 
http://psi.phys.wits.ac.za/teaching/Connell/phys284/2005/lecture01/lecture_01/node13.html
But what about induced...

Apr2708 04:17 PM
Dropout

3 
2,025 
Does it make sense for the Ricci Scalar to be a function of the spacetime coordinates?
In previous calculations I...

Apr2708 11:46 AM
lbrits

3 
2,907 
Does the Lorentz factor show up much (or at all) in general relativity? For instance, is it appropriate to use it as...

Apr2708 11:23 AM
shalayka

34 
3,952 
Hawking gave the black hole entopy equation:
(1) S_{BH} = {k c^3 \over 4G \hbar} A
where A is the surface area...

Apr2708 10:27 AM
Aether

2 
1,931 
What is the significance of solutions to nonhomogeneous wave equations for the scalar and vector potentials that...

Apr2608 11:53 PM
Stingray

13 
3,602 
Dear all,
I have a simple question.
Consider a long railway station. Say 2 km’s long. Station master put two...

Apr2608 11:21 PM
newTonn

108 
12,523 
I have two cathode ray tubes which generate the same amount of beam, i.e., one tube fires off x electrons per second...

Apr2608 08:42 PM
HarryWertM

9 
2,315 
I just want to verify that I have the right mindset here on the subject:
p=mv
You can increase the momentum as...

Apr2608 04:43 PM
pmb_phy

5 
1,698 
The axis of a spinning gyroscope is observed to be parallel to the x,y plane and at 45 degrees to both the x and y...

Apr2608 02:05 PM
Mentz114

11 
2,714 
Suppose you have a very strong, spinning disc with a diameter of say 10 km in length. At the centre the centripetal...

Apr2608 01:07 PM
yoyoq

15 
4,349 
According to GR, how do changes in the mass of an energy density become reflected in its gravitational field?
Is...

Apr2608 12:37 PM
Haelfix

9 
2,174 
Wheel experiment:
A balanced wheel has two large masses attached to the rim opposite each other with respect to the...

Apr2608 11:48 AM
Wizardsblade

9 
1,776 
Ok so I'm sitting at 0040 in the AM pondering this...is Time Dilation a constant. For example. It only takes an Object...

Apr2608 06:22 AM
Tweek

0 
2,482 
It occurred to me that I hadn't seen GR developed as a gauge theory in the same way QCD/electroweak are.
Are there...

Apr2608 12:31 AM
Haelfix

3 
3,049 
Why, when nearing the speed of light, do objects appear to be shrinking to someone in a different frame of reference?...

Apr2508 10:52 PM
rcgldr

1 
1,105 
question: do the effects of relativity that would manifest on objects approaching the speed of light (increasing mass,...

Apr2508 02:50 PM
Usaf Moji

10 
2,449 
Einstein v. Wheeler's Black Holes
John Wheeler who died earlier this month (13 April) not only coined the term ...

Apr2508 05:32 AM
pmb_phy

3 
1,643 
I was wondering about what experiments are planned or being done now to test the properties of gravity, such as is...

Apr2408 11:02 PM
Chaos' lil bro Order

3 
1,670 
i find in the literature
1. space is homogeneous and isotropic and time homogeneous, at least if judged by observers...

Apr2408 10:55 PM
Ken G

1 
1,249 
How can you have an inertial reference frame in which a body can remain at rest or move with constant velocity unless...

Apr2408 11:48 AM
hartlw

15 
3,581 
hi, I just heard about particles travelling faster than speed of light and somthing about cerenkov radiation. Is it...

Apr2408 10:27 AM
pam

4 
4,086 
Are gravitational waves considered "high frequency" or "low frequency"? Let's say, for example, compared to...

Apr2308 05:38 PM
Pacopag

0 
1,302 
I really do not understand WHY the equation is as it is. I understand what the equation means and how important it is....

Apr2308 04:15 PM
peter0302

5 
1,166 
I am new here
didnt find the reply to this before
I hope I get lorentz transformations right
he said, that...

Apr2308 12:34 PM
jtbell

5 
1,379 
1.) The tests of falling bodies in a frame under constant acceleration prove all masses accelerate to the floor at the...

Apr2308 08:40 AM
Chrisc

18 
2,400 
This is similar to the pole and barn paradox, but different enough that I'm not quite confident in my answer:
A...

Apr2208 03:07 AM
adimare

9 
1,917 
Hi,
I found myself trapped in a question on Special Relativity for 15 years now. Because of other new theories...

Apr2208 02:48 AM
olli

3 
1,291 