Tagged Questions
0
votes
1answer
59 views
Spacetime and Timelike Intervals
The difference between a “timelike” spacetime interval and a “spacelike” spacetime interval can be understood in the following way: If the spacetime interval between two events is timelike, there ...
-3
votes
0answers
35 views
effect of gravity on chemical reaction rates [closed]
a chemical reaction is done on earth in very vacuum and that chemical reaction is also done in space so that gravity higgs field not affect that reaction.
Which reaction will be fast wrt gravity and ...
1
vote
1answer
85 views
How much time has passed for Voyager I since it left the Earth, 34 years ago?
34 years have passed since Voyager I took off and it's just crossing the solar system, being approximately at 16.4 light-hours away. How much time have passed for itself, though?
1
vote
1answer
73 views
Could light travel more slowly than the “universal speed limit”? Could this imply quantization of spacetime?
One description of relativistic effects that I've heard/read goes something like this:
Everything moves through spacetime at a constant speed. An object's direction of travel through spacetime can ...
-1
votes
1answer
97 views
How do photons experience time? [duplicate]
I know that as velocity approaches the speed of light the time dilation shoots to infinity as shown below.
1)So I want to know how time is perceived from the point of view of the photon?
2)Since ...
3
votes
3answers
305 views
Why do clocks measure arc-length?
Apologies in advance for the long question.
My understanding is that in GR, massive observers move along timelike curves $x^\mu(\lambda)$, and if an observer moves from point $x^\mu(\lambda_a)$ to ...
1
vote
1answer
57 views
Are branes in 4D-spacetime moving, or are they static?
Given that a worldline, worldsheet, worldvolume, are representation in a 4D-spacetime of a point particle, a string or a brane, respectively, I was wondering if those objects necessarily have to be ...
-9
votes
1answer
200 views
Why are we talking about space curvature as if we know what space is? [closed]
1) Why are we talking about space curvature as if we know what space is?
Every question about gravity seems to evoke an answer involving "space curvature" which seems like an undefined placeholder ...
0
votes
0answers
54 views
Space-time & solar mass
Does the space-time curvature described by Einstein have any affect on the accuracy of our determination in the age of a star or globular cluster? How does this affect our interpretion of how old we ...
2
votes
4answers
313 views
Reducing General Relativity to Special Relativity in limiting case
I understand that general relativity is applicable to gravitational fields and special relativity is applicable to case when there is no gravity. But is there a derivation on how to reduce General ...
2
votes
2answers
415 views
Nature of spacetime 4-vector and tangent space?
An entry level confusion about spacetime. I understand that a 4-vector describes a point or event in spacetime. But I've also read (Bertschinger, 1999) that re spacetime "we are discussing tangent ...
0
votes
0answers
234 views
How to formulate Lorentz invariance without the temporal dimension? [closed]
The role of "time" in fundamental physics has changed a lot in recent decades. Some physcists believe time is an emergent property rather than a most fundamental parameter of nature laws.
However, ...
