All Questions
132
questions
81
votes
17
answers
59k
views
How exactly does curved space-time describe the force of gravity?
I understand that people explain (in layman's terms at least) that the presence of mass "warps" space-time geometry, and this causes gravity. I have also of course heard the analogy of a blanket or ...
- 913
21
votes
5
answers
6k
views
How does "curved space" explain gravitational attraction? [duplicate]
They say that gravity is technically not a real force and that it's caused by objects traveling a straight path through curved space, and that space becomes curved by mass, giving the illusion of a ...
- 2,172
21
votes
6
answers
4k
views
Better explanation of the common general relativity illustration (stretched sheet of fabric)
I've seen many science popularisation documentaries and read few books (obviously not being scientist myself). I am able to process and understand basic ideas behind most of these. However for general ...
- 313
161
votes
6
answers
55k
views
Why would spacetime curvature cause gravity?
It is fine to say that for an object flying past a massive object, the spacetime is curved by the massive object, and so the object flying past follows the curved path of the geodesic, so it "appears" ...
- 1,926
36
votes
8
answers
6k
views
Does the curvature of spacetime theory assume gravity?
Whenever I read about the curvature of spacetime as an explanation for gravity, I see pictures of a sheet (spacetime) with various masses indenting the sheet to form "gravity wells." Objects ...
- 6,044
71
votes
2
answers
9k
views
Is spacetime flat inside a spherical shell?
In a perfectly symmetrical spherical hollow shell, there is a null net gravitational force according to Newton, since in his theory the force is exactly inversely proportional to the square of the ...
- 2,173
38
votes
3
answers
6k
views
Why is spacetime curved by mass but not charge?
It is written everywhere that gravity is curvature of spacetime caused by the mass of the objects or something to the same effect. This raises a question with me: why isn't spacetime curved due to ...
- 5,481
11
votes
5
answers
12k
views
Does a moving object curve space-time as its velocity increases?
We always hear how gravity bends space-time; why shouldn't velocity?
Consider a spaceship traveling through space at a reasonable fraction of the speed of light. If this spaceship, according to ...
- 329
47
votes
15
answers
8k
views
Why does the speed of an object affect its path if gravity is warped spacetime?
I think I understand the idea of thinking about gravity not as a force pulling an object towards another object but instead a warping of space so that an object moving in a straight line ends up ...
- 579
1
vote
2
answers
3k
views
Bowling ball on a rubber sheet analogy - what pulls the ball down [duplicate]
Possible Duplicate:
Does the curvature of spacetime theory assume gravity?
Since I read Cosmos long ago, I see the same analogy about the balls rolling on a rubber sheet used to explain how ...
- 113
15
votes
4
answers
29k
views
How energy curves spacetime?
We know through General Relativity (GR) that matter curves spacetime (ST) like a "ball curves a trampoline" but then how energy curves spacetime? Is it just like matter curvature of ST?
- 1,031
29
votes
5
answers
6k
views
Does curved spacetime change the volume of the space?
Mass (which can here be considered equivalent to energy) curves spacetime, so a body with mass makes the spacetime around it curved. But we live in 3 spatial dimensions, so this curving could only be ...
- 421
22
votes
4
answers
17k
views
How to measure the curvature of the space-time?
I know G.R. change our vision of space and time as a unique surface than can bend.
We can associate the curvature of the space-time as the gravity created by the mass of planets, stars... But how can ...
- 989
12
votes
6
answers
6k
views
The Fabric of Space-time?
I am not an academic in anyway, just someone interested in the story that is our universe. So my apologies if this isn't a well thought out inquiry.
I've been struggling with a concept for some ...
- 137
9
votes
2
answers
15k
views
Visualizing gravity in 3D
We've all seen the depiction of gravity bending space downwards, and so attracting objects into the dent it creates, cf. e.g. this and this Phys.SE posts. That's intuitive and makes a lot of sense, ...
- 415