All Questions
8
questions
1
vote
1
answer
89
views
How does gravity act and propagate in a 2+1D universe?—Newtonian versus general relativity
In a hypothetical 2+1D universe:
if we apply the Newtonian concept of gravity, we might expect that the gravitational force between two mass points with a distance of $r$ would diminish linearly with ...
- 618
2
votes
2
answers
461
views
Newtonian gravity as curvature of space
Since Newtonian gravity is also indistinguishable from acceleration, it should be possible to formulate it as a curvature in space, right? For example, if a body changes velocities purely under the ...
- 6,355
-5
votes
1
answer
668
views
How can two objects with the same mass attract each other?
According to Einstein's theory of GR, two objects with the same mass won't atract each other, Why i'm saying this? The atraction according to GR happens because the objects with less curvature of ...
user319766
6
votes
9
answers
3k
views
According to general relativity planets and Sun bend the spacetime (explaining gravity), but does this hold true for smaller objects?
According to general relativity planets and the sun bend spacetime, and that is the explanation of gravity. However, does this hold true for smaller objects, like toys, pens, etc.? Do they also bend ...
- 119
0
votes
1
answer
277
views
Is it possible to express acceleration in a gravitational field as a logarithmic spiral?
The derivation starts from a logarithmic spiral:
$r=de^{b\theta}$
The lenght of a part of the spiral i calculated by:
$\int_{\theta_1}^{\theta_2} \sqrt{(\frac{dr}{d\theta})^2+r^2} d\theta$
From 0 ...
- 61
1
vote
1
answer
135
views
When is Newton's law of gravity recoverable in GR?
Often in a course in GR one can recover Newton's law of gravity under certain assumptions. weak field, slow moving particles etc. Is there a general method to recover Newton's laws of gravity for an ...
- 1,988
3
votes
1
answer
579
views
A few questions about Einstein's theory involving gravity
After watching a documentary about Einstein's theory of relativity, my mind was busy trying to comprehend how space bends when space is void and not made of matter. And additionally, does his theory ...
- 33
13
votes
4
answers
7k
views
Can a black hole be explained by Newtonian gravity?
In the simple explanation that a black hole appears when a big star
collapses under missing internal pressure and huge gravity, I can't see
any need to invoke relativity. Is this correct?
- 1,436