All Questions
15
questions
1
vote
3
answers
77
views
Spacetime effects on human scale objects?
For a human standing upright on the earth, gravity would have a different value at the feet than at the head, and gravity influences the flow of time. Does the difference in the flow of time cause any ...
1
vote
3
answers
1k
views
Does a uniform gravitational field exist? Is there any acceleration in a uniform gravity field?
This question arose in the Space Exploration forum, by non-physicists, so it likely sounds naïve. The question involved the plausibility of using a very strong gravitational field to accelerate an ...
0
votes
1
answer
492
views
Are gravitational waves produced only when a mass accelerates? [duplicate]
Why? They are not a form of EMR, are they.
Or are the rapidly changing ones the only ones we can detect?
5
votes
5
answers
1k
views
Gravity is not a force - how does "accelerating up" work for the entire earth? [duplicate]
So this question has been bothering me for several days now. I've seen many YouTube videos on how "Gravity is not a Force", but no one seems to offer a simple explanation on how does this &...
1
vote
2
answers
170
views
Bell's paradox but with acceleration caused by a uniform gravitational field rather than rocket engines
Bell's paradox has in the past been the topic of quite heated discussions. It is posed in the context of a silk thread connecting two identical rockets whose engines are ignited at the same instant. ...
1
vote
1
answer
124
views
How does the spacetime curvature cause an object to attract towards the ground? [duplicate]
An object moves at a constant speed relative to the local spacetime but due to the warped spacetime it appears as if accelerating. How does spacetime curvature exactly causes this effect?
2
votes
1
answer
184
views
Why can gravitational acceleration not be detected by experiments
I was doing research into how $G$ forces are calculated, and I was told that they show all acceleration that can be "sensed" by humans (i.e. all non-gravitational acceleration).
This ...
0
votes
1
answer
55
views
Moving from acceleration- gravity equivalence to general relativity [duplicate]
Einstein's happiest thought of his life led to so called acceleration-gravity equivalence by simply imagining a man free falling. This simple thought led Einstein to formulate his general theory of ...
6
votes
3
answers
1k
views
If gravity is simply a curvature of space, why does it accelerate objects? [duplicate]
I understand how an object moving through space would be affected if gravity were a curvature of space as opposed to being a force. However, I do not understand why this creates a "pull" on ...
1
vote
1
answer
104
views
How two observers on different gravitational fields would observe each other?
As far as I know (from what I have heard) time passes differently (faster or slower) depending on the gravitational field of the observer (or an acceleration). So my question is, if an observer was ...
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 ...
1
vote
3
answers
2k
views
Why does gravity warp space time but not acceleration?
In general relativity, the presence of gravity warps space-time yet clearly me accelerating will not warp space-time. It is hints at in one of the comments of this answer that acceleration bends world ...
8
votes
1
answer
2k
views
Does an object creates gravitational waves when only accelerating in one direction?
I know from reading about the gravitational waves detected by Ligo, that when an object has angular acceleration, it produces gravitational waves.
I'm wondering if an object creates gravitational ...
6
votes
3
answers
754
views
When is a circle not a circle?
Imagine a 2D uniform circular motion of constant magnitude but changing direction in an area of zero g. The forces will be equal all the way round - it will be a perfect circle.
Now imagine the same ...
4
votes
3
answers
426
views
Is acceleration caused by curvature or space or time or both?
I'm trying to get a hold of the idea of gravity in general relativity and spacetime. I've seen plenty of demonstrations of the rubber mat analogy to describe gravity and spacetime curvature. Is this ...