All Questions
340
questions
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51
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Does gravity accelerate you towards the geodesic of light between you and the mass?
If there's a planet far away, you will accelerate straight towards it due to gravity. If you place a Schwarzschild black hole right in the middle between you and the planet (the distance between the ...
8
votes
5
answers
1k
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Do you always experience the gravitational influence of other mass as you see them in your frame?
You see a galaxy far away. That galaxy is attracting you with a certain amount of gravity. I'm wondering if the gravity influence of the galaxy on you, as measured by you, always ends up being what ...
1
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0
answers
48
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How can you use gravity while trying to model gravity? [duplicate]
So consider the usual pop-science spacetime model, a bowling ball on a trampoline. Apparently, the ball should sink into the trampoline, causing a dip in the fabric which causes nearby objects to fall ...
1
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1
answer
104
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Does dark matter have mass?
When trying to understand what dark matter is, it is helpful to know that some properties of it can already be derived from various observations, such as, it only interacting via gravity and no other ...
-7
votes
1
answer
138
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So just because gravity "merely" bends space and isn't "really" a force at a distance - isn't it still a thing at a distance? [closed]
As a preamble, just for clarity as far as I can remember (I was awfully drunk) I have a degree in physics, math and comp sci: my point is "here's a probably stupid question at the level of person ...
19
votes
6
answers
8k
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If gravity is not a force, what makes massive objects spheroid?
For most of my life, the explanation given for why celestial bodies like stars, planets, etc. are round is due to gravitational force. Simply put, if an object has enough mass, it will, in turn, have ...
1
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1
answer
89
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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 ...
-1
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1
answer
83
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Apparent paradox in general relativity wrt relative gravity, spacetime curvature and time dilation [closed]
Imagine Alice is near a massive black hole and Bob is on the Earth.
Obviously their gravitational fields are different for each other. In other words, their spacetime is flat for themselves but curved ...
2
votes
2
answers
111
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Why does the warping of spacetime make objects move closer together?
I understand why the warping of spacetime affects moving objects, but why would it affect stationary ones if it even does? Would two completely stationary objects not move closer together because they ...
0
votes
1
answer
59
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Are gravitons suggested as the cause of matter curving space?
My understand is that GR says that mass curves space but it does not say why or how this occurs. Is the idea of gravitons that they are the entities that actually affect space?
-2
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2
answers
115
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What is the current most widely-accepted explanation of gravity? [closed]
What do physicists typically say gives gravity the ability to act on a pair of objects?
I am not asking for a description of gravity as a scalar field, but rather what the current accepted theory is ...
0
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0
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73
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Are there any ways to conceptualize the relationship between gravity and space-time other than curvatures?
This might sound like a random question, but it came to me while I was trying to conceptualize the size of the universe and started thinking of entire galaxies resembling grands of sand floating ...
0
votes
2
answers
77
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Gravitational field of the star changes the paths of light rays, how is this observed during eclipse?
The gravitational field of the star changes the paths of light rays in space-time from what they would have been had the star not been present. I understand that the light cones are bend slightly ...
1
vote
1
answer
97
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Limit of gravity
Is there any limit to the bending of spacetime due to gravity?
I have been reading about wormholes and how they bend spacetime and connect two systems. But if there is no limit to gravity, we can ...
-2
votes
2
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71
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Shouldn't there be a gravitational field without any mass in our 3d space? [closed]
Imagine there is a Neutron star Displaced a small distance from our accessible 3d slice in the direction transverse to that 3d slice. It will bend the space around it. It will also bend the space of ...