All Questions
17
questions
-3
votes
3
answers
76
views
Does Matter Cause Curvature or Vice-Versa [closed]
From the way explanations about gravity-acceleration-curvature equivalence are usually phrased here or elsewhere, it would appear many or most think that matter causes space-time curvature.
I cannot ...
0
votes
0
answers
49
views
How the equivalence principle leads to the idea of curved spacetime? [duplicate]
In wikipedia https://en.wikipedia.org/wiki/Equivalence_principle, there are three forms of equivalence principle ( equivalence of gravitational and inertial mass ) :
Weak version (Galilean) :
The ...
1
vote
0
answers
146
views
Equivalence Principle: Uniform to Non-uniform gravitational fields
2Einstein in his 1916 GR paper describes the equivalence principle and makes a case for general relativity i.e a person in a non-inertial frame is equivalent to a person in a uniform gravitational ...
0
votes
3
answers
163
views
Would I be able to tell if I was inside a piece of distorted space? Are objects distinct from spacetime?
If one could hypothetically stretch / squash / in some way distort a piece of space, an outside observer could tell by looking at the distorted object/space that it had changed because the difference ...
1
vote
1
answer
85
views
Why is the situation of 'accelerating frame in flat spacetime' not equivalent to 'staying stationary in a constant gravitational field'?
One popular form of the equivalence principle states that the effects of a gravitational field in a small enough region of spacetime are indistinguishable from those of being in a uniformly ...
0
votes
1
answer
98
views
Confusion about the proper time interval along an arbitrary worldline
Let us consider the worldline $x^\mu(\lambda)$ of an observer moving in an arbitrary manner (i.e. possibly non-inertial). If we want to write down the proper time interval measured by that observer ...
13
votes
6
answers
2k
views
Is spacetime curved in a near-earth-free-falling-object's frame of reference?
If I float motionless in outer space, I will measure spacetime to be approximately flat.
By the equivalence principle, I will get flat spacetime if I am free falling near earth.
Is this right? ...
5
votes
5
answers
763
views
Equivalence principle doubt
There is something about Einstein Equivalence Principle that I don't quite get. This is my reasoning:
Equivalence principle $\rightarrow$ locally, acceleration is equivalent to a gravitational field
...
0
votes
1
answer
309
views
Is the gravitational field an illusion, a by-product of geometry? [duplicate]
The principle of general covariance from the Equivalence Principle (EEP) tells us that there is no way in principle to locally distinguish between an inertial acceleration and the effects of a ...
2
votes
3
answers
754
views
Uniform Gravitational Field = No Gravitational Field?
I'm reading Geroch's lecture notes on GR, and in the first chapter he makes the following assertion:
People inside an elevator freely falling in a uniform gravitational field cannot distinguish ...
2
votes
1
answer
285
views
Does curved spacetime arise from inhomogeneity of gravitational field?
In general relativity textbooks such as Sean Carroll's Spacetime and Geometry, there is often a line of reasoning that goes like this:
Strong equivalence principle states that free falling frames are ...
2
votes
2
answers
479
views
Time dilation and freefall (follow up and simplification) [closed]
A person is four miles up in the atmosphere, and freefalls towards earth. Another person is standing on earth, watching them come down. During this period of freefall, which person experiences more ...
1
vote
2
answers
166
views
Falling with same acceleration and meaning of gravity
My question is what does falling with same acceleration has to do with what Einstein concluded concerning the gravity in terms of the curvature?
2
votes
1
answer
3k
views
How exactly and WHY does matter affect space-time? [closed]
According to general relativity, inertial mass and gravitational mass are the same, and all accelerated reference frames (such as a uniformly rotating reference frame with its proper time dilation) ...
4
votes
6
answers
2k
views
Can we think of gravity as space itself moving?
So if you move through space with a constant acceleration you experience longer time dilation than when you're at rest, but you also experience the same time dilation when you're under the effect of ...