All Questions
Tagged with newtonian-gravity general-relativity
227
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When is it appropriate to say Newtonian gravity is a force? When is it not appropiate? [closed]
Please help me understand the notion of force when it is applied to Newtonian gravity. From my understanding forces in physics involve interactions with at least 2 objects and can cause an ...
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Is there a deeper relationship between symmetry and gravitational potential comparing Newton's and Einstein's gravity?
In this question, see Why is general relativity in (2+1) dimensions different from cylindrical systems in (3+1) dimensional GR?, it is mentioned
"The gravitational potential Φ of an infinite rod ...
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EM 4-potential vs gravity 4-potential?
In classical field theory, the electrostatic and gravitational fields have very similar differential forms:
$$\vec \nabla\cdot \vec{E}=\frac{\rho}{\varepsilon_0}$$
$$\vec \nabla\cdot \vec{g}=-4\pi G\...
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Quantised Newtonian potential as an operator in non-relativistic QM [closed]
Suppose we have two slowly moving (effectively static) masses $m_1,m_2$, interacting through gravity, that are not occupying a definite state of position i.e. that matter is being treated quantum ...
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Einstein's equation of gravitation field [duplicate]
I'm looking for the reason why there is the number eight $8$ at the r.h.s. of EI:
$$R_{\mu\nu}-\frac{1}{2}Rg_{\mu\nu}=\frac{8\pi G}{c^2}T_{\mu\nu}.$$
My attempt was to take the limit of this equation ...
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How does gravity act and propagate in a 2+1D universe?—Newtonian versus general relativity
In a hypothetical 2+1D universe:
if we apply the Newtonian concept of gravity, we might expect that the gravitational force between two mass points with a distance of $r$ would diminish linearly with ...
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References on Newton-Cartan Gravity
I'm interested in learning a bit about Newton-Cartan gravity, and I would like some references on the topic. I am already familiar with differential geometry and general relativity, so those could be ...
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When does Newtonian physics fail?
When does Newtonian physics fail?
The answer by Zo the Relativist to the question How accurate is Newtonian Gravity? includes the statement:
The key point is that Newtonian physics fails when, ...
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Physical relevance of the $ij$ components of the Einstein field equations in the Newtonian limit
In the weak field limit of general relativity (with matter described by a perfect fluid consisting only of dust), we have the following correspondences:
$00$-component of the Einstein field equations ...
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Why can Newtonian gravity provide the correct value of the Schwarzschild radius? [duplicate]
By using Newtonian gravity, we can equate the kinetic and potential energy of a test mass in order to obtain the escape velocity of an object from a large mass $M$:
$$\frac{1}{2} m v^2 = \frac{GMm}{r}$...
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What's the Newtonian potential in 2+1 gravity?
I understand that there are no propagating degrees of freedom (i.e. gravitational waves) in 2+1 dimensions. There are a couple of arguments to show this. One is to count degrees of freedom of general ...
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Gravitational effects on a celestial body and the difference between a pendulum and a regular clock
Imagine a planet with the same properties as Earth, this time moving in an elliptical orbit around a heavy star of a large number of solar masses. Also imagine that the surface of this planet is as ...
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Derivative of Ricci tensor and Euler-Lagrange equations ambiguity
I'm currently working in a problem about formulating a Lagrangian for Newton-Cartan theory and i'm currently proving if it works.
In order to do this i'm required to compute the derivative of the ...
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Does General Relativity imply greater accelerations than Newtonian gravity in strong gravitational fields? [duplicate]
Does General Relativity imply greater accelerations than Newtonian gravity in strong gravitational fields, such as at 2 m/s^2?
Do the general relativistic corrections add up to more "gravity"...
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How close was Maxwell to general relativity? [closed]
In a recent paper by Accolierastro's recent video, she goes back to Maxwells seminal paper on electromagnetism, and the section on gravity. In Maxwells paper, he notes the similarity between the lines ...
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