All Questions
Tagged with computational-physics general-relativity
94 questions
2
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1
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79
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M-R curves using Polytropic equation of state unexpected behavior [closed]
I'm trying to solve Tolman-Oppenheimer-Volkoff (TOV) equations in the original form $\{p^\prime,m^\prime\}$, using Mathematica, but I'm having some trouble getting the M-R plots since they seem to ...
- 21
0
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0
answers
77
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I'm doing my project work on astrophysics. So what i want to find how much black hole grows over time
So problem in the code I have to find the velocity of gas that falling in the black hole at the point of event horizon,from this i can find the increasing $dm$ mass from Bondi equation over $dt$ time. ...
1
vote
0
answers
49
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Constructing Embedding Diagram of Reissner-Nordstrom Dihole [closed]
Is it possible to create embedding diagrams of $\phi=constant$ slices of axisymmetric two black home spacetimes, like the Reissner-Nordstrom dihole?
$d\Sigma^2=U(x,y)^2(dx^2+dy^2)$
I ask because the ...
- 343
0
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0
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47
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Topological illustration of spacetime dilation: which function should I use for isometric lines spacing?
Scientific popularization, when it comes to illustrating spacetime dilation around massive objects, often relies on the description of a two-dimensional square-grid, which can be regarded as a cross-...
1
vote
1
answer
107
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Numerically solving frame-dragging equation in Hartle-Thorne formalism
I'm trying to write a Python code to implement Hartle-Thorne approximation formalism for rotating neutron stars. In this formalism, I am required to solve the following second order differential ...
- 13
1
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0
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65
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Inconsistency in numerical and slow-roll solutions of Mukhanov-Sasaki equation during Inflation
from my lectures in cosmological inflation, we derived the Mukhanov-Sasaki equation and its initial condition (Bunch-Davies). From here, it was of our interest to find a numerical solution of the ...
2
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0
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120
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Numerical Relativity for Computer Scientists
What resources on numerical relativity/simulation would be suitable for a primarily theoretical computer science background [algorithms analysis, complexity theory, etc.]? Importantly, while I'm ...
2
votes
2
answers
346
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In general relativity visualizations what are the equations of grids?
I am wondering what curved 3D grids in GR outreach correspond to in equations. How would I compute such a curved grid if I know the metric tensor $g_{\mu\nu}$ in every point of space? What would be ...
- 1,255
0
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1
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75
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Math and Pseudo code paper on black hole binary simulation
I want to do a short practice to see how mass evolve space and how space curvature evolve mass distribution.
Most of the GR simulations were rather complicated but I think the black hole binary had ...
1
vote
0
answers
137
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Komar energy using Mathematica [closed]
I want to check Komar conserved quantities for Kerr Newman metric using Mathematica. Is there any way to write a programming code for this?
Can anyone help me?
2
votes
1
answer
2k
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Numerically solving the TOV equations: how to find the max radius and mass?
I'm solving the TOV (Tolman-Oppenheimer-Volkoff) equations using Mathematica 13.2, and I'm having some issues at finding the outer radius $r_{\text{max}}$ and mass $M_{\text{max}}$ of the spherical ...
- 7,805
2
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0
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72
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Extreme Kerr render engine issue
So, me and a friend have been working on a Kerr render engine. It uses the Kerr metric of general relativity to draw the image of a black hole. Our current results look like this;
The accounted for ...
- 308
3
votes
0
answers
133
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How to use Python to get mathematical expressions in General Relativity [duplicate]
I'd like to get the metric tensor that describes a non-rotating, uncharged, perfectly spherical black hole whose radius grows with time (it gains mass). For now, I have:
$g_{\mu\nu}=\begin{pmatrix}
-c^...
1
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1
answer
208
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Books and review articles for numerical relativity?
What are good books or review articles to read for numerical relativity?
I have read some textbooks on the 3+1 formalism (such as the book by Baumgarte and Shapiro), but I would like to have a ...
0
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0
answers
213
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Varying an action with respect to the metric in mathematica
I want to Varying an action with respect to the metric to obtain the Einstein equation $G_{\mu\nu}=k^2 T_{\mu\nu}$. Is there any way to do that in Mathematica? Can mathematica do that?
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