All Questions
Tagged with scattering general-relativity
16
questions
4
votes
1
answer
197
views
Binary black hole merging condition
Assuming two black holes with the same rest mass $m$ collid coming from infinity with velocity $v$ and impact parameter $b$. Lets ignore spin at first. For which values of $v$ and $b$ would these ...
- 41
0
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0
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49
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How does the asymptotic metric fluctuation in $n \to m$ scattering relates to the soft factor in Weinberg's soft graviton theorem?
I'm reading arXiv: 1411.5745 [hep-th]. In Sec. 5, the authors show how the memory effect and Weinberg's soft graviton theorem are two faces of the same coin. I'm interested in understanding a specific ...
- 22.1k
0
votes
0
answers
58
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Making sense of Scattering of Impulsive Gravitational Waves
Consider the space-time diagram of KP-wave as shown below:
We see that two transverse plane fronted GW waves intersect at the point ($u,v$)=(0,0). The curvature comes with a delta function, except in ...
- 1,752
0
votes
0
answers
127
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What defines the gauge group for pure gravity?
Asymptotic symmetry of space-time corresponds to diffeomorphism transformation of physical space-time, which manifests as isometry near Conformal Boundary. Asymptotic symmetry can be defined using ...
- 1,752
2
votes
1
answer
103
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Will two passing bricks in empty space induce rotation in one another?
Two identical rectangular bricks with mass $m$ pass each other anti-parallel in empty space with a constant velocity $v$. Say the smallest distance between them is $s$. Assume the bricks to be aligned ...
- 500
-1
votes
1
answer
91
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Point of no return with two nearly colliding black holes [duplicate]
Consider two black holes traveling near the speed of light towards each other. No rotation, charge or other complexities and they are of equal mass. They move at near the speed of light towards each ...
- 11
3
votes
0
answers
258
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An equation satisfied by harmonic coordinates in a Schwarzschild spacetime
(Full disclosure, this is very much a "fish out of water" type situation: I'm working on something in an area very far away from the stuff I usually work with, so this is hopefully something ...
3
votes
0
answers
216
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Scattering cross-section in Curved space-time
Consider the following two definitions for differential cross-section $\sigma(\theta,\phi)$ that one often encounters in classical mechanics and in non-relativistic quantum mechanics:
$\textbf{...
- 1,752
3
votes
1
answer
228
views
In and out states of scattering in Asymptotically flat spacetimes
I am reading a paper called "New symmetries of massless QED", written by Temple He, Prahar Mitra, Achilleas P. Porfyriadis and Andrew Strominger (https://arxiv.org/abs/1407.3789). At some ...
- 3,992
2
votes
1
answer
90
views
Does frame dragging impart momentum?
Let's say a large object (think runaway planet) passed a much smaller one. The larger object's frame dragging distorts the space inhabited by the smaller object, so that it appears to briefly follow ...
- 719
0
votes
1
answer
122
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Black Hole S-Matrix
I am reading arXiv:2006.03606 where through Eq. (1.1) they say that the transition amplitude for collapse of matter from initial state $\Psi_{i}$ into a black hole and eventually evaporation of black ...
- 648
0
votes
1
answer
969
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Relation of specific angular momentum $h$ with velocity and impact parameter for massive particle?
I am computing the path of an incoming massive (!!) particle with speed $v$ far from the black hole in the schwarzchild metric. To determine its path, i need to input the specific angular momentum ...
7
votes
1
answer
1k
views
Feynman diagrams for gravity
Feynman rules are the basic tool to compute amplitudes in perturbation theory for a QFT. Here, I am trying to understand perturbation theory in GR around the flat space metric, in terms of Feynman ...
- 1,182
13
votes
1
answer
576
views
Will a black hole cause scattering of a gravitational wave?
In my GR textbook, it states that gravitational waves can undergo interference but not scattering.
I am just starting the chapter on linearised gravity concepts (weak field approximation) and my ...
user81619
5
votes
0
answers
299
views
Calculating forces via Feynman diagrams?
How would one go about calculating forces that test objects feel using Feynman diagram methods?
For example, say we have a massive object in GR so that the metric takes on the standard Schwarzschild ...
- 3,492