Questions tagged [gravitational-waves]
For questions about the propagation of waves carried by space-time, for instance as described by general relativity. Not to be confused with gravity waves, such as ocean surface waves.
1,274 questions
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Why does LIGO use an IR laser?
The phase difference at the beam splitter of a LIGO-like interferometer is given by
$$ \Delta \phi \simeq \frac{4\pi}{\lambda} h L\ , $$
where $h$ is the gravitational wave strain (assuming a ...
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Extending topological phase singularity analysis to linearized gravity: superluminal nulls?
This question was prompted by Bucher et al. published in Nature last month:
Bucher T. et al. “Superluminal correlations in ensembles of optical phase singularities.” Nature, Vol. 651, pp. 920–926, ...
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Energy spectrum of a gravitational wave from a binary system
I am busy studying Gravitational waves and have come across two definition which I am not entirely certain off how they are derived and what they mathematically represent.
The first is the energy ...
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How do gravitational waves propagate through spacetime without a medium? [duplicate]
How do gravitational waves propagate through spacetime without a medium?
I'm trying to understand gravitational waves at an introductory level, and I'm confused about how they propagate.
My confusion:
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Can you suggest any resources that explain gravitational waves easily?
can you suggest any resources that explain gravitational waves easily?
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Gravitational Waves to sound
I'm currently in my second bachelor of mathematics (with extra physics). I want to make mp3-files or wav-files from real observations of gravitational waves for a personal little project. (In the best ...
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Could massless solitons exist in general relativity?
Solitons are an unusual type of waves which don’t disperse due to nonlinear effects. Since general relativity is nonlinear, we can expect the existence of soliton gravitational waves or EM waves. ...
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Bounce Solution for the Transition rate in 1D Quantum Mechanics
I am trying to derive equation (3.13) from this article on 1st Order Cosmic Phase transition and GWs. First, they are calculating the transition rate $\langle q_0| e^{-i H (t_f-t_i)}| q_0\rangle$ in ...
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What is the modern resolution to 1977 Rosen "Does gravitational radiation exist?" advanced waves issue?
Half a century ago Nathan Rosen questioned existence of gravitational waves claiming they should emit 1/2-1/2 retarded-advanced waves: https://link.springer.com/article/10.1007/BF00759493
In 1991 Huw ...
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What determines the stability of a Kerr black hole under perturbations?
Does anybody know what factors influence the stability of a Kerr black hole when small perturbations are applied? While I know the Kerr–Newman solution is generally considered to be linearly stable, I ...
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Time-averaged energy flux of a wave?
In the context of linearized General Relativity, if a monochromatic, plane-fronted gravitational wave in the transverse-traceless (TT) gauge is described by the metric perturbation:
$
h_{ij}^{\mathrm{...
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Perturbative Expansion in the Vielbein Formalism
Most of perturbation theory in GR is done by perturbing the metric, i.e. writing $g = g_B + \alpha h$, where $\alpha$ is our expansion parameter and $h$ is our perturbation, and then developing either ...
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Incomplete treatment in Sean Carroll’s GR notes, of phase and wave vector?
I am studying linearized gravity and the construction of the transverse–traceless (TT) gauge starting from the Lorenz gauge, pages 149/150 of Sean Carroll’s GR notes, linked below.
After imposing the ...
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Gravitational stress energy tensor conservation $\partial^a t_{ab} = 0$
In the context of the linearized Einstein equations and gravitational waves, Wald defines an effective "stress-energy tensor of the gravitational field" which is constructed from quadratic ...
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Gauge transformation in GR and wave vector
When we perform a gauge transformation in GR, is it just a coordinate transformation? Or is it something deeper? Because in the derivation of gravitational waves, we first went to Lorenz gauge and ...
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