Questions tagged [gravitational-waves]
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What is the difference between tidal bulge due to Earth & Moon on Sun Vs Binary black holes tidal bulge on Sun?
As the speed of these waves depends on their revolution speed, How Tidal bulge different than gravitational waves? For black holes, this revolution speed may be 299792458m/s.
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Do gravitational waves carry momentum?
We know from the idea of wave-particle duality that electromagnetic waves are photons which have the property of momentum. It stands to reason that gravitational waves would have similar duality. ...
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Do planets orbiting stars emit gravitational waves?
I have heard it said that charged planets could not orbit a massless (low mass) oppositely-charged star based on electromagnetic attraction the same way they can with gravitational attraction, because ...
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What is the typical order of magnitude (*numerical* in $\rm Hz$, not expression) of frequency of a gravitation wave? [duplicate]
What is the typical order of magnitude of frequency of a gravitation wave ?
I have read Frequency of gravitational waves
but they only give expression, without any quantitative numerical answer for ...
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Are the meaning of the two polarisations of gravitation wave arbitrary since one could choose arbitrary the axis direction?
Are the meaning of the two polarisations of gravitation wave arbitrary since one could choose arbitrary the axis direction ?
I write the same in a different way : what is the meaning of the two ...
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In which direction would gravitational waves be emitted when two black holes colide?
Imagine two black holes on the x-axis coming together at the origin (not rotating around each other, just falling towards each other).
In which direction would the most intense gravitational waves be ...
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How to calculate the likelihood PDF of gravitational wave data
I am trying to explore how gravitational wave (GW) data analysis works.
Background
The detector output in the time domain $s(t)$ is the linear combination of the true GW signal $h(t;\theta)$ ...
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Why do gravitational waves circularize a binary?
I understand that a binary orbiting around one another will circularize due to the emission of GWs due to Peters equations and that highly eccentric binaries evolve faster.
But GW emission also ...
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What would cause a gravitational wave that is measured on Earth by “macro-sized” instrumentation?
LIGO has successfully measured the effect of gravitational waves moving through the Earth from a very distant source. Such measurements require extremely precise and calibrated instrumentation ...
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How does LIGO cover the whole sky?
This article says that "[LIGO] is an omnidirectional gravitational-wave detector that monitors the entire sky."
But how is that possible with just two flat detectors? If both locations detect a wave ...
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What is the effective radius of stellar graviton emission?
White dwarfs have been used to accurately determine photon gravitational redshift:https://scholar.google.co.uk/scholar?as_ylo=2016&q=white+dwarf+gravitational+redshift&hl=en&as_sdt=0,5#d=...
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Is there a simple formula for the gravitational self-force (due to emission of gravitational waves) in the classical limit?
UPDATE: To clarify things in response to comments below, I want to reformulate my question in a very concise and abundantly clear form. Let's consider an object of a known mass M that moves under the ...
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“Gauge Freedom” in GR
When we derive the equations for propagating waves in GR, we have to make a gauge choice to get something unique. I understand that in electromagnetism, the gauge is not in general something ...
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Gravitational waves from collapsing rotating mass? [closed]
According to the Birkhoff’s theorem, a non-rotating mass does not radiate gravitational waves during a spherically symmetric collapse. There is, however, no equivalent of the Birkhoff’s theorem for a ...
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Do the gravitational wave moves the Ligo's mirror or the photon in the laser beam?
On NASA website there is an animation showing a signal is detected when the gravitational wave shifts the mirrors about, causing the laser to go out of phase. Do gravitational wave actually shifts the ...
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Was ever observed a black hole - neutron star merger?
I remember that a few months ago the news of a possible a black hole-neutron star merger detected with LIGO/VIRGO was diffused.
Was this discovery confirmed?
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Gravitational Wave - What is waving?
Two kinds of wave transmission are:
Light waves, where a substance (photon) travels as a wave.
An attached rope, like at the gym, that is "waved" up and down. Here, no substance travels to a new spot,...
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On Gravitational Waves
I need someone to double check my thinking as I'm not sure I full understand General Relativity (GR) relating to gravitational waves.
imagine on a line there are three bodies, first a test particle 1 ...
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Can Zeeman effect occurs in gravitational wave from binary blackhole-magnetar merger
I understand that Zeeman effect is behind the splitting of spectrum lines in an atom in strong magnetic field, I was wondering if such phenomenon could occur outside electromagnetic wave such as from ...
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Could 2 collided neutron stars partialy lose mass?
If two collided black holes lose a huge part of their masses before collision do a pair of neutron stars lose such quantity of mass and is the density of an astronomical body the cause of how much of ...
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Could a powerful gravitational wave tear apart an object?
Gravitational waves can temporarily squeeze the fabric of spacetime itself, and, given enough energy, this could cause a single object in the way to be squeezed with spacetime (that it is in) itself ...
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How do out of phase tell us the amplitude of gravitational wave?
When gravitational waves hit the 2 mirrors in LIGO and causes the signals to switch between in-phase and out-of-phase, it should only show the changes in frequency. What about the amplitude of the ...
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Are there GW spheres like photon spheres around a black hole?
I have read this question:
Are gravitational waves effected by the curvature of space time (gravitational lensing)?
Gravitational lensing of gravity
Can gravitational waves orbit a black hole?
...
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Do frame dragging carry energy away like gravitational wave?
Imagine 2 blackholes inspiral closer as they emits tremendous amount of energy as gravitational wave, now I tried to intuitively imagine a spaceship doing a flyby(gravity assist) near a spinning ...
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In what way does general relativity predict gravitational waves? [duplicate]
When people say that general relativity predicts gravitational waves, how so?
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Is it possible to produce gravitational waves in a very small space using some gas? If so, how?
From what I know, gravitational waves are produced when accelerated massive bodies move through space-time and create ripples in the gravitational fields throughout the space-time. This is significant ...
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Why inflation give rises to gravitational wave?
GR predicts accelerated expansion of spacetime should create gravitational wave, how? I thought universe does not have a center and the big bang happens everywhere so then where do these early ...
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Would relativistic LIGO hear different chirp?
Imagine a binary blackholes merger about 100 Mpc away and LIGO's relativistic twin is orbiting Earth at close to speed of light, I wonder would both LIGO and its twin show different results? For this ...
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Why does Light get caught by Gravity, when both are travelling at the Speed of Light?
Gravitational waves travel at the speed of light waves.
So then, why do light waves get caught by gravitational waves (eg, black holes)?
And if it is about the strength of the photon field, then why ...
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What is the reason gravitational waves propagate at speed of light? [duplicate]
I know Maxwell equation shows that it is the electric and magnetic properties of empty space which is why speed of light is constant, but what about gravitational waves? I have visited many answers ...
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What causes a black hole ringdown and why can it prove the no-hair theorem?
When two black holes merge, they will produce the so-called ringdown before forming a new black hole, even the newly created black hole produces some sort of tones due to the force of the impact, but ...
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Contribution of gravitational waves to a maximum-entropy big bang
Our universe did not have a maximum-entropy big bang. If it did, then by the second law of thermodynamics we wouldn't see the universe today in a non-equilibrium state. I've seen this explained by ...
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What is meant by GWs are self interacting (damping)?
I have read this question:
How do gravitational waves sustain and propagate large scale spacetime curvature?
where John Rennie says:
I think the analogy with the EM field is a good one with some ...
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How do gravitational waves carry energy/radiation? [duplicate]
How are gravitational waves related to gravitational radiation? How does gravitational radiation carry radiation/energy? What is it from?
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What is gravitational radiation?
What is gravitational radiation (in association with gravitational waves)? Is it a form of energy/mass? Or is it just another word for gravitational waves?
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Is there a way to detect gravitational waves in subatomic particles?
Consider the hypothetical situation of two electrons orbiting each other with a certain radius between them, going at extremely high speeds.
Would this create gravitational waves strong enough to be ...
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Do particles produce gravitational waves?
We have obviously detected gravitational waves at very large scales, but what about small scales? I accept the answer that they would be indetectable, however I would think it would, considering the ...
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A possible consequence of LIGO measurement of Gravitational Waves [duplicate]
LIGO measured Gravitational Waves.
Presuming here that the Gravitational Waves can be considered as a disturbance or change in a Gravitational Field, as described here on this Quora question:
What ...
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Do Gravitational Waves cause a 'Rate of change of Acceleration'?
I was reading the answers to a question regarding the difference between Gravitational Waves and Gravitational Field on Quora:
Quora Question: What is the difference between Gravitational Field and ...
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Can we tell how far away is the source of gravitational wave from the chirp alone? [duplicate]
From the analysis of chirp from Ligo and some other similar detector it is possible to tell the mass but can we also find out how far away too? or we need to look up into the sky and compare the ...
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What happens to the momentum when 2 black holes collide and no matter is present?
Imagine 2 non-spinning black holes with identical mass collides with each other at the same speed in the absence of other matter, I think the gravitational waves can only carry a little of the ...
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Can a charged (likely) binary black hole ( BBH) system be in a stable circular orbit (SCO)?
A BBH is a system consisting of two black holes in close orbit around each other.
The last stable orbit or innermost stable circular orbit (ISCO) is the innermost complete orbit before the ...
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What is meant by “gravity waves we see at sea surface”?
I've read in an answer to this question, of which I think that it was a very good, but somewhat long one, (I include the context in which it was written):
Let me expand this point. When this ...
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Is space time interval formula $ds^2=\eta_{\mu\nu}dx^\mu dx^\nu$ changed in presence of gravitational wave perturbation?
In relativity theory, in absence of any perturbation of the space time, we have conservation of spacetime interval :
$$ds^2=\eta_{\mu\nu}dx^\mu dx^\nu$$
where $\eta_{\mu\nu}$ is the Minkowski metric....
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Free fall and gravitational waves
If you take the Earth-Moon system, from what I understand, the Moon for instance is in free fall towards the Earth-Moon center of mass. However Einstein's equivalence principle says that a body in ...
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Can gravity be conceived of as 'repelling' regions of lower energy density?
*I'm a writer, not a physicist, so please bear with me in my 'ham'-handling of physics and its terminology!
My question is about whether repulsive forces over large distances could exist.
My ...
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How do we see an object fall into a Black hole in gravitational waves? [duplicate]
If an object emitting light falls into a black hole, the conventional wisdom is that an observer (at infinity) will never actually see it fall in - they will see it moving slower and slower as it ...
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SXS gravitational wave data question
I need to do some analysis for a project with the SXS gravitational wave data: https://data.black-holes.org/waveforms/catalog.html but I am a bit confused about the initial conditions of their ...
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Dirac Delta Function and Schwarzschild Singularity [duplicate]
Pardon my naive question. I recently found out about Dirac Delta function. It is interesting to note that Schwarzschild singularity gives the infinity values of the General relativity field equations ...
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An equation for derivation of gravitational waves polarization forms
When I was reading Spacetime and Geometry An Introduction to General Relativity by Sean Carroll(Page 297,Equation 7.110), I couldn't solve this problem in the proper way to get an approximation.
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