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Space-time and gravitational fields

I am reading a book by Carlo Rovelli, Seven Brief Lessons On Physics, and would like to check if I have understood something. Apologies if my question is badly phrased, feel free to edit where ...
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0answers
66 views

Gravitational waves: novel or confirmatory?

If the rumors are true and gravitational waves have been detected, would we learn any new fundamental physics from them? Or is this simply an important confirmation of a prediction of general ...
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2answers
112 views

Gravitational waves, tides and the end of universe

Is tides proof of gravitational waves with low frequency? According to Wikipedia, In physics, gravitational waves are ripples in the curvature of space-time which propagate as waves, travelling ...
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2answers
185 views

Gravitational waves and time

Two questions. It is said that time can only go slower in gravity fields and if you move faster. I have heard that when a gravitational wave pass earth then the space/time vibrate and time change ...
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3answers
73 views

Could the recent evidence of a gravitational force orbiting the solar system indicate not the existance of a ninth planet, but rather a black hole?

In case you haven't heard already, researches at the California Institute of Technology discovered mathematical evidence of large object orbiting the sun at a distance about 20 times further than that ...
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0answers
46 views

Can gravitational waves produce “sonic boom”?

I've heard that a fast moving object such as a jet plane traveling much faster than speed of sound can produce shockwaves which is also known as sonic boom, also Cherenkov radiation is produce by ...
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0answers
45 views

Gravitational wave as a consequence of gravity being a field

I was reading an online article about gravitational wave detection and there is a sentence which says: The existence of gravitational wave is simply a consequence of the fact that gravity is a ...
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1answer
59 views

What are the benefits of Gravitational wave studies?

Gravitational waves were first predicted by Albert Einstein and later indirectly confirmed in an number of experiments. Recently leading physicists announced that they may have a 'solid' proof that ...
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0answers
47 views

How gravitational waves are exactly produced?

I was thinking about gravitational waves, and I found out that I may have a doubt about their production. Assuming the whole calculations find a wave-like solution to be understood, I was wondering ...
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2answers
198 views

The ADM Energy of Gravitational Waves?

I have been looking for books about this question for several days. However, almost all books use Landau–Lifshitz pseudotensor to calculate the energy of Gravitational Waves.And they said the result ...
3
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1answer
76 views

Isn't LIGO basically measuring the luminiferous aether?

I am bit confused about this one. I am not very acknowledgeable about gravitational waves and LIGO. But if it is basically a Michelson interferometer and can detect shifts in vacuum, doesn't this ...
3
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1answer
124 views

Why are nonrelativistic methods used in binary pulsar systems (gravitational waves)?

Although gravitational waves are a subject of the General Relativity, why do most books use Newtonian equations of motion for power radiated and rate of change of eccentricity calculations? In most ...
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1answer
325 views

Would warp bubbles emit gravitational Cerenkov radiation in general relativity?

Inspired by the gravtiomagnetic analogy, I would expect that just as a charged tachyon would emit normal (electromagetic) Cerenkov radiation, any mass-carrying warp drive would emit gravitational ...
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3answers
148 views

What would be the implications for current theories if gravitational waves are not detected?

Let's assume that scientists trying to detect gravitational waves get a huge raise in funding, design even better experiments, and run them for decades, but just can't find any gravitational waves ...
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1answer
355 views

Simple quadrupole field not yet in Lorenz gauge?

I'm having trouble reproducing some of the results regarding gravitational waves in the Wald's General Relativity. In section 4.4 of gravitational radiation, eq.4.4.49 shows the far-field generated ...
3
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1answer
181 views

Unbounded perturbed geometry due to analiticity

I have an interesting mystery for you, loosely inspired on work related with this question. I have a certain Ansatz for a gravitational wave perturbation of the metric $h_{\mu \nu}$ that is nonzero ...
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1answer
366 views

Are there weak force waves?

In the same way as there are electromagnetic and gravitational waves that update the information on their respective field, is there an analogue for the weak and strong forces?
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0answers
51 views

Transforming to the Transverse-Traceless gauge

I have a certain Ansatz for a gravitational wave perturbation of the metric $h_{\mu \nu}$ that is nonzero in a compact set of background flat Minkowski spacetime But the Ansatz field does not satisfy ...
8
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2answers
751 views

Do gravitational waves slow down as they pass through matter?

I've heard that gravitational waves travel at the speed of light, and have some parallels to electromagnetic waves. EM waves slow down as they pass through matter (speed of light in glass is slower ...
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1answer
658 views

The final parsec “problem”

Many and perhaps all galaxies seem to contain supermassive black holes of about $10^7 M_\odot$ at their centres. Determining their origins is of great astrophysical interest. In what I understand to ...
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3answers
520 views

Do gravitational waves cause time dilatation?

The effect of gravitational waves in transverse traceless gauge on matter is represented by the expansion and contraction of a ring of test particles in the direction of polarization of the wave. ...
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1answer
35 views

Why only binary star system produce ripples in space-time (gravitational waves)?

I saw a statement being made in a video, but it didn't explain why. It originally said, "stars orbiting each other does not create gravitational waves, binary system of two massive stars or black hole ...
3
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1answer
424 views

Are some gravitational wavelengths forbidden by causality?

Consider a gravitational wave in linearized gravity $d_{\mu \nu}(X_{\eta}) = D_{\mu \nu} e^{i X_{\eta} K^{\eta}}$ with $K^{\eta} = (-\omega t, \textbf{k})$. Let $d=| \textbf{D}|$ the scalar maximum ...
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1answer
98 views

Gravity amplifier

Just a hypothetical question. Is it possible to increase or amplify gravitational interactions between two or more bodies ( without changing the mass)? Will changing the graviton ...
3
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3answers
250 views

Do gravitational waves exist at the quantum level?

Do gravitational waves exist at quantum level produced by electrons or by atoms or by molecules? If yes, which particle produces them and how are they produced? Spacetime exists at a quantum level ...
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1answer
133 views

What is the difference between gravitons and gravitational waves?

What is the difference between gravitons and gravitational waves? So as I understand, gravitational waves are predicted by and part of the theory of general relativity, whereas gravitons are predicted ...
2
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1answer
110 views

Does the Michelson-Morley experiment disprove gravitational waves?

I may be misunderstanding gravitational waves, but doesn't the idea of a gravitational wave imply that spacetime is a field or "medium" through which waves propagate at speed $c$? Was not this idea ...
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1answer
54 views

Evidence of possible tidal effects close to a gravitational wave emitting system

Currently we are attempting to detect gravitational wave emissions using the LIGO gravitational wave detection system (and similiar systems), by attempting to detect very weak gravitational waves ...
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0answers
17 views

Higher dimensional trapped surface and its condition?

In higher D-dimensional spacetime, a marginally trapped surface is a closed spacelike (D-2)-surface whose outer null normals have zero convergence. It is very like a marginally trapped surface in the ...
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1answer
40 views

Could an Alcubierre Drive modify a gravitational field? [closed]

I'm a high school student, so I have no clue if warping spacetime has any effect on gravitational fields, but the two seemed to be linked based on what I've watched and read. And if a warp drive is ...
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0answers
41 views

Is it true that GR waves can interfere if and only if the change to the metric can take negative values?

This appears to be a unique question compared to other topics about electromagnetic waves or quantum mechanics already on Stack Exchange. The topic on resonance doesn't really answer this question. ...
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0answers
17 views

objects and particles react to wave

Is it possible for a wave to be have a wavelength so small that it doesn't interact/affect an object? Like if it is smaller than the atoms itself will it still affect them? I am talking about a wave ...
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1answer
109 views

Can stress energy tensor vanish in general relativity?

When I saw the questions why matter-anti matter annihilation produces photons not gravitons, it suddenly occured to me that if the latter really happens, it means the stress energy tensor vanishes ...
8
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3answers
771 views

Is it possible to produce gravitational waves artificially?

Why don't they make a ball with irregularities, say the size of a tennis ball, then spin it very rapidly, so it would produce gravitational waves like a spinning star with irregularities on it? Is ...
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0answers
39 views

Can very strong gravitational wave collapse into a black hole? [duplicate]

Can a beam of very focused gravitational wave collapse into a black hole as ordinary matter(particle or radiation) does? Alternative question: can a black hole grow by absorbing gravitational wave ...
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4answers
2k views

Magnetic fields and gravitational waves. How far do they reach?

I read that magnetic fields perpendicular to a current shoot out and expand all the way to infinity. Additionally a gravitational wave, no matter how small will also expand to infinity at the velocity ...
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1answer
118 views

Does getting hit by a gravitational wave hurt? [duplicate]

Recently a paper in Nature about 2 black holes PG 1302-102 merging and causing a supernova 100 million times more powerful than common ones got me thinking. How much damage do gravitational waves do ...
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1answer
257 views

Can gravitational waves orbit each other to form a standing wave?

Since gravitational waves are a type of propagation of energy of some sort, they ought to induce their own gravitational field. I'm assuming this extra gravitational force / curvature is independent ...
6
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1answer
194 views

How close would you have to be to the merger of two black holes, for the effects of gravitational waves to be detected without instruments?

Assume two black holes in the most common size range, spiraling into each other until they merge. The event releases significant amounts of energy via gravitational waves, which warp the space-time. ...
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2answers
89 views

Gravitational waves in general relativity

After reading some concepts of general relativity,is it true that the universe communicate with its different constituents (stars, galaxies, etc...) via gravitational wave? If so, how is that? Do ...
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1answer
187 views

Do gravitational lenses work on gravitational waves?

Do gravitational lenses work on gravitational waves? Could we get an Einstein cross of gravity?
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2answers
229 views

Has the speed of gravity been measured experimentally? How? [duplicate]

In Newtonian physics, changes in gravity propagate instantly. In general and special relativity, gravity propagates at the speed of light, $c$. From reading answers to questions about gravity on this ...
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4answers
209 views

How do gravitational waves work without internal tension?

One implication of general relativity is the concept of gravitational waves or gravitational radiation, ripples in spacetime thought to travel at speeds close to the speed of light. As far as I have ...
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0answers
131 views

Can we create graviton particle or gravitational wave? [duplicate]

Can we create graviton particle or gravitational wave? I want to know if we able to generate graviton particle out of some energy. Is it theoretically possible? And could we generate gravitational ...
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4answers
2k views

Trying to understand what a gravitational wave is

It seems to me that there is a great deal of interest in the possibility of gravitational waves. Several gravitational-wave detectors have been built, and there is even a branch of science with that ...
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2answers
587 views

Monopole Gravitational waves exist?

GR says that monopole gravitational radiation does not exist. I understand the reasons for this. However there is this effect (which seems to me to have the hallmarks of a wave). Paper at arXiv: ...
3
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1answer
184 views

Does all matter emit gravitational waves all the time?

I understand that gravitational force is a result of the curvature of spacetime and that the analogy with electromagnetic waves falls apart at a certain point. However, I have been confused when ...
0
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2answers
59 views

What can gravitational wave tells us about space?

If we can detect gravitational waves (if it exists) is it going to explain why the force of gravity is so much weaker compared to other fundamental forces or is it able to tell us why stuffs with mass ...
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1answer
70 views

Could it ever be possible to generate small gravitational waves?

Would it ever be possible to make a device that could generate small,short gravitational waves? If so, it would then be possible to use artificial gravitation for space travel. Assuming that gravity ...