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I know from reading about the gravitational waves detected by Ligo, that when an object has angular acceleration, it produces gravitational waves.

I'm wondering if an object creates gravitational waves when only accelerating in one direction, however?

I'm also curious as to how the nature of the waves would differ in this case.

magma
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  • Do you know how to solve the problem for electromagnetic waves? What happens if you apply the same logic here? – CuriousOne May 18 '16 at 03:47
  • Objects don't just accelerate in one direction without having a violent force being applied to it, and the violent force itself will create gravitational waves. – Neil May 18 '16 at 08:37
  • Aren't all objects in a gravitational field being accelerated? Or at least the equivalent. For example on the surface of the earth, acceleration due to gravity is 9.8 meters per second squared. An object just sitting there is equivalent to being accelerated. Based on that theory wouldn't everything constantly produce gravitational waves? – Bill Alsept May 18 '16 at 16:01

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Any object with mass that accelerates (is it linear or angular acceleration) produces gravitational waves, though in most occasions those will be much too small to be detected. As @CuriousOne pointed out, same happens with electromagnetic waves and accelerating charges. The gravitational waves that can be detected usually come from very massive objects (such as black holes, neutron stars, etc) undergoing rapid accelerations. The situations encountered in nature where this really massive objects are accelerated tend to be related to binary stars or black hole systems orbiting each other or single stars swiftly rotating about their own axis with a noticeable irregularity like a mountain on their surface. I'd say the reason why you don't hear much about GW produced by linearly accelerating black holes/stars is that this scenario is quite unlikely to happen in nature.

You can find information about the other possible sources of GW here.

dahemar
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    Any object with mass that accelerates (is it linear or angular acceleration) produces gravitational waves, Not true. In general the condition required for gravitational radiation from a point mass is that $d^3x/dt^3\ne0$. –  Dec 16 '17 at 16:13
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    @BenCrowell, Rigorously you're correct, but I believe that here in "object" it's implicit "finite object", thus excluding point particles. That's the same language used in the LIGO webpage. – stafusa Dec 22 '17 at 18:10
  • A symmetric mass accelerated object does not radiate gravittional waves due to the quadrupole(not dipole as in EM) of radiation – anna v May 26 '21 at 10:51
  • WHY do accelerating bodies generate/radiate GWs, away? Why don't inertial ones, then? –  May 28 '21 at 12:42