What is Gravitational waves: Definition and 330 Discussions

Gravitational waves are disturbances in the curvature of spacetime, generated by accelerated masses, that propagate as waves outward from their source at the speed of light. They were proposed by Henri Poincaré in 1905 and subsequently predicted in 1916 by Albert Einstein on the basis of his general theory of relativity. Gravitational waves transport energy as gravitational radiation, a form of radiant energy similar to electromagnetic radiation. Newton's law of universal gravitation, part of classical mechanics, does not provide for their existence, since that law is predicated on the assumption that physical interactions propagate instantaneously (at infinite speed) – showing one of the ways the methods of classical physics are unable to explain phenomena associated with relativity.
The first indirect evidence for the existence of gravitational waves came from the observed orbital decay of the Hulse–Taylor binary pulsar, which matched the decay predicted by general relativity as energy is lost to gravitational radiation. In 1993, Russell A. Hulse and Joseph Hooton Taylor Jr. received the Nobel Prize in Physics for this discovery. The first direct observation of gravitational waves was not made until 2015, when a signal generated by the merger of two black holes was received by the LIGO gravitational wave detectors in Livingston and in Hanford. The 2017 Nobel Prize in Physics was subsequently awarded to Rainer Weiss, Kip Thorne and Barry Barish for their role in the direct detection of gravitational waves.
In gravitational-wave astronomy, observations of gravitational waves are used to infer data about the sources of gravitational waves. Sources that can be studied this way include binary star systems composed of white dwarfs, neutron stars, and black holes; and events such as supernovae, and the formation of the early universe shortly after the Big Bang.

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  1. S

    I What happens to gravitational waves?

    Two black holes that are orbiting and collide give off mass in the form of gravitational waves before the collision. Do these waves get absorbed by something, or is this mass lost to the universe?
  2. K

    I Gravitational Waves: Prerequisites for Study

    I am interested in studying at least the basics of gravitational waves. How much knowledge do I need to have about waves in general before procceding?
  3. .Scott

    I Gravitational Waves: Questions on Mass & Escape Velocity

    A few years go, we detected a gravity chirp from the collapse of binary black holes. The initial total mass was about 21.7 solar masses. The end result was about 20.8 solar masses. The difference was presumably contained in the gravity wave. I believe, under the right conditions, an object...
  4. P

    I Gravitational Waves & Matter: Causes, Effects & Thresholds

    From what I have read gravitational waves are caused by the acceleration of massive object causing ripples in space time. What specifically causes this, and how does general relativity predict these. Does it have to be a high density of matter, or a large amount of it. How do these waves affect...
  5. cianfa72

    I Can Gravitational Waves Affect Light Wavelengths?

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  6. C

    I Detect Negative Mass Matter: Experiments in Solar System

    How could we detect negative mass matter? The only proposal I've ever heard of is that we could detect there's a cutoff frequency in the gravitational waves we receive, due to attenuation of those lower frequency waves by negative matter. Are there more experiments that could be conducted...
  7. alan123hk

    B Gravitational waves for data communication?

    When and how can the gravitational wave be used for data communication, which the speed be much faster than the current technology by means of electromagnetic wave like 5G, 6G..etc wireless systems ?
  8. Y

    B Gravitational waves of moving or vibrating masses

    I am curious if the motion of massive object can effect it's gravitational influence due to the fact that gravitational waves travel at the speed of light. For a weak analogy, consider how a small object can make bigger ripples in the water if it is moving around more. I am curious if there...
  9. astroman707

    Physics Is gravitational wave research a smart direction to go in?

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  10. Kaustubh Namjoshi

    I Gravitational waves and the multiverse

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  11. Ebanflo

    I Is any attention being given to Conformal Cyclic Cosmology?

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  12. l0st

    I Gravitational Waves Cause Uniform Space Expansion: Exploring MNRAS Papers

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  13. T

    B Neutron Star Collisions: Creation of Heavy Elements and Their Fate

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  14. B

    B Gravitational waves and refraction patterns....

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  15. Islam Hassan

    I Gravitational Waves vs Gravitons

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  16. yerty4235437y

    B Could Gravitational Waves Allow for Time Travel?

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  17. negative

    B Black Hole Paradox: Exploring Gravity Waves

    well since gravity waves are supposed to have mass, they are supposed to be effected by gravity itself, and :/ how are we supposed to detect gravitational waves emitted from a black hole when none can get out?
  18. J

    I Max Amplitude Gravitational Waves: 2?

    I am curious as to what the maximum amplitude of gravitational waves is. I have read that the maximum amplitude as such is equal to two but I cannot seem to find again a reference that states this clearly.
  19. alantheastronomer

    A Gravitational Waves: Expansion of Spacetime?

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  20. Andrew Washington

    B LIGO Observation of Gravitational Waves: Questions Answered

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  21. BlackholeGirl

    I [Question] Tell me the latest catching news about black holes

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  22. arupel

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  23. H

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  24. P

    Exploring the Surface of a Black Hole's Event Horizon

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  25. S

    I Gravitational Waves vs Universe Expansion Rate

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  26. V

    I Gravitational Waves Affecting EM Fields: Evidence & Implications

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  27. L

    B Implications of gravitational waves from the Big Bang?

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  28. N

    B How to measure Gravitational waves

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  29. R

    B Do Objects in Motion Create Gravitational Waves?

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  30. A

    B How does LIGO measure gravitational waves

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  31. Auto-Didact

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  32. jerromyjon

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  33. F

    I Can two gravitational waves orbit each other?

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  34. S

    I Is the speed of gravitational waves non- dispersive?

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  35. nmsurobert

    B Are Gravitational Waves accepted?

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  36. Auto-Didact

    A Erebons: Planck mass Dark Matter particles

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  37. K

    B Can gravitational waves interfere with each other?

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  38. mfb

    I Virgo joins the measurement of gravitational waves

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  39. A

    A Speed of Gravitational Waves confirmed by Experiment?

    It seems that with the 2016 LIGO and VIRGO confirmation of the gravitational chirp that we have also experimental confirmation that the speed is indeed the speed of light. True? https://en.wikipedia.org/wiki/First_observation_of_gravitational_waves#Direct_observation
  40. Auto-Didact

    A Penrose: Noise in LIGO signal implies CCC

    Roger Penrose, July 2017. Correlated "noise" in LIGO gravitational wave signals: an implication of Conformal Cyclic Cosmology
  41. Buzz Bloom

    I What is the nature of the force causing deviation from a circular orbit in GR?

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  42. N

    B Gravitational Waves: Mass Interaction Questions Answered

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  43. A

    I Gravitational Waves Impact Earth's Orbit: Effects & Possibilities

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  44. Paul Colby

    I Are Evanescent Gravitational Waves Measurable

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  45. K

    I Signatures of extra dimensions in gravitational waves

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  46. E

    How Does LIGO Detect Gravitational Waves Using Laser Interferometry?

    Homework Statement In-phase light from a laser with an effective power of 2x105J and a wavelength of 1064nm is sent down perpendicular 4km arms of the LIGO detector. (i) Determine the number of photons traveling in the interferometer arms. (ii) Assuming the detector is sensitive enough to...
  47. RyuuJin

    A Gravitational waves: effect of frequency on strain

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  48. needved

    A Help to understand the derivation of the solution of this equation

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  49. hsdrop

    B Gravitational Waves as Transportation | Space Travel

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  50. A

    B Transmitting information using gravitational waves

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