Gravitational wave

Gravitational waves are oscillations of the <a href="/facts/Gravitational_field/K1uTmJFy">gravitational field</a> that <a href="/facts/Wave_propagation/PXhWIt7k">travel</a> through space at the <a href="/facts/Speed_of_light/sKSQwdNx">speed of light</a>; they are generated by the relative motion of <a href="/facts/Gravity/bqAN7DdQ">gravitating</a> masses. They were proposed by <a href="/facts/Oliver_Heaviside/ktYBpAt7">Oliver Heaviside</a> in 1893 and then later by <a href="/facts/Henri_Poincar%25C3%25A9/AazL2j4X">Henri Poincaré</a> in 1905 as the gravitational equivalent of <a href="/facts/Electromagnetic_radiation/Ynx7ujCW">electromagnetic waves</a>. In 1916, <a href="/facts/Albert_Einstein/CNTet8qu">Albert Einstein</a> demonstrated that gravitational waves result from his <a href="/facts/General_theory_of_relativity/jVsoIg8X">general theory of relativity</a> as ripples in <a href="/facts/Spacetime/uRIN1x4b">spacetime</a>.
Gravitational waves transport energy as gravitational radiation, a form of <a href="/facts/Radiant_energy/8QHpm6KY">radiant energy</a> similar to <a href="/facts/Electromagnetic_radiation/Ynx7ujCW">electromagnetic radiation</a>. <a href="/facts/Newton%2527s_law_of_universal_gravitation/F6qH2XC3">Newton's law of universal gravitation</a>, part of <a href="/facts/Classical_mechanics/ykG8upsN">classical mechanics</a>, does not provide for their existence, instead asserting that gravity has instantaneous effect everywhere. Gravitational waves therefore stand as an important relativistic phenomenon that is absent from Newtonian physics.
<a href="/facts/Gravitational-wave_astronomy/eJGxCvdl">Gravitational-wave astronomy</a> has the advantage that, unlike electromagnetic radiation, gravitational waves are not affected by intervening matter. Sources that can be studied this way include <a href="/facts/Binary_star/TYlDe1bD">binary star</a> systems composed of <a href="/facts/White_dwarf/gIYlTtrC">white dwarfs</a>, <a href="/facts/Neutron_star/4enfoxBA">neutron stars</a>, and <a href="/facts/Black_hole/1r2lmkcF">black holes</a>; events such as <a href="/facts/Supernova/Pfo2J23l">supernovae</a>; and the formation of the <a href="/facts/Chronology_of_the_universe/ezBKAdjy">early universe</a> shortly after the <a href="/facts/Big_Bang/I5T1vTnv">Big Bang</a>.
The first indirect evidence for the existence of gravitational waves came in 1974 from the observed orbital decay of the <a href="/facts/Hulse%25E2%2580%2593Taylor_pulsar/GMTAbnBj">Hulse–Taylor binary pulsar</a>, which matched the decay predicted by general relativity for energy lost to gravitational radiation. In 1993, <a href="/facts/Russell_Alan_Hulse/g8lTxvu9">Russell Alan Hulse</a> and <a href="/facts/Joseph_Hooton_Taylor_Jr./Dn44wNWD">Joseph Hooton Taylor Jr.</a> received the <a href="/facts/Nobel_Prize_in_Physics/o6w1nCbr">Nobel Prize in Physics</a> for this discovery.
The first <a href="/facts/First_observation_of_gravitational_waves/7yep4aM0">direct observation of gravitational waves</a> was made in September 2015, when a signal generated by the merger of two black holes was received by the <a href="/facts/LIGO/jX6jyJzM">LIGO</a> <a href="/facts/Gravitational_wave_detector/5PaoAqBg">gravitational wave detectors</a> in Livingston, Louisiana, and in Hanford, Washington. The 2017 Nobel Prize in Physics was subsequently awarded to <a href="/facts/Rainer_Weiss/LD6X2WoK">Rainer Weiss</a>, <a href="/facts/Kip_Thorne/o6wkjTtP">Kip Thorne</a> and <a href="/facts/Barry_Barish/ISj0Aajt">Barry Barish</a> for their role in the direct detection of gravitational waves.

Gravitational wave open-in-new

Gravitational wave