Tout Ou Dwe Konnen sou Lanm gravitasyonèl

Everything You Need to Know about Gravitational Waves

Nan mitan rimè kap kouri ke yon Obsèvatwa US pral anonse nan Jedi ke yo te detekte prèv nan vag gravitasyonèl, isit la nan enfòmasyon an kle


Powered by Guardian.co.ukAtik sa a ki gen tit “Gade spacetime sa a: gravitasyonèl vag dekouvèt atann” te ekri pa Ian Egzanp editè Syans, pou gadyen legal la nan Madi 9yèm fevriye 2016 15.59 UTC

Yon deseni-long rechèch pou vag gravitasyonèl espere fini nan triyonf semèn sa a lè syantis, yo deklare yo yo te dekouvri rid nan twal la nan spacetime, pètèt kreye pa kolizyon an nan de twou masiv nwa vwayaje nan fèmen nan vitès la nan limyè.

Premye prevwa pa Einstein, ak ki te pwodwi pa evènman ki pi kataklismik nan Cosmos yo, vag gravitasyonèl detire ak espas boulon ak tout nan li menm jan yo gaye soti toupatou nan linivè la. dekouvèt yo, si konfime, se sèten yo resevwa yon pri Nobèl.

Syantis yo te chase pou siy nan vag yo pou dè dekad, men jouk kounye a, tantativ yo yo te fristre pa siyal fo ak enstriman mizik yo pa t 'sansib ase yo detekte vag yo pa tan an yo rive jwenn Latè.

Yo prevwa ki ka chanje nan Jedi, lè fizisyen nan peyi Etazini an revele done dènye yo soti nan yon eksperyans li te ye tankou LIGO, oswa Obsèvatwa a avanse Lazè entèrferomètr gravitasyonèl-Vag. Ekip la gen detektè nan Washington ak Louisiana ki ka tach pase vag gravitasyonèl atravè chanjman sa yo enfim nan longè yo pwodwi nan de tiyo 4km-long.

Nan yon konferans pou laprès nan Washington, LIGO syantis yo antisipe revele yon klè, ékivok gravitasyonèl siyal vag. Li ka te soti nan de twou vas nwa, youn 29 fwa plis masiv pase solèy la, lot yo 36 fwa plis masiv, espiral alantou youn ak lòt epi finalman ekraze ansanm yo fòme yon nouvo twou nwa 62 fwa mas la nan solèy la. Pou tout HEFT li yo, kò a nouvo pouvwa gen pa plis pase 200 mil lajè.

Mas la manke – ekivalan a sa yo ki an twa solèy, oswa sis billions billions kiloton – te konvèti nan enèji ak lage kòm vag yo gravitasyonèl LIGO se te kwè ki te detekte.

"Moun yo lajman eksite. rimè a se ke li nan yon kolosal siyal gwo, nan lòt mo, li nan ékivok, e ke se kokenn,"Te di Pedro Ferreira, pwofesè nan Astwofizik nan Oxford University, ak otè de la 2014 liv, Pafè Teyori a: yon syèk nan jeni ak batay la sou relativite jeneral.

Lè Einstein pibliye teyori li nan Relativity jeneral nan 1915, li chanje pou tout tan ki jan syantis wè linivè a. Teyori a te montre ke mas fè spacetime koub, yon efè ki gen yon foul moun nan enplikasyon. youn, ki limyè ki soti nan zetwal byen lwen ap pliye ozalantou Solèy la, te konfime pa Arthur Eddington pandan eklips solè a nan 1919.

deteksyon an nan vag gravitasyonèl ta tik sou dènye prediksyon nan pi gwo nan relativite jeneral. Li ta demontre ke ekwasyon yo trase moute pa Einstein, ki te refize kwè nan twou nwa tèt li, kenbe vre nan sa ki Hang kòm domèn nan pi ekstrèm nan fizik.

Men, gen plis nan dekouvèt la nan vag gravitasyonèl ke tou senpleman pwouve yo egziste. Si siyal la LIGO se osi fò ke rimè kap kouri sijere, enstriman mizik nouvo ta ka bati yo detekte vag gravite soti nan fè kolizyon twou nwa ak lòt evènman lajman enèjik tout lòt peyi sou linivè la.

"Li ta tankou gen yon teleskòp ki, olye pou yo gade nan objè ki nan spectre an elektwomayetik, se kap nan yo ak vag gravitasyonèl,"Te di Ferreira. "Nou te kapab wè bagay sa yo nan yon fason konplètman diferan. Li ta dwe trè trouble vizyon – vag gravitasyonèl yo pa bon nan pinpointing objè – men yo ta ka ede nou konprann sa ki pase lè twou nwa hs tonbe nan youn ak lòt. "

"Reyalite a se chak fwa nou te gade linivè a nan nouvo fason, ak radyografi, ak onn radyo, nou te dekouvri bagay enkwayab, ègzotik. Se konsa, sa a ki pral louvri moute yon lòt fenèt, ak pou asire w nou pral dekouvri ra bagay,"Li te ajoute.

Rumours that the LIGO team had detected gravitational waves have been circulating in the astrophysics community for months. Men, many researchers were sceptical and feared the rumours might have been sparked by synthetic signals which are added to the data to test the team’s analytical procedures.

“After all the rumours over the past few months I certainly expect them to announce a detection at this point,” said Alberto Sesana, a researcher at the University of Birmingham’s Gravitational Wave Group. “We have to bear in mind that LIGO is one experiment and the only one that can detect such sources. If they claim to have detected gravitational waves, it cannot be confirmed by another instrument, and that is always an issue. But they have been very cautious in doing this properly. I’m confident they have clear and strong evidence for it.”

There is a chance a signal will be announced from another source, such as a pair of neutron stars spinning around one another, or a neutron star falling into a black hole. But such cosmic events would be expected to produce weaker signals than the large spike scientists anticipate the LIGO team to reveal.

Scientists have declared the discovery of gravitational waves before only to have their hopes dashed. Nan 2014, researchers on an experiment called Bicep2 claimed to have found evidence for gravitational waves from the big bang, but further analysis by other groups showed that the signals they picked up could be entirely explained by space dust interfering with their measurements.

Ulrich Sperhake, a theorist at Cambridge University who studies how gravitational waves are generated by black holes, said the community was very excited and expectant. “ I don’t know anyone in the field who expects anything other than a detection to be announced,"Li te di. “Anything but the onset of a new era in observational gravitational astronomy would come as a major surprise on Thursday, but there remains a tiny speculative element to it until we’ll have the official LIGO announcement.”

Martin Hendry, a member of the LIGO team at Glasgow University, would not be drawn on the details of Thursday’s announcement. “I can’t say anything more at this stage than wait and see. Or should that be “watch this spacetime?"Li te di.

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