![]() But because the distortions they create in space-time are so minute, they weren’t detected until eight years ago. ![]() Scientists predicted the existence of these ripples, called gravitational waves, as far back as the 1910s. Just like snapping a bedsheet, if you move enough matter around fast enough, a wave of distorted space-time will ripple outward into the universe. Because space-time is flexible, you can make it wave. In general relativity, matter makes space-time bend, and space-time, in turn, guides how unconstrained matter will move. For Einstein, space and time were a single entity, “space-time,” comprising a flexible fabric that could be stretched and compressed, bent and warped. More than 100 years ago, Einstein introduced his radical general theory of relativity. Scientists had been awaiting such a discovery for decades. If the result bears up as more data are gathered, it’s a discovery that promises to open new windows on everything from the evolution of galaxies to the origin of the universe. That’s the takeaway from yesterday’s remarkable announcement that scientists have detected a “cosmic background” of ripples in the structure of space and time. Every star, every planet, every continent, every building, every person is vibrating along to the slow cosmic beat. Actually, the whole universe is Mongolian throat singing. "It was an enormous effort to reach the sensitivity to build a detector which could actually observe such tiny, tiny distortions.The whole universe is humming. "In the early days, it was not clear if these gravitational waves were real or could be observed," Ingelman told reporters here by video. The ripples were also detected by another instrument called VIRGO, near Pisa, Italy. Just last week, LIGO scientists announced they had detected gravitational waves for the fourth time, on Aug. The LIGO team has made several additional discoveries. (The LIGO detection was published in February 2016.) According to the rules of the committee, the discovery has to be published the year before the awards are announced. But Gunnar Ingelman, Secretary of the Nobel Committee and a professor of subatomic physics at Uppsala University in Sweden, said the detection of gravitational waves was not eligible last year. Some had expected the LIGO team to win the prize last year. He noted that it took more than 40 years for the discovery of antimatter to be used in positron emission tomography, or PET, scans common in hospitals today. The findings might seem esoteric, but Heuer said that it's difficult to predict when and in which field this research could have practical applications. He added that the detection of gravitational waves opens "a window into an unseen world that will bring us more information in the future about the universe." "I had really hoped for it because it's a fantastic discovery," DPG President Rolf-Dieter Heuer told Live Science. Scientists here at the German Physical Society (DPG) cheered the results. "Without them the discovery would not have happened," Nils Mårtensson, the chairman of the Nobel Committee for Physics, said of the three winners during a news conference in Stockholm. But, according to the Nobel rules, the prize can be shared by no more than three scientists. The paper announcing the September 2015 detection had more than 1,000 authors. The Nobel Committee acknowledged that the discovery was a huge collaborative effort. "It took thousands of people to come to this. "You have first to keep all the distortions out and then to increase the sensitivity of the measurement system," Winkler, who has worked on gravitational wave detection since the 1970s, told Live Science. But the changes are tiny - as tiny as one-thousandth of a diameter of a nucleon, said Walter Winkler, a physicist with the Max Planck Institute for Gravitational Physics in Hannover, Germany. If a gravitational wave passes through Earth, the laser in one arm of the detector will be compressed and the other will expand. The L-shaped LIGO detectors have two arms, each 2.48 miles (4 kilometers) long, with identical laser beams inside. It took scientists such a long time to arrive at the discovery because gravitational waves - even though they come from violent, powerful collisions - are extremely small once they reach Earth.ĭuring the event detected in September 2015, scientists think that about three times the mass of the sun was transformed into gravitational waves in less than a second.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |