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बेसिक इंग्लिश का दूसरा सत्र (कक्षा प्रारंभ : 22 अक्तूबर, शाम 3:30 से 5:30)
Gravitational Waves: A Breakthrough Discovery
Feb 20, 2016

A team of scientists recently announced that they had heard and recorded the sound of two black holes colliding a billion light-years away, a fleeting chirp that fulfilled the last prediction of Einstein’s general theory of relativity. One of the LIGO scientists said, this will be one of the major breakthroughs in physics for a long time. Finally, astronomy grew ears. We never had ears before.

  • The faint rising tone is the first direct evidence of gravitational waves, the ripples in the fabric of space-time that Einstein predicted a century ago.

  • It completes his vision of a universe in which space and time are interwoven and dynamic, able to stretch, shrink and jiggle.

  • It is a ringing confirmation of the nature of black holes, the bottomless gravitational pits from which not even light can escape, which were the most foreboding part of his theory.

  • Conveyed by these gravitational waves, power 50 times greater than the output of all the stars in the universe combined vibrated a pair of L-shaped antennas in Washington State and Louisiana known as LIGO.

  • More generally, it means that a century of innovation, testing, questioning and plain hard work after Einstein imagined it on paper, scientists have finally tapped into the deepest register of physical reality, where the weirdest and wildest implications of Einstein’s universe become manifest.

  • Members of the LIGO group, a worldwide team of scientists, along with scientists from a European team known as the Virgo Collaboration.

  • When Einstein announced his theory in 1915, he rewrote the rules for space and time that had prevailed for more than 200 years, since the time of Newton, stipulating a static and fixed framework for the universe. Instead, Einstein said, matter and energy distort the geometry of the universe in the way a heavy sleeper causes a mattress to sag, producing the effect we call gravity.

  • Scientists have announced the discovery of gravitational waves, ripples in the fabric of space time that were first anticipated by Albert Einstein a century ago.

  • The announcement is the climax of a century of speculation, 50 years of trial and error, and 25 years perfecting a set of instruments so sensitive they could identify a distortion in space time a thousandth the diameter of one atomic nucleus across a 4 km strip of laser beam and mirror.

  • The phenomenon detected was the collision of two black holes. Using the world’s most sophisticated detector, the scientists listened for 20 thousandths of a second as the two giant black holes, one 35 times the mass of the sun, the other slightly smaller, circled around each other.

  • At the beginning of the signal, their calculations told them how stars perish: the two objects had begun by circling each other 30 times a second. By the end of the 20 millisecond snatch of data, the two had accelerated to 250 times a second before the final collision and a dark, violent merger.

  • This observation is truly incredible science and marks three milestones for physics—the direct detection of gravitational waves, the first detection of a binary black hole, and the most convincing evidence to date that nature’s black holes are the objects predicted by Einstein’s theory.

  • The scientists detected their cataclysmic event using an instrument so sensitive it could detect a change in the distance between the solar system and the nearest star four light years away to the thickness of a human hair. 


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