Einstein predicted gravitational waves 100 years ago. Here’s what it took to prove him right.
"The “chirp” is bright and bird-like, its pitch rising at the end as though it’s asking a question. To an untrained ear, it resembles a sound effect from a video game more than the faint, billion-year-old echo of the collision of two black holes.
But to the trained ear of experimental physicist, it is the opening note of a cosmic symphony. On Thursday, for the first time in history, scientists announced that they are able to hear the ripples in the space-time continuum that are produced by cosmic events — called gravitational waves. The discovery opens up a new field of scientific research, one in which physicists listen for the secrets of the universe rather than looking for them.
“Until this moment, we had our eyes on the sky and we couldn’t hear the music,” said Columbia University astrophysicist Szabolcs Márka, a member of the discovery team, according to the Associated Press. “The skies will never be the same.”..."
https://www.washingtonpost.com/news...ook-to-prove-him-right/?tid=pm_national_pop_b
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Finding Beauty in the Darkness
"...One hundred years ago, Albert Einstein used his newly discovered general theory of relativity (which implies that space itself responds to the presence of matter by curving, expanding or contracting) to demonstrate that each time we wave our hands around or move any matter, disturbances in the fabric of space propagate out at the speed of light, as waves travel outward when a rock is thrown into a lake. As these gravitational waves traverse space they will literally cause distances between objects alternately to decrease and increase in an oscillatory manner.
This, of course, is far from the realm of human experience. In the absence of alcohol, your living room doesn’t appear to shrink and grow repeatedly. But, in fact, it does. The oscillations in space caused by gravitational waves are so small that those ripples in length had never been seen. And there was every reason to suspect they would never be seen.
Yet on Thursday, the Laser Interferometer Gravitational-Wave Observatory, or LIGO, announced that a signal from gravitational waves had been discovered emanating from the collision and merger of two massive black holes over a billion light-years away. How far away is that? Well, one light-year is about 5.88 trillion miles..."
http://www.nytimes.com/2016/02/14/o...emc=edit_ty_20160212&nl=opinion&nlid=73927810
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Gravitational Waves: What Their Discovery Means for Science and Humanity
"People around the world cheered yesterday morning (Feb. 11) when scientists announced the first direct detection of gravitational waves — ripples in the fabric of space-time whose existence was first proposed by Albert Einstein, in 1916.
The waves came from two black holes circling each other, closer and closer, until they finally collided. The recently upgraded Large Interferometer Gravitational Wave Observatory (LIGO) captured the signal on Sept. 14, 2015. Not every scientific discovery gets this kind of reception, so what exactly is all the hype about, and what's next for LIGO now that it has spotted these elusive waves?...
http://www.space.com/31922-gravitational-waves-detection-what-it-means.html
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Everything you need to know about gravitational waves (in gifs) (with clip)
"Thursday we were all really, really excited about gravitational waves. But maybe you heard all that and were like:
This second-day gif primer will let you join in on the celebrations....
3. But what is a gravitational wave?
Gravitational waves are the ripples in the pond of spacetime. The gravity of large objects warps space and time, or “spacetime” as physicists call it, the way a bowling ball changes the shape of a trampoline as it rolls around on it. Smaller objects will move differently as a result — like marbles spiraling toward a bowling-ball-sized dent in a trampoline instead of sitting on a flat surface.
Einstein actually proposed the existence of gravitational waves almost exactly 100 years ago when he presented his theory of general relativity..."
https://www.washingtonpost.com/news...-about-gravitational-waves-in-gifs/?tid=a_inl
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Einstein, A Hunch And Decades Of Work: How Scientists Found Gravitational Waves (podcast)
"On Thursday, researchers announced the discovery of gravitational waves —wrinkles in the very fabric of space-time.
But behind the headlines and news conferences were decades of hard work, hundreds of scientists and more than a billion dollars in taxpayer funds.
"It's profoundly satisfying that it came out the way that we intended, we'd hoped, we'd dreamed," says Kip Thorne, a gravitational theorist at Caltech who co-founded the project...
The idea of gravitational waves started 100 years ago, when Albert Einstein revolutionized physics with a theory of gravity called general relativity — which reimagined the force of gravity as a warping of dimensions of space and time. The theory made a lot of startling predictions. One of them was that very heavy objects such as black holes should produce ripples in space-time itself..."
http://www.npr.org/sections/thetwo-...work-how-scientists-found-gravitational-waves
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A Simulation Of Two Black Holes Merging
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