“We Can Listen to the Universe Now” –LIGO Gravitational Wave Discovery





“We had thought the first signal would be some little small thing poking up out of the noise and we’d have to work really hard to understand what it was,” Nergis Mavalvala – the Curtis and Kathleen Marble Professor of Astrophysics and the Associate Department Head of Physics at the Massachusetts Institute of Technology (MIT), and a member of the MIT Kavli Institute for Astrophysics and Space Research (MKI). “But in fact, the signal we got is a very clean and beautiful event. It tells us that the binary black holes were located about 1.5 billion light years away. They whirled around each other at nearly the speed of light before a collision that was so powerful, it converted approximately three times the mass of the Sun into gravitational wave energy—in just a few tenths of a second!”

“To me, this detection means that the stars are no longer silent,” says Matthew Evans – is an Assistant Professor of Physics at MIT as well as a member of MKI. His work centers on gravitational wave detector science, The frequencies of gravitational waves that LIGO is designed to detect are actually in the human audible range. So when we’re working on LIGO, we often take its output and put it on a speaker and just listen to it. For this binary black hole system, it made a distinctive, rising “whoooop!” sound. It’s not that we just look up and see anymore, like we always have—we actually can listen to the universe now. It’s a whole new sense, and humanity did not have this sense until LIGO was built.”



“We often whistled to demonstrate what we thought these smashing black holes might sound like, and it turns out if you play the piano or a keyboard, you can also make a similar sound,” said Rainer Weiss – is a Professor of Physics, Emeritus at MIT, among the first to explore the kind of instrumentation necessary to detect gravitational waves and proposed the LIGO project with two colleagues in the 1980s. “Do you know what a glissando is? It’s when you run your fingers very quickly across the keys. If you started at the bottom of a keyboard and went all the way to the middle C and then hold that note for a little bit—that’s what this black hole signal happened to be. “I keep telling people I’d love to be able to see Einstein’s face right now.”

The Daily Galaxy via MIT Kavli Institute for Astrophysics and Space Research

Image credit:  LIGO detects gravitational waves from merging black holes, LIGO, NSF, Aurore Simonet



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