The sounds of space:

'Chirp' from gravitational waves sent ripples through science community

Reviewed by Sheilla Jones

Winnipeg Free Press, April 23, 2016

Black Hole Blues and Other Songs from Outer Space

By Janna Levin

Arnold A Knopf, 256 paged, $26.95

If two black holes collide out in space and nobody in the universe hears it, did it really happen?

The difficulty of finding any evidence of such cataclysmic events — and two black holes colliding with the energy of a million-billion suns is indeed cataclysmic — is that black holes swallow up all that energy. No radiation can escape their enormous gravitational pull, and there is no radiation, heat, light or sound for anyone to see. Ever.

Albert Einstein theorized in 1915 that great perturbations of space-time could send out waves that would ripple out through the universe. What if it were possible to capture evidence of those ripples in the form of gravitational waves?

What started as a seemingly impossible dream more than 40 years ago to "listen" for gravitational waves was realized in September 2015 with a "chirp" heard around the world. The Laser Interferometer Gravitational-Wave Observatory (LIGO) recorded a tiny noise, measured using lasers fired down a pair of four-kilometre-long tubes in detectors in both Washington state and Louisiana. The discovery was announced with great fanfare in February 2016, and there’s already talk of a Nobel Prize.

The heroic uphill battle to detect gravitational waves, fuelled by the tenacious hope of a great scientific discovery, drives Black Hole Blues and Other Songs From Outer Space. Unlike most science writers, author Janna Levin personalizes the tale of the search for gravitational waves by making herself part of the story. She spends a lot of time with two members of "The Troika" that originally designed and built LIGO — the straight-talking, practical Rainer Weiss, and mathematical perfectionist and dreamer Kip Thorne. Family and colleagues had to speak for the third member — the creatively brilliant Ron Devers, sidelined by dementia.

The story of the campaign to fund and build LIGO was, from Levin’s perspective, a story of human tragedy and triumph, replete with clashing egos and indifferent bureaucrats. But Levin makes almost no mention of the fierce international competition to be first to get a detector up and running.

In 2001, a British/German consortium was building a much smaller detector with 600-metre tubes near Hannover, Germany — ahead of the Americans. Both teams were struggling with how to suspend mirrors at the end of the tubes and keep them perfectly still to precisely reflect laser beams. The apparatus was so sensitive, the LIGO detectors could be affected by storms off the Labrador coast or earthquakes in China. The Hannover group had advanced to "growing" their own silica wires, using the fine glass threads for suspension. The LIGO group, meanwhile, was still using old-fashioned piano wire.

It was, however, the inability of the founding troika to work together at Caltech — the "blues" referred to in the title — that threatened to derail the most expensive project in the history of the National Science Foundation. This human element is what makes Black Hole Blues such a compelling read.

Still, it was only two pages into the book that something seemed very wrong. Levin, a professor of physics and astronomy at Columbia University, tells the story as if the dream of hearing gravitational waves were still years away. It turns out Levin completed the book manuscript and sent it to Weiss and Thorne to review the very day a wave moved the mirrors and a "chirp" was heard.

A proverbial cone of silence immediately descended over the research team until that chirp could be verified. The discovery came just a few hours after the newly refurbished LIGO detectors in Washington and Louisiana were "locked on" for the first time. It seemed improbable, nearly impossible, that a gravitational wave generated by two black holes colliding 1.3 billion years ago should pass by Earth just after the detector was turned on again — but it was true.

Levin didn’t know until December, when she received a confidential email confirming the discovery from the director of LIGO. It was still a secret, but it gave her just enough time to add an epilogue to the book before it went to the printers. There wasn’t even time to change the book jacket.

It helps to read the book with that last-second publishing scramble in mind.

Sheilla Jones is the author of The Quantum Ten: A story of passion, tragedy, ambition and science. She appreciates the value of human drama in telling a good science story.