More than a billion light years ago, two massive black holes were engaged in a cosmic tussle of magnanimous proportions. When the black holes finally collided it jostled the fabric of spacetime so hard that it sent ripples across the universe. These ripples — gravitational waves — weakened as they travelled through the cosmos, and by the time they reached the Earth they were so weak that it would require sensors to pick up deviations of the order of a tiny fraction of an atom’s nucleus.

Imagine trying to catch such a signal amidst the cacophony that is terrestrial noise — it would require a phenomenal device. Such a device was eventually built and on September 14, 2015, the Laser Interferometer Gravitational Observatory (LIGO) detected gravitational waves coming from the black hole merger described above. When the team made the official announcement in February 2016, Kip Thorne and Rainer Weiss, two of the original troika were present. The third, Scottish physicist Ronald Drever had been suffering from dementia and couldn’t attend. On March 7, 2017, news broke out that Drever had passed away, leaving behind a legacy few can emulate.

Before Drever started work at LIGO, he worked on some ingenious and comparatively cheap experiments that are now recognized as a strong test for Lorenz invariance — that the laws of physics remain the same in any frame moving with a zero or uniform speed. Drever’s work proved to be a strong test of Einstein’s theory of special relativity. After a stint at Harvard, he set up base at Glasgow, close to Cambridge, home to many world renowned cosmologists who were at that time were very interested in Einstein’s theory of gravitation. Drever set up his own group to build detectors capable of capturing gravitational waves and was soon recruited to Caltech — one of the premier research institutions in the world, where he would join hands with Weiss and Thorne to sow the seeds of LIGO.

At the heart of LIGO is an instrument called interferometer, each of the two designed as four kilometer long arms. A laser source sends a unified beam which after passing through a splitter independently races across the arms, reflecting back from the suspended mirrors at each end and finally combining, perfectly in sync. But, when a gravitational waves passes through this housing, it essentially stretches space, causing the effective length of one arm to increase or decrease. The combined light in this scenario is out of phase — this deviation, albeit a minuscule one, can be detected.

Drever was responsible for the genesis of the LIGO project and for sometime responsible for its execution as well. For the first few years, he continued collaborating with his original team at Glasgow, coming up with novel ideas and advancing technology that would eventually be crucial to the detection of gravitational waves. A lot of Drever’s contributions came at the interferometer end – from working on the initial proof of concept prototype just 40 meters long, to adding upgrades to make the interferometer more tunable with better clarity. His recent work focussed on isolation of experimental apparatus to protect the sensors from sources of noise.

Drever was known to have a strong personality and he frequently clashed, first with Weiss and then with the LIGO’s director Rochus Vogt. There is however no denying his role in the inception of LIGO and pioneering the field of gravitational wave astronomy. Kip Thorne heaped praise on Drever in Science magazine’s report, remarking on his contributions, “Without them I don’t think we’d be here today with the discovery of gravitational waves.” Weiss added, “Many of the ideas in LIGO that make it sensitive enough to detect gravitational wave derived from his pictures.”

The success of LIGO has paved the way for a variety of other earth bound detectors with greater sensitivity. The European Space Agency’s LISA project is basically a space bound version of LIGO. It, being in space allows for more sensitive measurements as I wrote about here. In India, we might have our very own LIGO detector. Less than a week after LIGO’s announcement of first detection, Narendra Modi announced that the funding for a LIGO detector in India had gained an “in principle” approval. It was a minor triumph considering our country reputation for stifling science projects amidst bureaucracy and a host of issues (yes, INO, I am talking about you).

Large scale observatories like LIGO and the proposed INO (India-based Neutrino Observatory) can be a shot in the arm for the Indian science community. It can reduce the brain drain of talent, attract foreign minds and certainly do much more for India’s quest for a Noble than the announcement of a hefty cash prize. LIGO in particular comes with many benefits, being a part of an established collaboration. Moreover, gravitational wave astronomy is the new wave.

It is important to fully understand the magnitude of gravitational waves discovery. Sure, it signals another triumph for Einstein (like he need any!), but moreover it opened a window for astronomers to look at the universe in a completely different light (pun intended). Till now our gaze was limited by technology — the realm of optical and radio astronomy. Gravitational Waves give scientists the power to ‘see’ events that test the limits of physics as we know it. A whole plethora of effects, ranging from – relic radiation from Big Bang to detection of supernovae bursts and black hole mergers, come under the theoretical range of LIGO like systems.

Looking at the universe with the gravitational wave filter can potentially give us clues about the early universe, rewinding time to an instant where the concept of time was born, revealing black holes in their true destructive glory and letting us peer at events like the birth of a galaxy and the death of another. As Szabolcs Márka, A LIGO team member told Scientific American at the event of the LIGO announcement in February, 2016, “The skies will never be the same … From today, we can hear the cosmos. We can see the unseen.” And we have Ronald Drever to thank for it.

Janna Levin, a physicist in Columbia University, in her book, Black Hole Blues and other Songs from Outer Space, describes Ronald Drever’s aura as that of a “Scientific Mozart.” She writes about how his brilliant physical intuition lead to him thinking in pictures and not equations, a thought seconded by Kip Thorne himself. There is however a paragraph in her book which I think is worthy of being reproduced here. Levin writes about the time when Ron was still in Glasgow, before he moved to Caltech: “He could construct something precise and powerful from nothing with nothing but his bare hands and glass cutters and windowpane, bits of paper, rubber bands, stray screws… He had nothing and he could make something admirable out of it.”

With this innate brilliance and creativity, Drever embarked on a mission that few thought would succeed. It was a rocky ride, but success was achieved. LIGO has come a long way, even after Drever retired. But, whenever we hear that almost beautiful crisp ‘blurp’ like sound of two black holes colliding somewhere in space, somewhere in time, we will be reminded that Drever was amongst the few who started it all. Thank you for illuminating the universe, Ronald Drever.

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