Posted tagged ‘Nobel’

Cosmic Goodness (Immigrant Edition)

October 3, 2017

Here’s a welcome respite from the ongoing hellscape of GOP-dominated America:

Three American physicists have won the Nobel prize in physics for the discovery of gravitational waves, ripples in the fabric of spacetime that were first anticipated by Albert Einstein a century ago.

Rainer Weiss has been awarded one half of the 9m Swedish kronor (£825,000) prize, announced by the Royal Swedish Academy of Sciences in Stockholm today. Kip Thorne and Barry Barish will share the other half of the prize.

If you want to listen to a gravitational wave — the sound of two black holes colliding — here you go:

For more detail on what the prize is for, here’s a lovely, relatively brief lecture — very accessible — on gravitational waves and what it took to detect them, delivered by my MIT colleague Nergis Mavalvala:

And if you want to go a bit deeper, MIT’s Rainer Weiss, one of the three laureates, offers longer, somewhat more technical account:

You can follow this prize — as so many before it — back to Albert Einstein.  As Mavalvala explains, the concept of the gravitational wave emerges directly from Einstein’s theory of gravity, the General Theory of Relativity.

To say “directly” is, as usual, a bit of misrepresentation.

Yes: calculation within Einstein’s 1915 theory does end up at a prediction of gravitational waves, but neither the history of that calculation nor the human story moved down anything like a straight path.  First, in 1905, Henri Poincare suggested that gravity waves might exist.  Then, in 1915, with his new mathematics of gravity, Einstein began to wonder if his theory would yield such waves, soon concluded it would not, then revisited the question, still during WW I, and proposed that three different examples of gravitational oscillations might actually be real.  Then, 1922, Arthur Eddington (who had led the eclipse expeditions that confirmed the underlying general theory three years before) showed that two of the three forms Einstein had proposed were mathematical mistakes, born of the choice of coordinate system Einstein used for his earlier calculation.

Einstein pursued other projects for a while, returning to gravitational waves in the 1930s, after emigrating to the US.  Working with an assistant, Nathan Rosen (of the Einstein-Podolsky-Rosen paradox-that-isn’t), he wrote a paper concluding that gravitational waves do not exist, full stop.  The two men submitted the paper to Physical Review, which then sent it on for review.  The reviewer, Howard Percy Robertson, found a confounding error. On being informed,  Albert Einstein was not amused:

Einstein’s reaction was anger and indignation; he sent the following note to [PR editor John] Tate [10]:

July 27, 1936
Dear Sir.
“We (Mr. Rosen and I) had sent you our manuscript for publication and had not authorized you to show it to specialists before it is printed. I see no reason to address the—in any case erroneous—comments of your anonymous expert. On the basis of this incident I prefer to publish the paper elsewhere.”
Respectfully
Einstein
Still, Robertson was right, as Einstein’s next assistant, Leopold Infeld confirmed.  He told Einstein what he’d learned, and the older scientist listened:
Infeld refers to the day before a scheduled talk that Einstein was to give at Princeton on the “Nonexistence of gravitational waves”. Einstein was already aware of the error in his manuscript, which was previously pointed out by Infeld. There was no time to cancel the talk. The next day Einstein gave his talk and concluded, “If you ask me whether there are gravitational waves or not, I must answer that I don’t know. But it is a highly interesting problem
Einstein had already resubmitted his original paper to another journal, and the work was in proofs, which led to a scramble, and the final outcome:
“…After finding relationships that cast doubt on the existence of gravitational fields rigorous wavelike solutions, we have thoroughly investigated the case of cylindrical gravitational waves. As a result, there are strict solutions and the problem is reduced to conventional cylindrical waves in Euclidean space”.
Einstein was often swift to annoyance. He could, though, on reflection, be corrected — as he was here.
“I want to thank my colleague Professor Robertson for their friendly help in clarifying the original error.”

The issue remained, though, that gravitational waves were complicated to model, and hence even to imagine detecting.  The article linked above and again here is a history of the idea, and it shows how much thinking and doing — for decades — went into the moment of discovery this prize celebrates.

And that just gets us to the gate of the work behind this year’s physics Nobel.  Weiss first came up with the idea for the detector that ultimately heard two black holes colliding almost exactly fifty years ago, after teaching MIT’s introduction to general relativity. The next decade, he began the collaboration with fellow laureate Kip Thorne, the near legendary Caltech general relativist to advance the idea of a large-scale interferometer as a gravity wave observatory.  The next key collaborators, Ronald Drever, who died last year, and the third prize-winner, Barry Barish, credited with the transformation of Weiss’s original notion into a full fledged and ultimately enormous lab, joined soon after.  The actual detection took place a mere four decades on.

And it’s beautiful — as Einstein once said of other work, an example of “the highest form of musicality in the sphere” of scientific endeavor.  The scale, the unholy precision, and the extraordinary extension of human perception into the most forbidding recesses of the universe are simply sublime, glorious and terrifying.  In these wretched political times, the notion that some of our species can create on such an encompassing canvas is…a balm, at least.

And, not to harsh that mellow, but because everything is political to me these days, a final thought.  Einstein, an immigrant, discovered the underlying concept.  Rai Weiss, born in Berlin in 1932, escaped with his family from the Nazis first to Prague and then New York.  Mavalvala, featured above, a key contributor to the ultimate instrument that made the detection, came to the US to pursue knowledge at the highest level from her home in Turkey Pakistan [apologies for the error].  Many, many more people from all over dedicated days and nights and years of their working lives to making this happen.

This is the intellectual and cultural capacity the GOP seeks to erode.  That makes them philistines, and worse: saboteurs of the American capacity to create both basic science and all the expected and unanticipated possibilities for human well being that flow from “musicality in scientific thought.”

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