Posted tagged ‘science’

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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Brave New Worlds

May 2, 2016

You may have caught this news, but today Nature published a report on the discovery of three earth-scale planets in orbit around just about the least impressive star it’s possible to be.

Edvard_Munch_-_Starry_Night_(1922–24)

What’s most intriguing is that the dimness of that parent star — now known as TRAPPIST-1, after the instrument at the heart of this discovery — makes it just possible (if you squint just right) to glimpse a possible opening for life on its planets.

It’s tricky, because the two better-characterized planets are terribly close to their sun, with orbits of 1.5 and 2.4 days.  But TRAPPIST-1 is what’s called an “ultracool dwarf” — and even at that distances, the two planets would have equilibrium temperatures that are pretty damn hot.  But — if everything broke just right, there would be some locations that could be cool enough to support liquid water on the surface.

That’s one of the big pre-conditions exobiology researchers/dreamers imagine would be valuable/necessary for the emergence of life beyond earth.  Given how many ways we can imagine (and all the ways we can’t) that those circumstances might not pan out, I wouldn’t hold my breath waiting for a signal from our new friends on a distant world.

But the real juice behind this finding comes from the fact that these planets are decent candidates for transmission spectroscopic analysis of their atmospheres (if they have them) during their transits across the face of their star.  All it will take is the next generation of large, infrared-capable telescopes:  the James Webb Space Telescope, scheduled to launch in 2018, and instruments like the Giant Magellan Telescope, the European Extremely Large Telescope, both now starting construction in Chile, and the Thirty-Meter-Telescope, now stalled in Hawaii.

I write more about this over at The Atlantic. It’s a fun tale — a small team pursuing a hunch that has led to a significant (or at least enticing and delicious) advance in our grasp of the possible out there.

So — if you’re tired of terrestrial politics, have some fun contemplating possible home worlds for the Lectroid going by the name of Cruz.

Image:  Edvard Munch, Starry Night, 1922-24

A Big Effing Einstein Deal

February 11, 2016

Just a quick note here as I’m on deadline for a piece on this stuff, but today we got the official announcement of the worst kept recent secret in physics.  Here, via the Guardian, is the TL:DR version of what was said:

On 14 September 2015 at 9:50 GMT, the two detectors of the newly upgraded Laser Interferometer Gravitational Wave Observatory (LIGO) detected a signal.

It was unambiguously a gravitational wave signal because it matched the predictions from Einstein’s general theory of relativity almost precisely.

J.M.W._Turner,_R.A._(1775-1851),_Storm_at_Sea.Christie's

This is huge news, as it is, among other things, the latest and most elusive (so far) direct confirmation of Einstein’s General Theory of Relativity, a theory of gravity that describes what we feel as a force holding our feet to the floor is in fact the local warping of spacetime by matterenergy. (In the case of our feet and our floor — that warping is the dent in spacetime created by the mass of the earth.)

It is as well a triumph of virtuosity in observation and measurement.  The detection of a gravity wave is a simply wondrous an act of human hands and mind.  It is a joy to witness, at least for me.

More after I get the paying work done….

Image:  J. W. M. Turner Storm at Sea 1851 or before.

A 21st Century Mother-and-Child

December 24, 2015

Thought I’d try one post this year without politics or snark, and this is it.

A couple of weeks ago I put this up at The Boston Globe‘s site — and it is, I believe, behind a pay wall.  The Globe is kind enough to release the material back to me to post after a bit, as long as I credit and link back to the original posting (see what I did there) — so here it is.  If the image has any resonance this time of year for you….good.  And if what its maker has to say about the multiplication of possibilities it embodies adds a little joy to the picture?  So much the better.

_________________________

A mother cradling her infant child.

If the better angels of human nature were to prevail, this picture could become one of those pictures — a single frame that captures an essential piece of the 21st century.

Two human beings, stripped way past bare: two brains, connected in a universal human pose, a mother cradling her infant child.

SaxeTakahashi_MRI_April2015

Rebecca Saxe, a neuroscientist (and my colleague) at MIT, is a maestro of the camera that can make such images, the functional magnetic resonance imaging machine, or fMRI. To create an fMRI portrait, a subject must lie still inside a narrow cylinder, the inside of a giant electromagnet. The artful manipulation of electromagnetic fields catches the brain in the act — not quite the act of thinking, but of working, nerve cells grabbing oxygen to power the action that ultimately adds up to an idea, a gesture, a feeling.

Making a functional magnetic resonance image demands a lot of its subjects. In a return to the earliest days of photography, you have to lie still for minutes to allow the fMRI machine to complete its tour of your skull. “Moving just a millimeter leaves a blur on the screen,” as Saxe writes at Smithsonian.com. “The mother and baby must hold their pose, as if for a daguerreotype.”

Saxe’s work centers on a fundamental question: How people grapple with the realization that other people have thoughts inside their heads — an area of research called “theory of mind.”

Becoming aware of the fact that people around you are thinking and learning to analyze what those thoughts might be, is a capacity that human beings develop over time — which has led Saxe to attempt to make fMRI images of ever younger children. That allows her to track how growing brains, growing people, form the ability to imagine the reality of other’s minds.

There’s no science in Saxe’s picture of herself with her son — or rather, there’s no data to be used in any formal extension of her theory of mind research. Instead, one reading of the image is simply as a marker, a measure of the current state of a scientific project. Saxe writes that the juxtaposition of her mature brain with the just-getting-started one of her son is the “depiction of one of the hardest problems in neuroscience: How will changes in that specific little organ accomplish the unfolding of a whole human mind?”

That is: This picture captures a key step in the process of discovery — the moment when a human invention extends the reach of human senses into realms that were until then not just unexplored but unreachable. New instruments don’t just reveal more of something, more detail, better precision, or what have you. Often, as here, they open windows onto whole new vistas. We’re a very long way yet from answering Saxe’s question, but in the sight of her and her son’s brains we can recognize that an answer is possible.

That’s reason enough to borrow an afternoon of scanner time — but that’s not the whole story behind this picture. Saxe says she and her colleagues made this particular fMRI image “because we wanted to see it.” She reads in it a specific story, an argument. Mother and Child is an old, old trope, in art and in human experience, and as Saxe writes, there is a reflex to elevate “the maternal values, and the women who embody them” to the exclusion of the possibility (or propriety) of those same women exercising their smarts in any out-of-the-home role.

Mary_Cassat_-_Mothers_Kiss_-_NGC_29879

Saxe with her son, depicted and depicting — as she writes, neuroscientist and mother — collude in the same single frame. That was the goal, to create “an old image made new.” And there it is, in the traditional gesture of a mother kissing her child, and the utterly new view of that caress from the inside out.

To me, for all that Saxe’s gloss is so clearly readable in her picture, there’s a yet broader idea expressed. There’s a lot of loose talk around the so-called two cultures of the humanities and sciences, often presented as two sharply distinct ways of making sense of the world. Saxe’s picture gives the lie to that simplistic framing. Art does many things, but certainly one of them is to give us images that confront us with shards of the strange experience of being human. Science, an artful craft, can do the same — as it does here.

_______________________

Back to regularly scheduled rage, weariness, snark, schadenfreude, celebrations of the discomfiture of our adversaries and random brain bubbles after this.  Happy Saturnalia, all.

Image:  Mary Cassatt, Mother’s Kissbetween 1890 and 1891.

Mountains, Stars, Conflict

May 31, 2015

You’ll forgive, I hope, the self promotion here, but I want to draw attention to an essay I have in The Boston Globe today.

It’s about the controversy over the Thirty Meter Telescope (TMT) that is beginning to be constructed at the summit of Mauna Kea on the Big Island of Hawaii.  Mauna Kea is one of the world’s most significant sites for optical and near infrared astronomy — it’s already home to thirteen telescopes, including the two largest now in operation in the twin Keck instruments.

Jan_Vermeer_-_The_Astronomer

The TMT is designed to have a primary mirror three times the diameter of the Keck ten meter light buckets, with nine times the light gathering area.  Over the last century — which covers the era of large, mountaintop optical observatorys, each similar leap in telescope size has produced startling, powerful discoveries, and there’s every reason to expect the same of the TMT and its planned southern hemisphere counterparts.

But there’s a catch — or something more fundamental than a mere glitch.  Mauna Kea is a sacred site within the Hawaiian tradition, and an environmentally sensitive one, and opposition to TMT has grown from a point of tension to one of direct confrontation.  Construction of the TMT has been suspended, and the governor of Hawaii has called for the removal of a quarter of the existing observatories before the TMT itself begins operating.

In the midst of this confrontation, plenty of people have framed the two sides as another battle in the old war between science and religious belief.  I say in the Globe today that’s a mistake.  A taste:

….the TMT dispute shows where the science versus religion trope goes wrong. The Hawaiian protesters haven’t said that Mauna Kea’s telescopes are inherently impious, or that the data they collect is somehow wrong, or that Hawaiian mythology is a better account of the cosmos. Rather, the value, the joy, the need the observatories satisfy may indeed satisfy many, but not those continuing a Hawaiian tradition that allows its heirs to find connection with memory, with history, with nature — to achieve the same transcendence sought by those who find beauty in the measure of the universe.

That is: The TMT defenders and their opponents seek analogous rewards from their presence on Mauna Kea. Their conflict isn’t between the competing worldviews of science and religion, but between desires that are kin to each other — and that require the same physical space.

Check it out, if your Sunday afternoon tends that way.  Let me know what you think.

Image:  Johannes Vermeer,  The Astronomerc. 1668.

 

So You Want To Win A Nobel Prize…

April 7, 2015

Excellent advice from one who has.

Rule number two in this list of ten commandments goes beyond the needed snark (and the first principle, which might be called the Tao of science: the only way to achieve Nobelity is not to strive for it).

Los_borrachos_o_el_triunfo_de_Baco_1629_Velázquez

This second principle actually says something dead on point on where discovery happens, in an argument that I think bears on much beyond science itself.  It requires that the prize-aspirant should “hope that your experiments fail occasionally.”  Why?

Because:

There are usually two main reasons why experiments fail. Very often, it is because you screwed up in the design by not thinking hard enough about it ahead of time. Perhaps more often, it is because you were not careful enough in mixing the reagents (I always ask students if they spat in the tube or, more recently, were texting when they were labeling their tubes). Sometimes, you are not careful enough in performing the analytics (did you put the thermometer in upside down, as I once witnessed from a medical student whose name now appears on my list of doctors who I won’t allow to teat me even if I’m dying?). These problems are the easiest to deal with by always taking great care in designing and executing experiments. If they still fail, then do them over again! But the more interesting reason that experiments fail is because nature is trying to tell you that the axioms on which you based the experiment are wrong. This means the dogma in the field is wrong (often the case with dogma). If you are lucky, as I was, then the dogma will be seriously wrong, and you can design more experiments to find out why. If you are really lucky, then you will stumble onto something big enough to be prizeworthy.

And with that, a chance to think about non-stupid things for a while.  Open thread, y’all

Image:  Diego Velasquez, The Drunkards, or the Triumph of Bacchus1629.

What Not To Wear To A Comet Landing

November 12, 2014

Amidst all the (justified) celebration of Rosetta and Phylae today — it really is a big deal when a ten year mission ends with the first landing on a comet evah!) — there  was one truly sour note.  This:

Screen Shot 2014-11-12 at 4.59.54 PM

That’s Matt Taylor, Rosetta project scientist.  If you read the profile at (where else) The Daily Mail, you’ll get two impressions. One, that Dr. Taylor really loves his job, his science and this mission — all of which is great.  But two:  he and his interviewer are oblivious about what it might mean to stand in front of millions of science fans, wearing that schmatte.

Nah, this is just dudebro fun, no worries, no-harm-no-foul, why don’t you have a sense of humor stuff.

But it’s not.  There’s not a lot to say that isn’t f**king obvious.  This was and is a truly special occasion.  Lots of people thrilled to watch human reason and ingenuity reach towards the stars have been playing really close attention. Many of them are women.  Some, lots, are girls who might be thinking science could be a really fine life’s work.  That shirt tells them, pretty explicitly:  science ain’t no crap-free zone.

We’ve ample evidence that’s true, sadly.  But damn, way to drive the message home, Matt!

I’ve had friends, women in science, contact me today, asking when this shit will ever stop.  I don’t know.  Not soon enough.

My son is taking his first high school physics class this year.  Last night I was helping him with his homework on momentum, impulse and collisions — kind of relevant to today’s events.  I don’t know if his teachers broke with the curriculum today to watch the Rosetta live feed — but now I’m almost hoping they didn’t.  The girls — and the boys too, dammit — in that class deserve better.

I’ve never met Taylor.  I wouldn’t be surprised if he’s against discrimination in science (or anywhere else),  one who would defend any woman on his team.  I don’t know.

Maybe he’s just clueless stem to stern, with no idea how what he might say or do affects anyone around him.  Or, in fact, he could be a sexist asshole.  Still don’t know.  I generally, perhaps naively, default to that “clueless” rather than “f*cked-up” explanation, until I have affirmative evidence to the contrary.

But as we’ve learned over and over again in issues of race, of gender discrimination, of same-sex rights, it’s not what you believe that matters.  It’s what you do — and Taylor chose to wear this shirt in front of the largest audience he’s ever likely confront.  He may or many not be a sexist guy; he did a sexist thing, one with real world implications.

Repair work is needed.  The ESA/Rosetta folks should to do some, and so should Matt Taylor, however much of a goof he thought he was having.

Oh, and just in case he might accept some fashion advice, here’s Skepchik’s Dr. Rubidium with some very good natured suggestions.  A possible path to repair lies there, Dr. Taylor.