Archive for the ‘Science’ category

Quick Heads Up For Some Spooky Action At A Distance Talk

July 30, 2014

Late, late, late I am in getting this out to you, but I’m doing another webcast/podcast for Virtually Speaking Science today.

I’ll be talking to my MIT colleague, David Kaiser, who is a physicist and a historian of science in our Science Technology and Society program.  He’s also an excellent popular science writer, and we’ll use the hour today (and whenever you might choose to listen) to talk Higgs, Bicep2 and gravitational waves (did the very early universe inflate? Are there butt-loads of universes?  How freaking hard is it to make cosmological measurements?*).  And we’ll talk about his wonderful book How the  Hippies Saved Physics — about the Fundamental Fysics group at Berkeley and their engagement with quantum entanglement, Bell’s theorem, spooky action at a distance and the discovery that yup, the universe does behave that strangely…which is why we are now, almost 50 years later, thinking seriously about quantum computing, encryption and the like:  actual this-world technologies that exploit properties that Albert Einstein thought no properly behaved universe should exhibit.

An_Experiment_on_a_Bird_in_an_Air_Pump_by_Joseph_Wright_of_Derby,_1768

David’s a great explainer — so the opaque shorthand above will become much clearer very soon.  We go on the air at 6 ET — half an hour from now.  Listen here live or later (also on iTunes — search for Virtually Speaking Science and or Levenson and Kaiser) — or join us as part of the virtual studio audience in Second Life, hosted by my favorite (as in, my childhood) science center, San Franciso’s Exploratorium.

*Spoiler:  Very, very hard.

Image:  Joseph Wright of Derby,  An Experiment on a Bird in an Air Pump1768

For A Good Time On The Intertubes Today (And Forever): Annalee Newitz Takes Survival To Extremes

April 23, 2014

Very short notice this time, folks, but once again, I’m doing the funny intertube-radio thingee.  Today’s broad/podcast brings io9 founding editor Annalee Newitz in to talk about her book Scatter, Adapt, And Remember.*

We’ll be talking at 5ET, 2PT (about an hour and half from now).  Listen live or later on Virtually Speaking Science, or join us in the virtually live studio audience at the Exploratorium’s joint in Second Life, where an implausibly tall and fit Levenson avatar will interrogate Annalee’s robot self.

The focus of our chat — death, destruction, and the possibility of slipping the noose.  Annalee’s book looks at what it will take for the human species to survive another million years — avoiding the threat of mass extinction along the way.  Her book really does two things.  For one, it provides a very good short introduction to the science of mass extinction, what we know and how we’ve figured out about the five times in Earth’s history that ~75% or more of all species on the planet went caput.  Then in the second half, Annalee examines the threats humankind have already confronted, looks at what that history tells us about current dangers, and writes about the ways we can now think about near and long term escapes from the worst outcomes.  It’s a combination (as you’d expect from the mind behind the “We Come From The Future” brigade over at io9) of bravura science writing — imaginative and rigorously grounded accounts of current inquiry — and plausible, exciting speculation.

David_Teniers_(II)_-_Apes_in_the_Kitchen_-_WGA22060

To emphasize:  this isn’t a work of speculative writing, fiction or non-fiction.  It’s an argument that includes speculation, given its weight through the third element of  Annalee’s title:  “Remember.”   There’s a beautiful section in the middle of the book in which Annalee discusses the science fiction of Octavia Butler.  There, she grapples with the nub of the book.  Whatever actual path(s) we take, should descendents of 21st century humans persist for geologically noticeable swathes of time, they will do so as one or many species increasingly divergent from our own.  What will be human about them, Annalee argues, will turn on the power and persistence of memory.  That sounds exactly right to me.

Come join us for the chat.  Should be fun…and more than that too, I hope.

*You can take up that title’s Oxford comma-hood in the comments, if you’re that kind of person.  Me, I’m an agnostic.

Image:  David Teniers the Younger, Apes in the Kitchen, c. 1645.

The Most Exciting Sentence I’ve Read This Decade…

March 18, 2014

…Would be this one:

 We find an excess of B -mode power over the base lensed- CDM expectation in the range 30 < ` <  150, inconsistent with the null hypothesis at a significance of >  5 δ.

That’s from the abstract to this paper, released yesterday, in which the team using the BICEP microwave detector at the South Pole reports on their analysis of three years of data taken from 2010-2012.

So what’s that all about?  It’s the best evidence yet that a fundamental pillar of Big Bang cosmology is right, that a concept named inflation does in fact describe what happened within the first instant of the formation of our universe.  Here’s how Alan Guth, the inventor of the idea describes it:

This theory is a new twist on big bang theory, proposing a novel picture of ho the universe behaved for the first minuscule fraction of a second of its existence.

The central feature of the theory is a brief period of extraordinary rapid expansion, of inflation,  which lasted for a time interval perhaps as short as 10^-30 seconds.  During this period the universe expanded by at least a factor of 10^25, and perhaps a great deal more. [Alan Guth, The Inflationary Universe, p. 14.]

Guth’s initial version of inflation theory has been refined significantly since its origins in the late 1970s, and in its modern form inflation has become part of the basic toolkit of cosmological investigation.  The universe we observe doesn’t make sense unless something occurred to explain, for just one example, the way the universe looks basically the same everywhere, when viewed on the largest scale.  Inflation as the idea has evolved has become the best available explanation (though there have been competing models) for this and other observed cosmological properties.  But the challenge has been to find some tell-tale sign that shows* that inflation actually happened.

It’s been clear for a long time where such signs might lie:  in the cosmic microwave background (CMB),  a snapshot of the cosmos taken at a moment called “recombination,” when the universe cooled down enough to permit electrons and protons to come together to form (mostly) neutral hydrogen atoms.  Photons — light — that up till that moment had been embraced in electromagnetic dances with charged particles were then unshackled to fly freely through space, carrying with them the traces of where they’d been just before that liberation — which came just 380,000 years after the big bang.

J.M.W._Turner_-_The_Beacon_Light

Over time (13.8 billionyears), thatextremely hot (energetic) spray of light has cooled to 2.7 Kelvins — 2.7 degrees above absolute zero — and is now detectable as those very long wavelengths of light called microwaves.  This  microwave background was identified in 1965 as a generalized blur covering the entire sky; increasingly sophisticated measurements have revealed more and more detail.  Over the last twenty fiveyears those observations have turned into a probe of what happened between the big bang and the flash of the CMB itself:  each newly precise measurement constrains the possible physics that gave rise to the details thus revealed.  Step by step, each new level of detail narrow the options for what could have occurred during the big bang era — and the chain of events that lead from cosmic origins to us becomes increasingly clear.

In the 1990s,  improving resolution of CMB images revealed spots on the sky where there is slightly more energy in that microwave background — corresponding to regions in the early universe with slightly more matter-energy than surrounding regions.  Such variations account for why there are lots of galaxies full of stars in some places, and vast voids in other:  over millions and billions of years, gravity can work on very slight variations in initial density to sort matter into that kind of pattern.

With the advance of both space and ground based microwave imagers, it’s become possible to sample the CMB in vastly greater detail, and thus uncover much more than the simple (easy for me to say) evolution of structure in the universe.  For example, CMB researchers have identified several acoustic peaks in the background — literally, the ringing of the early universe, pressure waves produced by the interaction of light and matter in the very early universe.  The particular properties of those peaks reveal basic facts about the universe — and help distinguish between different theories about how we get the cosmos we inhabit from the big bang whose traces we see in the CMB.

Before today, the state of play was that CMB results were most consistent with the  predictions of inflation, compared with other candidate ideas.  At the same time though, observations that are consistent-with are not the same as direct observations of the cosmological equivalent of the miscreant’s fingerprints on the knife.  That’s what the BICEP results deliver.

In simplest terms:  modern theories of cosmic inflation say that immediately after some tiny perturbation occurs that marks the birth of a universe, it gets pulled apart by inflation — which you can think of as negative gravity, a gravitational field that stretches space-time.  The inflationary episode is so powerful that it expands the infant universe by orders of magnitude in fractions of a second — as some say, inflation provides the bang in the big bang — and it’s so violent that as space-time undergoes such wild tugs, ripples form.  Those ripples are gravitational waves — predicted by Albert Einstein, inferred from the behavior of pulsars, but never detected directly.  An observation of such primordial fluctuations, variations in the strength of the gravitational field from point to point in the early universe, would offer the first direct glimpse of traces of an inflationary episode marking the birth of our cosmos.

And that’s what BICEPs results contain:  the team led by John Kovac at the Harvard – Smithsonian Center for Astrophysics, Clem Pryke at the University of Minnesota, Jamie Bock at Caltech/JPL, and Chao-Lin Kuo of Stanford and SLAC report the detection of the signature of gravity waves in the CMB with the properties corresponding to those predicted to be produced by inflation.

In slightly more detail, the BICEP experiment observed a particular pattern of polarization in the light (microwaves) of the CMB that inflation would be expected to produce.   (Many more details:   web resources from the BICEP team and partner institutions;  quick semi-technical gloss on the results from Sean B. Carroll;  Matt Strassler’s take; Dennis Overbye’s account in the NYT.)

One key caveat before the wind up:  this is one result from one group.  It is reported with great confidence (that five sigma claim).  But something this big needs independent confirmation — data from the Planck satellite for example, or more ground based observations from other microwave detectors.  This isn’t yet a done deal.

Such confirmation (or disproof) will come fairly quickly — a few years at most.

In the meantime, assuming the data do hold up, what would that mean (forgive me) more cosmically?

At the very least:  that we now understand in previously unattainable detail how our current habitat emerged from nothing (or better, “nothing”).  That the idea of a multiverse — other patches of space time that underwent an inflationary episode to form island universes of their own — has now gained a boost (if one patch of space-time can inflate, so could others)….

…or to put in mythic terms:  there is grandeur in this view of life (the cosmos).  Paraphrasing an old friend, astronomer Sandra Faber, with this new, richer, more fully realized picture of the birth of the universe we have once again enriched that creation story that only science tells, the one that connects the earth we inhabit today with a process of cosmic evolution that we now can trace back all the way to just the barest instant this side of the point of origin.

A good day.

*To a close approximation — this is physics.  You want certainty, become a mathematician.

[Thanks to Dr Katherine J. Mack of the University of Melbourne, aka @AstroKatie, who helped make sure no egregious errors slipped through.  Any mistakes, major or minor, that remain are mine, all mine.]

Image:  J. W. M. Turner, The Beacon Lightc. 1840

PS:  Bonus video showing one of the founding architects of inflation theory receiving news of the result:

Tonight! ‘Net Radio: Me and Eileen Pollack on “Why Are There Still So Few Women In Science”

March 12, 2014

That’d be my regular monthly gig co-hosting Virtually Speaking Science, tonight, Wednesday March 12, 6 p.m. ET/3 p.m. PT.

Eileen Pollack is now a professor at the University of Michigan, teaching in the creative writing M.F.A. program there.  She’s a celebrated novelist and writer of short fiction, essays, and what is called (alas, in my view — and not her fault) “creative” nonfiction.  You can get hold of her works here.  All in all, hers is an enormously impressive record of a life in letters, of worlds made in words.

Eileen Pollack in 1978 was someone quite different (weren’t we all…) That spring, she graduated from Yale with highest honors in physics — only the second woman in the history of the university to complete that major.  What happened to take someone who was, on the accolades, one of Yale’s most accomplished undergraduate physicists, and turn her to a radically different path?

Pollack answered that question and raised another one in her New York Times Magazine article “Why Are There Still So Few Women In Science?” published last October.  In her case, no one told her she might have a shot at a career in math or physics.  So, as conditioned by her context’s views on female capacity and the maleness of science as any of the male professors who never thought to encourage her, she gave up the joy she found in equations and the ideas they expressed, and moved on.

So far hers is a sorrowful but not unfamiliar story.  The history of barriers to entry in science is a miserable one, but not unknown.  But Pollack’s curiosity — and more — flared in 2005, when then Harvard president Larry Summers mused about a possible biological deficit — at least when it comes to the extremes of mathematical capacity — might explain why men so outnumber women in the physical sciences.  Pollack is gentle with Summers himself, whom she’s known for decades , but the controversy created a need to know the answer to the underlying issue.  It’s a fact that there are many more men than women hold positions in the upper echelons of scientific research.  But why?

Joseph_Wright_of_Derby_-_Experiment_with_the_Air_Pump_-_WGA25892

Pollack’s article, and the book that will emerge from her enquiry, engage that question, and the explanations she’s coming to are at once depressingly reminiscent of her own story, and extend them, to account for the persistence of cultural and social bias even when (a) formal discrimination is prohibited by law and (b) members of a community — like physics departments — pride themselves on their ability to separate emotion and unconscious impulses from the exercise of reason.

In other words:  being smart is no protection against hidden biases, or even against accepting the evidence of bias when rigorously documented…and the revolution isn’t won yet, not by a long shot.

Pollack and I will be talking about all that, the whys the wherefores, and some thought as to what it will take to turn formal commitments to gender equity (and by extension, equity for the whole host of relevant modifiers) into actual practice, the simple fabric of society.

Join us!  Live or later here.  Or, if you are virtually real, at the Exploratorium’s Second Life joint – 6 p.m. this evening, March 12, 2014.

Image:  Joseph Wright of Derby, Experiment with the Air Pumpc. 1768

Raindrops Keep Falling…

December 1, 2013

I’ve always loved this passage in the introduction to M.F.K Fisher’s  memoir-cum-essay-collection The Gastronomical Me:

People ask me:  Why do you write about food, and eating and drinking? Why don’t you write about the struggle for power and security, and love, the way others do?

One paragraph later, she replies:

The easiest answer is to say that, like most other humans, I am hungry.  But there is more than that.  I tseems to me that our three basic needs, for food and security and love, are so mixed and mingled and entwined that we cannot straightly think of one without the others.  So it happens that when I write of hunger, I am really writig about love and the hunger for it, and wormth and the love of it and the hunger for it….and then the warmth and ricghess of hunger satisfied….and it is all one. [ellipses n the original]

People don’t often ask me why I write about science, and not politics or economics or culture or war…the way others do.

But I’ve asked it of myself, and I find myself lining up with Fisher.*  Science is so utterly intertwined with how we live that to write about its history, its discoveries, its many discontents,  implications, way of thinking, is to interrogate politics, culture, conflict, philosophy and everything else…food included.

But still, writing about science is not just a sneaky way to comment on Republican anti-rationality or whatever; it’s not just a means to another end.  I’ve written a book about the science of climate change, and though that book is as much about politics — and human nature — as it is about carbon chemistry and Milankovitch cycles, I remember one encounter I had while researching it.

I was in the woods in mid-New Hampshire in October or so, a research forest, walking around with the scientist who’d spent a couple of decades at least measuring everything he could about that ecosystem.  We were talking about acid rain and the changes he’d been able to document, and all that you’d expect in such a conversation, and then he stopped in his tracks at a little jog in the trail.  “That’s an ash tree,” he said, pointing to what was clearly an old friend.  It was desert-highway straight, tall, in fine health.  “These are one of my favorites,” he said.  “They make baseball bats out of these, which is very satisfying to me.”

Which is to say that there is simple pleasure to be had in the scientist’s life, or better, for most of us who aren’t practicing researchers, in a science-infused view of life.  Sometimes, there’s just the fun of the imagination leaping from the forest to the diamond; sometimes it’s the joy of the puzzle;  or the adrenaline rush of the extraordinary (did you know a wolverine can bring down a moose?  I didn’t until I read this);or — and this is what I think first drew me into the story — it’s simply those moments when science offers up a glimpse of pure, disinterested, astonishing beauty.

Like this one:

blue morpho

This image was made with the help of a friend and sometime co-blogger of mine, Dr. James Bales, assistant director of MIT’s Edgerton Center and a master of high speed photography.  It shows a drop of water striking the wing of a a blue morpho butterfly.  It came about in the context of the work of a group of researchers at or recently of MIT who have been studying how to reduce the contact time between water and hydrophobic surfaces.  Cutting the interval during with sprays of water remain on such surfaces matters to applications like preventing icing on aircraft wings.

It turns out that engineering surfaces with tiny ridges does the trick — so far, the team has managed to reduce contact time by 40%, using surface configurations that can be achieved with readily available tools.  More details here.

That’s all well and good — in fact, better than.  As someone who flies pretty regularly out of Logan Airport, I’m all for anything that erodes the threat of icing.

But why the butterfly?

As Jim tells it, the group knew that they had, in essence, reinvented something nature’s been doing for a long time:  what you see happening on the blue morpho’s wing above is exactly what engineered ridges on aluminum can accomplish.  And the researchers wanted to express that realization in a way that acknowledges the elegance thus implied.  Their own images were more useful than grand, and that’s where Jim came in, with the results you see above…**

…which are to me, before anything else, simply beautiful.

From time to time I do ask myself why write about science.  An answer, not the only one, nor the whole of it, can be seen above.***

*People also rarely — never — juxtapose me with Fisher, but that’s another kettle of fish.  I read her; I get to quote her.

**For those of you who like to think about such things, Jim says that “The tricky bit is getting the lighting just right (involved finding the right angles between strobe, wing, and lens, along with a mirror on the far side of the wing from the strobe to get a good fill light) and getting the timing right.”  (That, by the way, is what good photographers say.  The tricky bits are you know, everything.)

For the ubergearheads among us, Jim reports that the image was made with a Nikon D700, mounting a 70-180mm lens (presumably Nikon’s old macro unit), with a 1.4 teleconverter, a StopShot trigger unit (from Cognysis, in the US) and an Ultra Micro Flash from LaserScribe (an outfit in the UK) which has a flash duration of approximately 10 microseconds.

***Two more images for your delectation can be found below.

All images: credit A. T. Paxson, K. Hounsell, J. W. Bales, J. C. Bird & K. Varanas, used by permission.

blue morpho 2

blue morpho 3

For A Good Time On The Intertubes: The Unreasonable Effectiveness of Mathematics*

November 20, 2013

It’s that time of the month again.

This afternoon at 5 ET I’ll be doing my internet science radio gig as one of three hosts on Virtually Speaking Science.  The others, btw, are Alan Boyle and Jennifer Ouellette.

My guest will by my MIT colleague Allan Adams.  Allan is a physicist — a string theorist, AKA someone who works on problems that have been famously twitted as having no rea world test or validation.

Jan_van_Bijlert_-_Musical_Company_-_WGA02182

That’s a misleading claim on a bunch of levels, some of which are implicated in some recent work Allan and several colleagues have done.  The latest, reported in a paper in Science last summer, uses math derived from string theory that’s been applied to the study of black hole dynamics to investigate what happens as a superfluid — a frictionless fluid whose behavior is described by quantum mechanics — displays turbulence.

That’s a mouthful, to be sure.  Here’s the nub:  a mathematical description of one kind of physical system — a black hole — turns out to explicate the behavior of a very different one, that, as it happens, can be produced, observed and analyzed right here at home.

Think on that for a second.

This is an instance of the most …

…miraculous is the wrong word for it, so perhaps better, astonishing fact about modern science:  it really, really works, and it does so through a path that mathematics opens up.  We can make sense of our surroundings because of what seems to be an invention of the human mind, a system of logic rigorously expressed that can describe and evolve the relations between ideas, concepts and things in the world.  But here’s the weird bit:   that tool, that invention of thousands of years of human culture, does so across every more disparate, ever more encompassing domains — from the lab bench to a collapsed star, for example.  Mathematics as a creation of fallible humans seems to be in some sense an intrinsic property of the universe, which is a much more banal statement than it appears, in one sense, since what it really says is that  mathematical accounts do what people were trying to do with the stuff:  find ways to construct   arguments in forms that can be checked for accuracy and internal consistency that satisfactorily describe, say, the flight of a cannonball or the path of a planet.

So Allan and I are going to talk about all that:  his recent work as an example of the unreasonable effectiveness of mathematics; about how physicists actually use math — what kind of thinking actually goes into doing this kind of work;  and about why string theory, for any paucity of new prediction or unique evidence in its favor is still such a fertile field of inquiry — and what that fact tells you about how science actually advances.

Heady stuff, I know, but I, with my physics degree from the school of having things fall on my head, will keep the conversation working as a way to see into what (a) physicist does.  Allan, you’ll find, is great value, that most fortunate of human who finds nothing but joy in the work he does. That’ll come through — the great pleasure of my work is to get to spend time with people who know cool stuff, find out more, and can’t stop talking about it. That’s what you’ll get in just a little while.

Tune in if you have a chance, or stop by the Second Life live studio experience, or catch it later as  a podcast.

*The phrase “The unreasonable effectiveness of mathematics” was the title of an essay by Nobel laureate physicist Eugene Wigner.  Highly recommended.  It’s concluding thought:

The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve. We should be grateful for it and hope that it will remain valid in future research and that it will extend, for better or for worse, to our pleasure, even though perhaps also to our bafflement, to wide branches of learning.

Image: Jan van Bijlert, Musical Companybefore 1671.

A Bit of Multi-Spectral Awesomeness For Your Delectation

July 9, 2013

This image has been around for a bit, but I just stumbled on it — so here you go:

719590main_Grid-Sun-orig_full

Per the NASA write up, this is a collage of images from the Solar Dynamics Observatory, mostly showing measurements of light at particular wavelenths, w. a bit of other information as well.

I want my own quilt  made to that design.

As the linked material says, the point isn’t just pretty pictures.  It’s that the characteristics of the light (electromagnetic radiation) detected up and down the spectrum reveal very specific details of the processes the produced each particular emission.  See, e.g., the wonderful story of the element that was, then wasn’t, coronium.

One more thing:  this image, or rather the investment required to make all the images that go into this collage, is an example of the kind of nice thing it will be harder and harder to get the longer our current Republican party remains in existence.  Just sayin…


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