New Blog Entries

You'll Read This Post If I Mention Michael Jackson
By WILLIAM OREM • Jun. 28, 2009 @ 14:53 GMT

image: currentnewsstories

See, I knew you would.

The late King of Pop is dominating the blogosphere this week, and probably well into the remaining summer. Radio, television, tweets, he’s all that. The Gloved One rules in death as he did in life.

So why bring him into a science blog? Two reasons.

One is that moments like this provide fascinating anthropological material (stay with me here). As someone who--forgive me--doesn’t care about the Man or His Music, I’m having a disorienting experience watching absolutely enormous sections of my species go into paroxysms over an individual who was, even by visage alone, disturbingly bizarre. Throw in the delusions, disfigurement, various allegations of child abuse, and the question of why so many millions see someone transcendently wonderful in MJ becomes one for the evolutionary biologists.

I’m not kidding on this. A fair assessment of crowd behavior would conclude this is not an entertainer much of the world is mourning, but a kind of lesser deity. Like Elvis, MJ will no doubt begin making resurrection appearances soon (Princess Di was seen by mourners before Buckingham Palace had even concluded the official ceremony surrounding her death).

My guess is what lies behind my alienating experience this week is that my brain hasn’t popped the King of Pop into the slot that almost certainly exists in all primate brains for “group leader.” Once someone occupies that cognitive niche--and fame would certainly do it, though I suspect being associated with rhythmic music triggers some very old cortical sub-routines as well--it becomes hard to see the person rather than the internal representation of the person. There are sound evolutionary reasons why we should expect to find ourselves falling in behind a King, as well as why we should *not* to be able to perceive said King objectively once we have identified him.

But my interest is drawn more this month to a different set of ancient and ubiquitous symbols. As a space enthusiast, I find it fascinating how frequently, in describing the Morte d’Michel, we invoke cosmic imagery.

After all, MJ wasn’t just the King, he was a star. Indeed, he was a superstar, presumably a more massive stellar object than others in the local heaven. His rise was meteoric; he shone more brightly than others in his orbit; perhaps it was inevitable he would crash and burn.

This seems to be a cultural universal: as far back as ancient Greece the heroes of the day—say Herakles—were, upon their death, promoted into constellations. Now we talk in commonplace tones about Brad Pitt’s star power, or Miley Cyrus’ rising star, or Britney Spears’ shooting star. Do we love the man who brought us the Moonwalk, temporarily freeing us from gravity’s chain? Adorn him with extraterrestrial metaphors.

A non-human anthropologist might see in these ubiquitous gestures an impulse, deep in the human psyche, to leap free of the planet’s surface. Even before we knew what was out there, we expressed a profound desire to travel among the greater galaxy. It’s as if concomitant with the emergence of human consciousness is a teleological drive eventually to become space-farers.

To be sure, the critical phrase there is “as if.” Evolution has no teleology. The mistaken belief that it’s trying to get somewhere led us into the various ideological disasters of the last century.

But there may still be room, in a full description of humanity, for a quality we once called fate. We are the species that looks up. And with our song and dance, our ancient social patterning, our joy and our audacity, we’re the only one that stands a chance of making a new home there. I think our fate is to become sky-travelers, and more--one day, to sing among the stars.

image: D Sharon Pruitt

Entanglement with Irony: Spooks cut funding for spooky physics
By VLATKO VEDRAL • Jun. 10, 2009 @ 12:08 GMT

Every human endeavor has a bittersweet taste. “A cup of honey no one has yet drunk, without mixing it with a cup of gall”, said a Montenegrin nineteenth century bishop, warrior and poet in one of his epics on the struggle of his people against the mighty Ottoman Empire (admittedly, the original reads much better, but then I am a physicist, not a linguist). So it is with science. Last week’s issue of Nature contains a beautiful paper by David Wineland’s group at NIST in Boulder Colorado, who managed to create the first form of a mechanical entanglement between vibrating pairs of ions. But the same issue of Nature, in another article, reports on the announcement of IARPA (Intelligence Advanced Research Projects Agency, according to Wired “It’s like DARPA for Spies”) to cut funding for Wineland’s experiments. Wineland is among a number of other illustrious US scientists, such as William Phillips, the Nobel Prize Winner for laser cooling, who suffered the same fate.

The said paper by Wineland’s group is significant in that it shows entanglement between mechanical vibrational degrees of freedom of two ion pairs. Vibrational entanglement has, of course, been analyzed theoretically many times, but it has never been achieved experimentally before in such a clear and conclusive manner. Wineland’s is a very involved and sophisticated experiment, where entanglement is first created between energies of two pairs of ions (which itself is an achievement, though done a number of times before). This is then transferred onto the vibrations, so that ion pairs oscillate in unison, but their degree of correlated motion is higher than anything that can be done by classical oscillators (such as two pendulums). All manipulations are achieved by shining laser pulses of appropriate frequency. Once vibrational entanglement is achieved, its presence is confirmed by the reverse actions. Suitable laser pulses transfer entanglement to the energy degrees of freedom and this is then measured.

Experiments of this type and level of sophistication take decades to achieve. During this time, it is very important to have a sustained level of funding not only for equipment, but also for staff (typically between 5 and 10 physicists are continuously needed to realize something like this). A typical grant lasts for 3 to 5 years and this means constantly fighting for renewals and extensions in order to achieve a goal that might take 20 years or so (like ion-trapping, laser cooling, Bose condensation etc).

The decision of US government to cut funding for Wineland is doubly ironic. Firstly because of its bad timing: the cut is announced in the same week as his latest groundbreaking experiment is published in Nature. Secondly –and this is the irony—that very experiment might provide a way of doing something that is crucial to military intelligence. Military activity is all about tracking the movement of the enemy. This can be accomplished in many different ways, but one of them is detecting a very low vibrational level of noise caused by the movement of nearby objects. Vibrations are, of course, all around us, but the trick is to detect the meaningful ones (the so called “signal”) from the background ones (known as the “noise”). Classical physics has a limit, called the shot-noise limit, but this limit can be overcome and much improved by quantum mechanics. Such techniques form a basis of the subject called quantum metrology; Wineland is one of the world’s leaders in this particular activity. Therefore, Wineland’s experiments may pave a way to efficient detection of very weak vibrations using quantum entanglement.

Regarding the funding cuts, the point is that academics these days (in the US possibly more than anywhere else) have to live in the real world and compete for its limited resources. Grant application writing forms a significant part of a (senior) scientist’s time. Here in UK, for instance, the success rate for governmental funding is almost as small as 10 percent. This means having to write on average 10 proposals (each requiring a substantial investment of time and effort) in order to be granted funding for just one of them. The US conforms to similar statistics.

Having a year or two of a gap in one’s grant income could be enough to terminate experimental activity for good (and I definitely know of cases where this has happened). Academics are therefore continuously faced with very uncertain futures that are more typical for business and industry. The decision of US military to cut funding is probably not a big surprise for my colleagues in America—they are used to it (by now, so are we in UK). However, it is always a big question if the short term thinking that pervades business and industry (for a good reason) is really appropriate when it comes to achieving academic excellence (which is almost always based on long term projects and far reaching ideas that take decades to mature and painstaking research to realize).

But enough of the politics behind science. Let’s be forward-looking and finish on a positive note. An important future experiment would be to increase the mass of the entangled oscillators (as entanglement is meant to decrease with mass and there could indeed be some critical size of the system beyond which entanglement is impossible). This I think can be achieved fairly straightforwardly by Wineland’s group. The other is to have more than two entangled oscillators. This could be a much harder experiment to execute (as decoherence could prevent the creation of entanglement), but it’s very important since it is ultimately linked with two very fundamental and related issues: the universality of quantum physics and the possibility of large scale quantum computation. I believe that the confirmation of the second type of entanglement is also just a matter of time, especially given the rate of progress of groups such as Wineland’s.

The exciting thing, of course, is that (despite my optimism) there is always a chance of failure, which is then usually followed by a discovery of another important physical principle hitherto unknown to us. Either way, it is crucial to push the limits of science forward. My firm belief is that Wineland will overcome the setbacks caused by the recent funding cuts and get there in the end. And who knows, maybe the military will realize the error of their ways and reverse the decision to cut.


Angels and Demons...
By KEVIN BLACK • May. 25, 2009 @ 11:42 GMT

...or How I Learned to Stop Worrying and Love Pseudo-Science.

Spaceships inexplicably whizzing by in space with mysterious 'anti-gravity' forces keeping everything nicely in place. Ordinary people transformed to superheros by ridiculously high exposure to radioactivity. Alien creatures that look mysteriously human (except for the green skin and claws) speaking impeccable English.

The typical scientific blunders that form the usual fodder of low (and high!) budget Hollywood productions have always left me suppressing a cringe as I try to get lost in cinema magic. However, none of this can hold a candle to the opening scene of 'Angels and Demons' released last weekend. As the crane shot zoomed down the 100 meter shaft down into the cavern where the ATLAS experiment at CERN is located, a small sideways smile formed on my face as they showed one of the wheels of the muon spectrometer that I have been working on for the last 4 years.

As surprising as it was to see that the Hollywood version of my experiment had a control room built into the wall of the cavern only protected from the intense radioactivity by a slim piece of glass, there was a bigger shock to come. As I scanned the imaginary control room for the next Bruce Banner candidate (of incredible Hulk fame), I discovered that the experiment (that a few thousand of my fellow physicists have spent decades designing, building, and now operating) had a secret. The secret dual purpose of the LHC is apparently to siphon off enough anti-matter and destroy the pope and Vatican City along with it!

Ok, to be fair that isn't quite the plot of the movie. Nonetheless, the basic premise of the movie is centered on the idea that a large amount of anti-matter is produced and stored by CERN scientists. Everything seems to be going well until one of the scientists is brutally murdered and his eye removed to pass through the retina scanners within the LHC tunnels (an aspect of CERN security which IS actually used).

Enter Robert Langdon. Although still peeved from their previous encounter as transcribed by Dan Brown's previous novel where he helps reveal the apparent truth of the Gospel of Mary, the Vatican is in a bind. After all, when searching for an antimatter bomb hidden in Vatican City who better to call than a bookish symbologist from just north of Boston (I guess the Ghostbusters were on vacation). However, it is soon revealed that the Vatican comes calling on him because it is suspected that an ancient scientific sect may be responsible and seeking retribution for the treatment the Vatican gave Galileo all those years ago.

Talk about holding a grudge.

Fortunately, I didn't have to cringe in horror of the scientific inaccuracies too many times during the film. The rest of the movie was filled with the typical Hollywood plot twists—trying to subtly manipulate the audience into thinking they had solved the puzzle when in fact there was yet another twist around the corner.

In fact, CERN does produce a fair amount of antimatter colliding high energy particles together. As far as I can surmise there are a few major scientific inaccuracies with the antimatter bomb premise: (1) in order to produce enough antimatter for the explosion that the (curiously model-like) female scientist describes, it would, in fact, take roughly 100 million years of LHC running; and (2) storing anti-mater is a bit more complicated than going to Radio Shack and getting one of those fancy glass containers with the flashing LEDs. Actually, the ATRAP experiment at CERN has produced and confined very small amounts of antihydrogen. However, storing it requires a complicated configuration of magnetic fields known as a Penning-Ioffe trap (see image, right). Unfortunately, it's not something you can power with a pair of AA batteries and slip into your pocket.

If you think that propagating false scientific information is harmless think of the recent proclamation of the pope that contraceptives actually cause AIDS. At least no one is likely to die because of the intricacies of a Penning-Ioffe trap being misrepresented. Not wanting to ruin the movie for those who haven't seen it, I won't rant about how the movie ends but only comment that Obi Won Konobi's successful skydive is, to say the least, highly improbable.

The book, which I didn't read, apparently includes Robert Langdon flying across the Atlantic in CERN's space plane which can travel "at themind-numbing speed of 11,000 mph." The effect was that the public CERN webpage included a long FAQ indicating that in fact the space plane was only Brown's ambitious dream.

There was also the character of the CERN director general (a suspected villain who was only posthumously redeemed) that got written out of the movie. Curiously, Tom Hanks has recently been asked to return to CERN and press the ceremonial start up button later this year. I thought about calling up the Symbology department at Harvard but somehow this mystery doesn't seem to require it.


Does God Know He Is God?
By WILLIAM OREM • May. 22, 2009 @ 18:44 GMT

A philosophical diversion (that connects to T.O.E.):

Let’s assume, for the purposes of argument, that there are such things as gods. In fact, let’s assume there is only one God, and that He has the traditionally ascribed attribute of having an infinite mind.

That mind has, within its magical neural architecture, complete knowledge, which we can short-hand for the moment as: “contains all possible true statements in propositional form.” One such statement might be, for example, “On June 17th at 11:59 the sky over Altoona was robin’s egg blue.” Yes, an infinite regress pops up here, as there are also true statements asserting the truth-value of previous statements—“It is true that on June 17th at 11:59 . . .”--and so on. No matter—you can’t crowd infinity.

Now, dismiss the rest of God’s purported attributes; all we’re after is a mind that knows all things. Does such an Infinite Mind—call it the I.M.—know itself to be the Infinite Mind? Does God know He is God?

At first blush, the answer would seem to be yes. There are a few ways to get there. The simplest is that the I.M.’s being infinite is, indeed, a fact (though not a fact of nature, exactly, unless you are Spinoza). As a fact, it is contained, propositionally, in the Infinite Mind. Thus the I.M. knows that it is the I.M., in the same way it knows the shade of blue above Altoona.

There are other ways in. It’s possible that I myself might know the I.M. to be infinite (Really? Sure. I know the integers to be infinite, without having counted them all up), and I cannot know more than the I.M.; therefore anything I know, the I.M. knows. You can think up variations as time and your own taste permits.

Now—enter the evil daemon.

Descartes, in his *Meditations on First Philosophy*, famously introduces the possibility that his ratiocinations are being systematically thrown off the rails by an “evil daemon” bent on confounding his thought. The E.D. makes Rene *think* he has a body, makes him *think* there is an external world, and so on, when in fact none of this is objectively so. (One of the many side-roads this leads us on: how can the E.D. be sure it doesn’t have its own E.D.?) This is sometimes called the “brain in a vat” scenario, invariably linked these days with *The Matrix* and its lamentable sequels.

Don’t be put off guard by the various pulp versions of this conundrum, though; the E.D. is epistemological acid. When much of Descartes’ thought has devolved into being of merely historical interest, this agent of radical skepticism will still be working to undermine our surety.

So, is the I.M. susceptible to the E.D.? Can even God be unsure as to whether He is really just a brain floating in a vat?

I would propose that the answer is yes—even an I.M. fails to achieve absolute certainty. For all it knows, that is, the I.M. may not be an I.M. at all.



To see why, suppose now that there is a finite mind--the F.M.--that is being misled by the E.D. to think itself an I.M. To the best of *its* knowledge, every possible true statement is contained propositionally inside itself, including the true statement that it contains all possible knowledge. However, the F.M. is wrong. The E.D. is only making it *think* that it knows all things, while at least one truth is escaping it: the true statement “the I.M. is, in fact, a F.M.”

Technically the F.M. need not even be finite; an infinite collection may fail to be exhaustive, as do the natural numbers. Very good; let it be infinite but non-exhaustive, endlessly thinking an unlimited number of truths but never noticing the missing one. The point is that exactly because the F.M. does not have access to that hidden truth, it cannot tell that its contents are not exhaustive. Nor does it have access to such true statements as “My thoughts only *seem* to be exhaustive.” Therefore it cannot distinguish itself from the true I.M.

Now you see the problem. The *true* I.M. is in exactly the same epistemological position. The I.M. believes itself to know all things, including the (seemingly) true proposition that it knows all things. As it happens, the I.M. is correct. And yet the I.M. cannot confirm that belief, as the F.M. draws the same conclusion, from the same data (the proposition “My thoughts only *seem* to be exhaustive” doesn’t occur in the true I.M. either). Thus the I.M. can’t be certain it isn’t the F.M. In figurative speech, even God couldn’t be sure that He was God.

The application of the E.D. to T.O.E.? I can think of a few. Clearly there’s a problem with the very concept of exhaustive, or absolute, knowledge. And it doesn’t look like a small one.

But first we’ll see what you have to say.


We Have Lift-Off (Planck & FQXi)
By ZEEYA MERALI • May. 22, 2009 @ 14:34 GMT

You might be wondering why nobody at FQXi was following last week’s successful launch of the Ariane 5 rocket carrying two new observatories: The Planck mission, which will scan the cosmic microwave background in unprecedented detail; and infrared telescope Herschel that will look for the faint emissions from objects at the edge of the solar system and from distant galaxies. Certainly the missions promise to uncover data that will help answer the sort of foundational questions that are this site’s bread and butter.

The reason, as some may have picked up, was that last Friday FQXi had a (re)launch of its very own, debuting a redesigned website. Many thanks to Christopher Gronbeck and Tien-Yi Lee for the new look. I should add that we didn’t deliberately set our launch date to match the European Space Agency’s in a subversive effort to steal their thunder; it was a coincidence on our part. (Whether ESA deliberately delayed their launch to coincide with ours, however, I cannot say...)

All this is leading up to me saying that, of course, FQXi researchers are thrilled about the prospects of Planck and Herschel. Well, I _say_ that, but a controversial physics birdie whispered in my ear last week that s/he thinks that Planck doesn’t actually have much to offer, and that all the good CMB data was already mined by WMAP. This physics birdie knows his/her stuff, and isn’t affiliated to either to either Planck (well, obviously) or WMAP. So is Planck worth the fuss? I’ll leave that to others who know more about CMB observations to argue over.

In Planck’s defense, I should point to a nice article that ran in Nature a few weeks ago that talked about what Planck might tell us about whether inflation happened or not, with comments from FQXi’s Andrei Linde. It follows earlier hints found in WMAP’s 3-year data that things might not all be smooth sailing for inflation. The excitement around those initial hints has since been dampened, but hasn’t died out completely, and the Nature piece re-analyses the story in light of forthcoming Planck data that might help pick inflation apart from the much more controversial cyclic universe model.

Anyway, back to the more optimistic line, FQXi grant-winner Alex Maloney, for example, hopes that the Planck observations will vindicate his attempts to find to a wavefunction of the universe, by treating the universe as a hologram. You can read more about his work in Anil Ananthaswamy’s article “The Holographic Universe.”

Maloney’s work hinges on the holographic principle, a trick physicists use to handle tough problems by recasting them as equivalent problems in a lower number of dimensions. He isn’t the only one trying to exploit this principle. Others include FQXi grant-winners Subir Sachdev (who wants to use the principle to work out whether string theory could have relevance to the real world, in particular to materials science) and Alex Vilenkin (who is using it to and take a census of all the universes in the multiverse).

So anyway, good luck to Planck, Herschel, and FQXi’s holographic physicists.

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