Hitchen vs. Galloway: The Jungle in the Rumble

From The Guardian (with a link to a video of the event at the bottom of the article, not to be watched while eating or shortly after having eaten):

“What had been billed as ‘the grapple in the Big Apple’ in the end owed more to pugilism than polemics, with jibes, like jabs, missing more often than they landed, and many a blow below the belt.

Hitchens berated Galloway for his ‘sinister piffle’, congratulating him on ‘being 100% consistent in [his] support for thugs and criminals’ and declaring: ‘The man’s search for a Fatherland knows no ends.’ Galloway branded Hitchens a hypocrite and ‘a jester at the court of the Bourbon Bushes’. Describing Hitchens’ journey from the left to the right, Galloway said: ‘What we have witnessed is something unique in natural history. It’s the first metamorphosis of a butterfly back into a slug.’ In the heat of battle the fact that butterflies come from caterpillars did not temper the applause from the audience, roughly two-thirds of whom backed Galloway.

Having both torched the moral high ground, they would both later claim it as their own. At one point Galloway told Hitchens ‘Your nose is growing,’ only to deride his opponent for his ‘cheap demagoguery’. Hitchens scolded the jeering audience for their ‘zoo-like noises’, only to say that Galloway’s ‘vile and cheap guttersnipe abuse is a disgrace’.

In a debate that drew as much from the culture of the playground as the traditions of parliament, no hyperbolic stone was left unturned.”

Or unthrown for that matter. 

Nazi Hunter Simon Wiesenthal Dies at 96

Adam Bernstein in the Washington Post:

Ph2005092000596Simon Wiesenthal, 96, the controversial Nazi hunter who pursued hundreds of war criminals after World War II and was central to preserving the memory of the Holocaust for more than half a century, died early today at his home in Vienna, Austria. He had a kidney ailment.

Called the “deputy for the dead” and “avenging archangel” of the Holocaust, Wiesenthal after the war created a repository of concentration camp testimonials and dossiers on Nazis at his Jewish Documentation Center. The information was used to help lawyers prosecute those responsible for some of the 20th century’s most abominable crimes.

Wiesenthal spoke of the horrors first-hand, having spent the war hovering near death in a series of labor and extermination camps. Nearly 90 members of his family perished.

More here.

Egypt’s Elections

Joshua Hammer & Christine Spolar in The New Republic:

…yet, for all its problems, the election may have created momentum for democratic reform that the Mubaraks will have trouble stopping. Cafés have been alive with talk of politics, and the strategies adopted by the pro-democracy forces–such as challenging the regime’s election commission for the right to place independent monitors in polling stations–were closely watched. Monitors ended up having to negotiate their way into the polls, but they were surprisingly successful in many instances. And they gained valuable tools for the next go-round. Ayman Nour–the charismatic 40-year-old former parliamentarian whose arrest earlier this year prompted protests from the Bush administration–came in second with 7 percent of the vote, thus emerging as the leader of the nascent opposition. Nour’s campaign was low-budget and wildly disorganized. But his message–he attacked ruling party corruption and called for a repeal of the repressive Emergency Laws, enacted after the 1981 assassination of Anwar Sadat–grew bolder as the weeks progressed. Equally important, the campaign changed public perceptions of Mubarak. “Before, Mubarak was seen as a God–detached, unreachable,” says Negad El Borai, a human rights attorney and member of a pro-democracy group that sought to monitor the presidential elections. “Now the God is being forced to travel to the provinces, asking people to give him their vote. It’s a sea change in Egyptian politics.”

More here.

Do You Know the Way to Dr. Dre?

From Casa del Ionesco:

What the world needs now: a Burt Bacharach/Dr. Dre collaboration?

from The Independent

Once the world’s smoothest crooner, Burt Bacharach is now collaborating with Dr. Dre and attacking President Bush. He tells John Walsh why he’s swapped easy-listening for tough-talking:
more

Good article but one minor quibble: Burt is the Sultan of Songwriters, not to mention the undisputed Emperor of Easy, but his crooning is only marginally smoother than the use of sandpaper as a facial exfoliant: that’s why Dionne, Dusty, Tom, Gene, Perry, Jack et alia were let loose on those melifluous melodies. Burt’s exquisitely sophisticated arrangements even made Cilla sound good, though they failed to elevate his own resolutely earthbound vocals. As a songwriter… Burt’s natural habitat is more Mount Olympus than Hasbrook Heights but as a crooner… hell, he’s just another Icarus in diving boots.

More here.

Second thoughts on leap seconds

From CNN:

The Royal Astronomical Society on Wednesday called for a public debate on the proposed abolition of leap seconds, a tiny end-of-year adjustment to keep clocks in synch with the earth’s rotation.

The International Telecommunications Union will meet in Geneva in November to debate a proposal to abolish leap seconds after 2007.

Mike Hapgood, secretary of the Royal Astronomical Society, said the debate has practical implications for computers, global positioning systems and for those who study phenomena — such as tides — that are related to the earth’s rotation.

There have been 21 leap seconds since they were introduced in 1972, and the next is planned for the end of 2005.

Dan Chiasson

Here Follows an Account of the Nature of Birds

Here Follows an Account of the Nature of Fish.
Here follows a description of an unknown town.
Here follows the phoenix-flight from human eyes.
Here follows the friendship fish and langouste.
All the marvels of erotic danger follow here.
Here follows the phone number of a dead person.
Here follows a game based on perfect information.
Five minutes have passed since I wrote this line.
I mistook my baby’s cry for the radiator hiss.
Here follows the address of a place to buy cocaine.
Big sadness come your way, sunrise, skyline.
Let’s do it some new way next time we try.
Do you have anything you can put inside me?
Here Follows an Account of the Nature of Birds.

from Dan Chiasson’s Five Poems at The Paris Review.

Sartre and Beauvoir

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Sartre and Beauvoir had met in Paris in 1929, when he was twenty-four, she was twenty-one, and both were studying for the agrégation, the competitive examination for a career in the French school system. Beauvoir was a handsome and stylish woman, and she had a boyfriend, René Maheu. (It was Maheu who gave her her permanent nickname, le Castor—the Beaver.) But she fell in love with Sartre, once she got over the physical impression he made. Sartre was about five feet tall, and he had lost almost all the sight in his right eye when he was three; he dressed in oversized clothes, with no sense of fashion; his skin and teeth suggested an indifference to hygiene. He had the kind of aggressive male ugliness that can be charismatic, and he wisely refrained from disguising it. He simply ignored his body. He was also smart, generous, agreeable, ambitious, ardent, and very funny. He liked to drink and talk all night, and so did she.

more from Louis Menand at the New Yorker here.

Chatting Up Cells: Nano reservoirs on a chip tell stem cells what to do

From Scientific American:Nano

Stem cells can transform into whatever cell the body tells them to. Unfortunately, scientists have yet to master that particular gift of gab. But investigators at Stanford University may soon crack the language with tiny “chat rooms” for stem cells. In their natural milieu, stem cells have a variety of neighbors that pass on chemical messages at exact spots at particular times in specific amounts to guide the cells’ development into a given cell type. In today’s laboratory, however, researchers often bathe the whole cell with chemicals–kind of like out-of-control beer keggers compared with the sophisticated cocktail parties the body normally throws for stem cells. To uncover the mostly unknown placement, timing and identity of the cues, Stanford materials scientist Nicholas A. Melosh and his colleagues are re-creating the niche where stem cells normally dwell. They are developing a microscopic lab on a silicon chip that surrounds a stem cell with as many as 1,000 cavities, each 500 nanometers wide.

More here.

Male weevils give females the gift of youth

From Nature:Weevil

Ever think your spouse is turning you grey before your time? Well things are very different for a beetle being studied by Swedish evolutionary biologists. They have found that some male bean weevils can slow down the ageing process in their mates simply by having sex with them. Female weevils (Acanthoscelides obtectus) live longer when mated with males that have been bred to reproduce later in life, report researchers at Uppsala University. By supplying a cocktail of age-defying chemicals with their sperm, the males stop their mates dying off before they have had the chance to produce a large family. “The males are promoting their own selfish interests by being the good guys in this case,” explains Göran Arnqvist, a member of the study team. “It benefits males if their mates live longer.”

More here.

Tuesday, September 20, 2005

Island Floating around the Island

2005_09_floating

Speaking of the James Cohan gallery (previous post), they are invloved, along with The Whitney and others, in finally realizing Robert Smithson’s dream of having a tugboat carry an island around the island of Manhattan. Links to various articles and so forth can be found here.

And here‘s something from New York Magazine:

New Yorkers enjoy the unexpected gesture, the extravagant folly, the existential leap. This fall, Minetta Brook (a nonprofit arts organization) and the Whitney Museum will realize a whimsical idea of this kind by the earthworks artist Robert Smithson. In a drawing made in 1970, three years before his death, Smithson conjured up a ‘floating island’ that would circle the fixed island of Manhattan like a slow-moving planet. Built on a barge and pulled by a tugboat, it consisted of a tailored landscape of rocks, trees, and pathways. It looked like something carved from Central Park.

Bill Owens

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Occupying the territory between Lee Friedlander’s formal elegance and Gregory Crewdson’s over-the-top American Gothic, Bill Owens has been using photography to pry into the American psyche for almost four decades. This show includes work from his best known series—”Suburbia,” 1972, “Our Kind of People,” 1976, “Working, I do it for the money,” 1978, and “Leisure,” 2004—as well as unpublished photographs from the late ‘60s that point toward Larry Clark’s vision of debauched American youth.

more from Artforum here.
a link to the James Cohan gallery where the Owens exhibit can be found is here.

Niebuhrism

Arthur Schlesinger, Jr., writes in this week’s NYTBR:

In the midst of this religious commotion, the name of the most influential American theologian of the 20th century rarely appears – Reinhold Niebuhr. It may be that most “people of faith” belong to the religious right, and Niebuhr was on secular issues a determined liberal.

Schlesinger asks if we are “Forgetting Reinhold Niebuhr.” As usual, on political issues my friend Alan Koenig already had a bead on this some time ago. Here’s an excerpt from his Beliver essay “Where are the Real Niebuhrians?”:

In noting America’s unease and odd naïveté in wielding power for universal ideals, Niebuhr cautioned that, “Consistent with the general liberal hope of redeeming history, the American Messianic dream is vague about the political or other power which would be required to subject all recalcitrant wills to the one will which is informed by the true vision.”

In the present circumstances, something about that seems awfully timely.

First View Of Many Neurons Processing Information In Living Brain

From Harvard Magazine:Neurons

Harvard Medical School researchers have applied a new microscopy technique in a living animal brain that for the first time reveals highly sophisticated time-lapse images of many neurons coordinating to produce complex patterns of activity. The approach will open up new avenues for analyzing neurodegenerative diseases and other aspects of the brain. “Put simply, this technique allows us to see the brain seeing,” said R. Clay Reid, HMS professor of neurobiology, a member of the HMS Systems Neuroscience initiative, and principal investigator on the project. “It’s an entirely new way of looking at brain function.”

The method, the first to track the responses of all the neurons in a visual circuit simultaneously, promises to rapidly advance our understanding of how the brain is wired for complex image processing. Lessons learned by studying the visual system may eventually apply to other brain functions like movement, thinking, and learning, as well as neurodegenerative diseases.

More here.

Almost Before We Spoke, We Swore

From The New York Times:Curse

Incensed by what it sees as a virtual pandemic of verbal vulgarity issuing from the diverse likes of Howard Stern, Bono of U2 and Robert Novak, the United States Senate is poised to consider a bill that would sharply increase the penalty for obscenity on the air. Yet researchers who study the evolution of language and the psychology of swearing say that they have no idea what mystic model of linguistic gentility the critics might have in mind. Cursing, they say, is a human universal. Young children will memorize the illicit inventory long before they can grasp its sense, said John McWhorter, a scholar of linguistics at the Manhattan Institute and the author of “The Power of Babel,” and literary giants have always constructed their art on its spine.

More here.

Monday, September 19, 2005

Selected Minor Works: Replacing William Safire

Justin E. H. Smith

William Safire’s recent retreat to half-time duties at the New York Times
may no doubt be taken as an indication that he is not long for this world.
I confess I cannot help but fantasize about the position this will open up,
not of course that of right-wing bloviator at the heart of the liberal media
establishment, but that of our nation’s leading language maven.  Give his
op-ed column to some cocky veteran of the Harvard Crimson.  I want ‘On
Language’.

This title, under Safire’s reign, has been something of a misnomer.  He
purports to write on language, but for the most part writes on a particular
language.  The language he writes on is also the language he writes in, and
it is, to be sure, a historically significant and widely spoken one.  But
language itself is one thing, languages are quite another.  Safire would
know this if he were willing to venture out a bit and consider a language,
such as French, that captures, in distinct terms, the distinct concepts of
language per se, on the one hand, and this or that language on the other.

Even if he were to concede that it’s not langage but this or that langue
that interests him, surely there are others besides English that would
warrant attention.  The Uralic family, for example, consisting in the Finno-
Ugric and Samoyed branches, has some interesting features.  Yurak, one of
its lesser children has ten distinct moods for its verbs: indicative,
narrative, potential, auditive, subjunctive, imperative, optative,
precative, obligative, and interrogative.  Yurak’s cousin Selkup attaches
conjugational suffixes to verbs to express different modes of action,
including the continuative suffix, the breviative, the frequentative, the
plurative, and the usitative.

It’s just a hunch, but I’m pretty sure Safire wouldn’t have a thing to say
about the usitative suffix.  And yet this is assuredly a bit of language,
employed competently by hunter-gatherers out in the tundra, and described
beautifully, with breathtakingly foreign extracts of written Selkup too
dense with diacritical marks to reproduce here, in Björn Collinder’s
magisterial Survey of the Uralic Languages (Stockholm, 1957).

But let us return to the Indo-European family.  If I were allowed to write
‘On Language’, I would devote much space to negation and to definite articles,
drawing rich examples for comparison from the Slavic, Romance, and Germanic
branches of this distinguished dynasty.

I would meditate on a curious parallel between the French split negation,
“ne…. pas” or “ne… rien”, and a certain vulgar means of denying in
English.  Consider the French for “I saw nothing”:  “Je n’ai vu rien.”
Consider, now, the structural similarity to this of the colloquial “I didn’t
see shit.”  I have no developed theory to offer, but it seems to me that
this counts as a split negation in English, and that ‘shit’ is doing exactly
the same work as the French ‘rien’.  That shit and nothing are substitutable
is a fact perhaps of interest to psychoanalysts as well as linguists.  Here
I’m only pointing it out.

I have more developed ideas about definite articles.  One thing that has
long troubled me is the existence of languages, such as Russian and Latin,
that can do entirely without them. I have seen some of Bertrand Russell’s
work on definite descriptions translated into Russian, and there the
translator was forced to simply retain the English article.  But one wonders
if the problem that concerned Russell would have come up at all if he had
been a monolingual Russophone.

The absence of ‘the’ in Russian troubled me greatly recently as I struggled
to translate Aleksandr Blok’s melancholy and Nietzschean poem about
Leningrad, the one that begins “Noch’, ulitsa, fonar’, apteka.”  Is he
writing about a night, a street, a lamp, and a pharmacy, or the night, the
street, the lamp, and the pharmacy?  Can this question even be answered?

In order to preserve the original Russian’s meter, I decided to leave out
the definite articles in the first stanza, and put them in in the repetition
of the same terms in the second stanza, thereby yielding the extra syllables
needed to make the English rendition flow.  Here is the result:

Night. Street. Lamp. Pharmacy.
Meaningless and murky light.
Live another quarter century.
It will be as now. No hope of flight.

You’ll die, you’ll begin again from the start.
Just as before, it will all repeat.
The night.  The canal’s icy ripple.
The pharmacy. The lamp. The street.

Now the question I’ve been unable to answer is whether the repeated use of
‘the’ at the end is poetic license on my part, or whether the original
Russian nouns entitled me to insert whatever articles I felt were needed,
and for whatever reason.  Again, they are there at the end, and not in the
beginning, only to preserve meter, and not because the meaning of the
Russian seems to require them more in the second stanza.  But are they truly
not there in the Russian, are they equally there and not there, or is there
simply no fact of the matter?

If Arthur O. Sulzberger is interested, I will be happy to meditate on this
further, as on related questions, in the Sunday Times.  It is much more
likely, of course, that the same young cock from the Crimson who got the op-
ed column, or perhaps his roommate, will get the language column as well,
and he will expatiate on the origins of words like ‘synergy’ and approvingly
rehash the witticisms of Winston Churchill.

Having come to terms with this harsh reality, I look forward to offering my
thoughts on language, as well as art and culture, to you, the good readers
of 3 Quarks Daily, every third Monday in my new column, ‘Selected Minor
Works’.

Grab Bag: Bite Your Tongue, Movies Turn Dumb

In “Summer Fading, Hollywood Sees Fizzle,” published in the New York Times on August 24, Sharon Waxman discussed the decline of ticket sales in the context not of a shifting economy or social landscape but instead of the increasingly lacking quality of mainstream movies. The piece was a helpful reminder to discontented viewers that they are not alone. This may seem silly: many of us hear our friends bitching and moaning about movies all the time, but we also hear our friends bitching and moaning about the current state of the government, about obesity in the US, about cultural appropriation, about any number of liberal topics met only with clichéd observations and statements of the obvious. But while our government continues it spiral downward with increasing momentum, while obesity climbs, and while kaballah water is sold at Wal-Mart, Waxman’s presentation of a panicked film industry provides some hope that perhaps America is finally taking a stand against the monolithic empire of Hollywood. It is no longer the white elephant, but an issue in which the industry must respond to money, the thing that whispers throughout its collective home with deadly quiet and unnerving interminability.

That a slow in the flow of money has worried the industry of course comes as no surprise, but what seems to be happening is that excuses are wearing thin. No longer are studios entirely attributing dropping ticket sales to dvds, tv, home entertainment, bad weather, good weather, higher gas prices et cetera. Instead, the industry appears to be finally looking inward to reassess its product.

New Hollywood movies seem to suffer from several problems, some superficial and some more fundamental. The superficial problems lie in the changing conventions of the industry. While conventional formulas still shape movies, they are increasingly muddled and—oddly—simultaneously too specific. The crossbreeding of genres has spread conventions so thin that meanings can be confused or even contradictory. For example: Mr. and Mrs. Smith as an action movie sets up, plays out, and resolves glossy and unemotional violence in a typically Hollywood way, with predictable style and visual effects. As a romantic comedy too, the film uses a well-worn and well-known vehicle, a couple is living a static and cold life that is re-impassioned through some kind of hardship or trauma. The blending of these two systems, however, resulted in sloppiness all around: the movie didn’t have to have well choreographed or stimulating action sequences because of the romantic subplot while the romance didn’t have to be explained or even make sense because of the action.

Similarly, a movie like the Fantastic Four was enough of a comedy that its cartoonish CGI wasn’t as glaringly offensive and yet it was still at its core an action movie and so its comic simplicity was permissible. These constant justifications leave most mainstream movies that try and blend genre more a hodge-podge than an interweaving and we are constantly distracted from our questioning through the inclusion of more disconnected plot material.

My constant and first complaint when leaving new blockbusters recently has been about questionable logic. I am perfectly happy watching movies that are silly, ridiculous, fantastical, and minimal as long as there is some internal logic and consistency. New movies, though, are breaking standards of providing background information and causality that fifty years ago would border on avant-garde. But in today’s movies there are no ends to this choice. There is no refutation or exploration of narrative convention, no tongue-in-cheek homages or implicit criticisms in the oftentimes bizarre flow of plot information. Even in a pseudo-documentary like March of the Penguins, so many details of the story were left out, so many questions went unanswered, and so much of the film relied on picturesque imagery that I left the theater more confused than when I arrived about the subject. Of a documentary.

Film has successfully, since its beginnings, built a language around itself through which it expresses a kind of reality that the spectator not only observes, but engages with as well. We are asked to accept non-realistic sound and image as realistic, and we do so because we are so used to it. Editing is a typical example: while we don’t see the world through a series of edits, we never question this basic mechanism when watching a movie. Space is disrupted, it is extended and contracted, but we are never disoriented while watching it because we are a part of a larger cinematic reality, which we perceive differently. There are countless other examples of this same operation in film—from framing to sound use to camera angle and color manipulation—that all together build a basic vocabulary of the medium.

Genre takes the notion of vocabulary and hones it so precisely that it eventually functions as an equation into which each film provides variables, essentially introducing to the vocabulary a syntax that organizes the smaller formula-parts. Within this tight-knit code meaning is created through small changes. Take a standard horror plot but instead of the blob make the bad guy a space-monster, and suddenly the allegory shifts from fear of consumption to one of xenophobia. This same plug-in method exists in most genres, for example the feminist—albeit old-fashioned—western 40 Guns or the homosexual twist of the melodrama Far From Heaven, both of which heavily rely on the spectator to know the formula and thus understand the significant changes.

Over the course of the last century then, the silver medium has developed specific genres and specific stylistic conventions that have, through their repetition, crafted the ideal audience. New blockbusters, though, are losing this consistency by changing this vocabulary, partially by tying it in more closely to television. The difference between the two can be difficult to isolate, but it certainly has something to do with the cadences of dialogue and comic delivery, the “situational” humor. Likewise though, tv has become more cinematic, especially seen in the HBO series shows such as the Sopranos and Entourage. Whatever the difference, going to the movies has begun to feel—to those who have experienced it—like watching television for the first time in months and months: you are utterly disoriented in a world that you know you should “get,” in which every allusion and every reference soars above your head. Unlike television, however, film is not serial (sequels excluded), and the same modes of storytelling cannot be adapted to both.

Ultimately, it seems as though the language of cinema has finally begun to get ahead of itself, that the very formulas it established have been abstracted to a point that is so basic that the spectator is either bored by it or, in my case, dumbfounded by it. Film has almost followed the same, albeit more condensed, trajectory of other visual arts: from a time of documentary realism to increased experimentation and ultimately visual language built upon a foundation of conventional symbols. This language, however, has begun to grow incomprehensible to the very audience whose continued acceptance of it allowed its conception in the first place. The industry then has to take a more theoretical approach to the problem and figure out a way to re-connect to the audience not through the stories it tells, but by the way in which it expresses those stories. Generic and visual conventions need to return to an earlier state in which their very clarity generated interest, in which stories were easier to understand and in which language was not always foreign.

Monday Musing: General Relativity, Very Plainly

[NOTE: Since I wrote and published this essay last night, I have received a private email from Sean Carroll, who is the author of an excellent book on general relativity, as well as a comment on this post from Daryl McCullough, both pointing out the same error I made: I had said, as do many physics textbooks, that special relativity applies only to unaccelerated inertial frames, while general relativity applies to accelerated frames as well. This is not really true, and I am very grateful to both of them for pointing this out. With his permission, I have added Sean’s email to me as a comment to this post, and I have corrected the error by removing the offending sentences.]

In June of this year, to commemorate the 100th anniversary of the publication of Einstein’s original paper on special relativity, I wrote a Monday Musing column in which I attempted to explain some of the more salient aspects of that theory. In a comment on that post, Andrew wrote: “I loved the explanation. I hope you don’t wait until the anniversary of general relativity to write a short essay that will plainly explain that theory.” Thanks, Andrew. The rest of you must now pay the price for Andrew’s flattery: I will attempt a brief, intuitive explanation of some of the well-known results of general relativity today. Before I do that, however, a caveat: the mathematics of general relativity is very advanced and well beyond my own rather basic knowledge. Indeed, Einstein himself needed help from professional mathematicians in formulating some of it, and well after general relativity was published (in 1915) some of the greatest mathematicians of the twentieth century (such as Kurt Gödel) continued to work on its mathematics, clarifying and providing stronger foundations for it. What this means is, my explication here will essentially not be mathematical, which it was in the case of special relativity. Instead, I want to use some of the concepts I introduced in explaining special relativity, and extend some of the intuitions gathered there, just as Einstein himself did in coming up with the general theory. Though my aims are more modest this time, I strongly urge you to read and understand the column on special relativity before you read the rest of this column. The SR column can be found here.

Before anything else, I would like to just make clear some basics like what acceleration is: it is a change in velocity. What is velocity? Velocity is a vector, which means that it is a quantity that has a direction associated with it. The other thing (besides direction) that specifies a velocity is speed. I hope we all know what speed is. So, there are two ways that the velocity of an object can change: 1) change in the object’s speed, and 2) change in the object’s direction of motion. These are the two ways that an object can accelerate. (In math, deceleration is just negative acceleration.) This means that an object whose speed is increasing or decreasing is said to be accelerating, but so is an object traveling in a circle with constant speed, for example, because its direction (the other aspect of velocity) is changing at any given instant.

Get ready because I’m just going to give it to you straight: the fundamental insight of GR is that acceleration is indistinguishable from gravity. (Technically, this is only true locally, as physicists would say, but we won’t get into that here.) Out of this amazing notion come various aspects of GR that most of us have probably heard about: that gravity bends light; that the stronger gravity is, the more time slows down; that space is curved. The rest of this essay will give somewhat simplified explanations of how this is so.

THE PRINCIPLE OF EQUIVALENCE

Just as in special relativity no experiment that we could possibly perform inside a uniformly moving spaceship (with no windows) could possibly tell us whether we were moving or at rest, in general relativity, no experiment we can possibly perform inside the spaceship can ever tell us whether we are 1) accelerating, or 2) in a gravitational field. In other words, the effects of gravity in a spaceship sitting still on the surface of the Earth are exactly the same as those of being in an accelerating spaceship far from any gravitational forces. Yet another, more technical, way of saying this would be that observations made in an accelerating reference frame are indistinguishable from observations made in a classical Newtonian gravitational field. This is the principle of equivalence, and it is the heart of general relativity. While this may seem unintuitive at first, it is not so hard to imagine and get a grip on. Look at the spaceship shown in Fig. 1 (in the next section, below) and imagine that you are standing on its floor while it is standing upright on the surface of Earth, on the launch pad at Cape Kennedy, say. You would be pressed against the floor by gravity, just as you are when standing anywhere else, like on the street. If you stood on a weighing scale, it would register your weight. Now imagine that you are in deep space in the same ship, far from any planets, stars, or other masses, so that there is no gravity acting on you or the spaceship. If the spaceship were accelerating forward (the direction which is up in Fig. 1), you would be pressed against the floor, just as when an airplane accelerates quite fast down the runway on its takeoff roll, you are pressed in the opposite direction against your the back of your seat. If the acceleration were exactly fast enough, you would be pressed against the floor of the spaceship with the same force as your weight, and at this rate of acceleration, if you stood on a weighing scale, it would again register your weight. You would be unable to tell whether you were accelerating in deep space or standing still on the surface of Earth. (You could perform all of Galileo’s experiments inside the spaceship, dropping objects, rolling them down inclined planes, etc., and they would give the same results as here on Earth.) Are you with me? What I am saying is, for a gravitational field of a given strength in a given direction (like that at Earth’s surface toward its center), there is a corresponding rate of acceleration in the opposite direction which is indistinguishable from it.

I am afraid of losing some people here, so let me pump your intuition with a few examples. Have you ever been on one of those rides in an amusement park (the one I went to was called the Devil’s Hole) where you stand in a circular room against the wall, then after the room starts spinning quite rapidly, you are pressed strongly against the wall and then the floor drops away? It can be scary, but is safe because you are accelerating (moving in a circle) and this presses you to the wall just as gravity would if you turned the whole circular room on its side (like a Ferris wheel) and lay on the side of it which is touching the ground. Most gravity defying stunts, like motorcyclists riding inside a wire cage in the shape of a sphere, rely on the effects of acceleration to cancel gravity. You’ve probably seen astronauts on TV training for weightless environments inside aircraft where they are floating about. This also exploits the principle of equivalence: if the plane accelerates downwards at the same rate as a freely falling object would, this will produce what could be described as an upward gravitational force inside the plane, and this cancels gravity. Of course, from an outside perspective, looking through the plane windows, it just seems that the plane and the people in it are both falling at the same rate, which is why they seem to be floating inside it. But inside the plane, if you have no windows, there is no way to tell whether you are far away from any gravitational field, or simply accelerating in its direction. All this really should become quite clear if you think about it for a bit. Reread the last couple of paragraphs if you have to.

BENDING OF LIGHT BY GRAVITY

Rockets_copy_2Consider the leftmost three drawings of the spaceship in Fig. 1. They show the spaceship accelerating upward. Remember, this does not mean that it is moving upward with a steady speed. It means that it is getting faster and faster each instant. In other words, its speed is increasing. Now we have an object, say a ball, which is moving at a steady (fixed) speed across the path of the spaceship from left to right in a straight-line path perpendicular to the direction the spaceship is moving and accelerating in (up). Suppose, further, that there is a little hole in the spaceship just where the ball would strike the exterior left wall of the spaceship, which allows the ball to enter the spaceship without ever touching any part of it. Imagine that the spaceship is made of glass and is transparent, so you can see what happens inside. If you are standing outside the spaceship, what you will see is what is shown in the leftmost three drawings of the spaceship in Fig. 1, i.e., the ball will continue in a straight line on its previous path (shown in the figure as a dotted line), while the spaceship accelerates up around it (while the ball is inside the ship). Here’s the weird part: now imagine yourself standing still on the floor of the spaceship as it accelerates upward. You experience gravity which presses you to the floor, as described above. Now, you see the ball enter from the window in the left wall, and what you see is that it follows a parabolic arc down and hits the opposite wall much lower than the height at which it entered (shown in the rightmost drawing of Fig. 1) just as it would because of gravity if the spaceship were standing on the launchpad at Cape Kennedy and someone threw a ball in horizontally through the window. Do you see? One man’s acceleration is another man’s gravity!

You can probably guess what’s coming next: now imagine the the ball is replaced with a ray of light. Exactly the same thing will happen to it. The light will follow a parabolic arc downward and hit the opposite wall below the height at which it entered the spaceship, when seen by the person inside. The reason that you normally don’t see light bending in any spaceships is that light travels so fast. In the billionths of a second that light takes to get from one wall to the other, the spaceship doesn’t move up much (maybe billionths of an inch) because it is moving much slower than light moves. This small a deflection is impossible to measure. (This is just as you don’t see a bullet fired horizontally bending down much over a short distance, even though it is following a downward parabolic path to the ground. And light is a lot faster than bullets.) This bending of light must be true as long as we assume the principle of equivalence to be true, because if it weren’t, we could then perform optical experiments on the ship to decide whether we are in an accelerating frame or a gravitational field. This is forbidden by the principle of equivalence. And since we now see that light will bend in an accelerating spaceship (seen by someone in the ship) and since we also know that the person in the ship by definition has no way of knowing whether she is accelerating or in a gravitational field, light must also bend in a gravitational field. (Otherwise the person would know she is accelerating.) It’s really that simple!

The most famous experiment which confirmed the correctness of GR and made Einstein world famous overnight, was the observation of the bending of starlight by the Sun’s gravity in 1919, which I mentioned briefly in my June SR column. Also, in case you are wondering why light is bent by gravity even though photons have no mass at rest, it is because light is a form of energy, and as we know from special relativity, energy is equivalent to inertial mass according to E = mc2. All energy gravitates.

GRAVITATIONAL TIME DILATION

Circle_1_copy_3This time, let’s consider what happens with a rotational motion. Look at Fig. 2. It shows a huge disk. Imagine that we put two clocks on the disk: one at the center at point A, and one at the edge at point B. Also put a clock at point C, which is on still ground some distance from the disk. Now imagine that the disk starts rotating very fast as shown by the arrow. Now we know that the clocks at points A and C are not moving with respect to each other, so they will read the same time. But we also know that clock at B is moving with respect to the ground, and by the principles of special relativity must be running slower than C. And since C must be running at the same rate as A (they are not in motion relative to one another), B must also be slower than A. This will be true for an observer at C on the ground as well as at A on the disk, but their interpretations of why the clock on the edge at B is slower will be different: for the ground observer at C, the clock at B is in motion, which is what slows it down. For the observer at A, however, there is no motion, only a centripetal acceleration toward the center of the disc, and it is this acceleration which accounts for the slowing down of the clock. The further A moves toward the edge, the stronger the centrifugal force (and the centripetal acceleration), and the slower the clock he has runs. Since acceleration is indistinguishable from gravity (A has no idea if he tends to experience a force toward the outside of the disk because the disk is rotating, or whether the disk is still and he is in a gravitational field), clocks must also slow down in gravitational fields. This slowing down of time by gravity has been confirmed by experiments to a very high precision.

THE CURVATURE OF SPACE

We just looked at time. Let’s see what happens with space. Take the same disk from Fig. 2 and replace clock B with a ruler. Place the ruler at B so that it is tangent to the disk. For the same special relativistic reasons that the clock at B will run slower, the ruler at B will be contracted in length. Use another ruler to measure the radius from A to B. since the rotational motion on the disk is always perpendicular to the radius, this will be unaffected by motion. Since only the ruler at B is affected, if that ruler is used to measure the circumference of the disk, the ratio of that measured circumference and the measured diameter will not be Pi (3.1415926…), but a smaller number, depending on the rate of rotation of the disk. This is a property and an indication of a curved surface. But the rotation (accelerated motion) is equivalent to a gravitational field as we have already seen, so we can say that gravity causes space to become curved.

There is much, much, much, more to this grand theory, and I have but drawn a crude cartoon of it here in the small hope that I might impart a bit of its flavor, and indicate the direction in which Einstein moved after publishing special relativity in 1905. Andrew, this is the best I can do.

Thanks to Margit Oberrauch for doing the illustrations.

Have a good week!

My other recent Monday Musings:
Regarding Regret
Three Dreams, Three Athletes
Rocket Man
Francis Crick’s Beautiful Mistake
The Man With Qualities
Special Relativity Turns 100
Vladimir Nabokov, Lepidopterist
Stevinus, Galileo, and Thought Experiments
Cake Theory and Sri Lanka’s President

Sunday, September 18, 2005

Afghanistan: A woman’s Place

Aryn Baker in Time Magazine:

Nearly four years after the U.S.-led coalition overthrew the Taliban, Afghanistan is still stumbling on the path to peace and stability. The country is nowhere near as violent as it was before; it has a new constitution that enables the establishment of civil institutions like an independent judiciary; and foreign investment is trickling in. Outside the capital Kabul, however, much of the hinterland remains poor and lawless, often controlled by rival warlords and drug barons who do not answer to the central authorities. The presidential election that Hamid Karzai won last year should have given the divided country a unifying leader. But Karzai has been hamstrung by the lack of a parliament or local government bodies, and many Afghans derisively call him “mayor of Kabul.”

Afghanistan will only become a true democracy when citizens can turn for help to locally elected leaders, rather than armed warlords. That’s why this week’s polls are potentially so important.

More here.