Thursday, June 30, 2005
Problems with the blog template were growing out of control, so I just went and got a new one. This one is based on one by Jason Shellen. Let me know if there are problems.
Remember when we talked about Chief Illiniwek, the University of Illinois mascot? The Chief's supporters claim that it's really a gesture of respect to have a student dress up in war paint and do silly dances -- a matter of honoring the bravery of Native Americans. Notice any similarity to the explanations coming from Mexico these days?
Wednesday, June 29, 2005
The new issue of symmetry magazine has hit the virtual newsstands (and the real newsstands, for all I know). Much good stuff as usual, including a deconstruction of the CMS experiment at CERN that I mentioned a few weeks ago. There is also an interview with new Fermilab director Pier Oddone, who quotes with approval the motto of Chicago architect and planner Daniel Burnham: "Make no little plans; they have no magic to stir men's blood." Apparently the 21st-century realization of this advice is to build a linear collider.
There is also a tiny contribution by me: extra dimensions in 60 seconds. Okay, so I had to gloss over some details. Even better, you can learn that Alan Guth's real claim to fame is not that "inflation" stuff -- it's that he is the only person to have written papers with both me and Lisa Randall.
Monday, June 20, 2005
Love advice from Saddam
Only fifteen minutes into my vacation, but I can hardly resist posting this.
Saddam learned the names of the GIs guarding him, was interested in the details of their lives, which they were not supposed to discuss, and sometimes offered fatherly advice. They conversed in English.(Mark my words, there will soon be a recognized psychiatric diagnosis for the syndrome which forces people to think "blog this" whenever the read something interesting.)
Much as it pains me, I'm going to go on what bloggers typically call an "hiatus," although I prefer the term "vacation." From blogging, anyway. Not that I'm going on any sort of real vacation, but I'll be traveling like crazy for the next month or two, and between that and the rest of my life I don't want to feel like a bad person if I don't blog every day.
I'll likely still post some stuff, albeit very rarely, for the next few weeks. After that, storm back re-invigorated and saucier than ever.
Friday, June 17, 2005
It's tough sometimes, being a middle-class straight white American male. I mean, we rule the world, and it's really hard to get anyone to feel sorry for us. We have feelings too, you know.
So it's good to know that, as an atheist, I'm a member of an honest-to-God persecuted minority. The latest example comes from Brooklyn College, where Timothy Shortell was forced to decline the position of chair of the Sociology Department after the tabloids discovered that he was an atheist. (Don't they realize how hard it is to get good department chairs?) Read the story at Majikthise and Feministe. The real source of trouble was an essay on anti-naturals.org, in which Shortell had not-so-nice things to say about religious morality. As Lindsay says,
Jokes aside, this is a completely inexusable violation of academic freedom, not to mention religious freedom. The administrators at CUNY (of which Brooklyn College is a part) should be ashamed of themselves.
Oscar Brown Jr.
It was just in April that I posted about Oscar Brown Jr, the soulful singer and songwriter who was also something of a social activist. Somehow I missed the news that he just passed away on May 31st. On the day I wrote about him, he was giving a show here in Chicago, his hometown; now I'll never have then chance to see him perform live. A service will be held on June 24.
Friday Random Ten with a twist: use your iPod to divine the future, by using the first ten songs to appear in a random playlist as Tarot cards in the Celtic Cross spread. Full explanation, including a key to the positions, here.
This week, let's ask a specific question: "Will the Democrats recapture the White House in 2008?" The songs say:
But the auguries for the future are more ambiguous. The Future speaks of heartache. The Inside, referring to our hopes, fears, and expectations, seems to think we'll get lucky. And the Outcome, wrapping up the whole story, is a Sex Mob tune.
Is it possible that Rep. Sensenbrenner will succeed at repealing the 22nd Amendment, and (to his horror) our next President will be -- Bill Clinton?
Thursday, June 16, 2005
How to ask the government for money for science
David Appell links to a powerpoint presentation by Joel Parriott, a self-described "worker bee" (really, Science Program Examiner) at the Office of Management and the Budget. Parriott, who received a PhD in astrophysics from Michigan, is trying to explain to scientists how they are viewed by the OMB when they come to ask for money. The interesting slides are where he explains the "Ethos and Mythos" of each community, and how scientists can most effectively make their case (edited slightly for clarity).
Wednesday, June 15, 2005
Update: Well, that was fast. Before I even got the post published, word is out that Mukhtaran Bibi may have been released! Who knows exactly what prompted the decision, but perhaps a well-timed blog campaign actually had some effect. On the other hand, it may just be a sham, as Kristof suggests (via Majikthise) -- so it's worth keeping the pressure on.
Update again (6/16): Apparently, she is still not free to travel. Perhaps unsurprising to see the US State Department joining in the "soothing" but misleading public statements.
Ezra Klein points to a post by Tom Watson about the arrest of Mukhtaran Bibi. Nicholas Kristof tells the backstory:
Last fall I wrote about Mukhtaran Bibi, a woman who was sentenced by a tribal council in Pakistan to be gang-raped because of an infraction supposedly committed by her brother. Four men raped Ms. Mukhtaran, then village leaders forced her to walk home nearly naked in front of a jeering crowd of 300.But then, Mukhtaran made plans to visit the U.S. Presumably she would tell people about some of the less pleasant aspects of the current situation in Pakistan. As Ezra explains:
Pervez Musharraf, our erstwhile ally in the War on Terror, couldn't have that. Mukhtaran Bibi was put under house arrest last Thursday. When she tried to walk out, police pointed guns at her. When she tried to make calls, they snipped the landline. When she moved to the cell, they took her to Islamabad and put her in prison. Then, for good measure, they released her rapists -- a warning shot.As good a reason as I've ever seen to bring political pressure to bear on a repressive government. Tom Watson suggests that everyone write to Pakistani officials to express their outrage, and has collected the relevant email addresses:
The 30th edition of Tangled Bank, the carnival of science-oriented blog posts, is now up at The Geomblog. I didn't submit anything, but Suresh has noticed that the squishy sciences tend to be over-represented in these carnivals, so he decided to take the initiative and include pointers to some interesting physics and math posts. So my entry on the arrow of time was included, as well as a nice older post by John Baez on topology and a newer one by Cosma Shalizi on Gödel's theorem.
Tuesday, June 14, 2005
Profiles in courage
The US Senate passed a resolution, sponsored by Mary Landrieu and George Allen, that officially apologized to lynching victims for the Senate's failure to condemn lynching several times in the 19th and 20th centuries. Not a difficult position to get behind, really. Except that it was passed by voice vote, rather than by a roll call, because several Senators would not support the resolution.
So, who are the Senators who bravely hold the pro-lynching position? Unfortunately it will probably be impossible to ever know for sure, unless the Senators themselves tell us. Not only was their a voice vote, but it's possible to add your name as a co-sponsor of a Senate resolution even after it's already been passed. From Kos, here's the list of non-sponsors:
Lamar Alexander (R-TN)Via Atrios, Chris Geidner and Americablog are trying to figure out which of these non-sponsors were actively against the resolution. Any Senator who ends up not being a sponsor of a resolution like this should be ashamed of themselves.
Update 6/15: Several more Senators have now co-sponsored: Bond, Bunning, Burns, Chambliss, Conrad, Murkowski, and Voinovich.. Their names have been stricken out above. However, Chris Geidner has called all of the Senators' offices, and has been told by the offices of Sens. Alexander, Bennett, Cornyn, Grassley, Gregg, and Shelby that they support the resolution.
Update 6/17: Crapo, Grassley, and Hatch have now co-sponsored.
Via Deepen the Mystery, a photo essay from Time magazine about a Muslim high school right here in Illinois. Once they pass sixth grade, boys and girls play separately, and must wear the school uniform.
Talk about your throwback jerseys. I wonder what would happen if one of the students showed up at school with ERVING 32 on the back of their uniform, sporting a giant Afro.
Monday, June 13, 2005
The important shit
Remember the Miller Lite catfight ads? Two attractive and impossibly buxom young women are enjoying lunch and enter into the venerable "Tastes Great"/"Less Filling" argument. Except that, unlike John Madden and Bob Uecker, the women are soon tumbling into a fountain and ripping each others' clothes off, as the camera scans over their bodies. We then cut to two guys inside a bar, saying stuff like "Yeah, that would be a great ad! I would definitely buy whatever they were selling!" We then pan to the two women sitting next to them, also very attractive but not artificially enhanced, who are looking at their companions with undisguised contempt.
I liked those ads. They were clever and funny, and succeeded in having it both ways -- appealing to cheesecake instincts while parodying them at the same time. And unmistakably commenting on the cluelessness of guys in general, who would blithely ignore the gorgeous real women sitting next to them in order to indulge in an artificially-enhanced fantasy.
However, things aren't so simple. The attitudes that the ads were parodying really do exist. We breathe a cultural atmosphere in which women are often put into the role of objects to be manipulated for the sexual gratification of men, to the detriment of their status as equal persons. The battle to overcome these attitudes has been fought by feminists for generations, but is a long way from being won. To a lot of people, this kind of "soft" issue is unimportant, and detracts from the "hard" issues (e.g. equal pay for equal work) that women should be fighting for. But this soft/hard distinction isn't nearly so clear-cut as we might be tempted to believe. The reasons why women don't get equal pay for equal work ultimately come down to how men and women are perceived by the people in power who set the salaries, and these perceptions are manifestly shaped by the cultural messages that are beamed at us from every direction. Fighting to spread women's suffrage through the world and to preserve the right to an abortion is undoubtedly important, but so is the battle to use inclusive language or to allow women to keep their names when they get married. Ideas matter. Some of my friends have joked that the Larry Summers flap was the best thing that ever happened to women in science, since it jolted universities into taking the problem seriously, but that's just wrong -- thousands of female high-school and college students have now heard that the President of Harvard thinks they don't have the mental capacities to be scientists, and it will take years to undo that damage. To change the world, you have to change how people think about it.
I don't believe that the Miller Lite ads are the best target for a feminist critique; we are surrounded by images of objectified women's sexuality being deployed to sell products or ideas, without any ironic intent whatsoever, and I don't think that much damage is done by this kind of over-the-top parody. Nevertheless, I am certainly sympathetic to people who feel otherwise. I take very seriously the possibility that actual women might know better than I do how it feels to be bombarded by this kind of imagery on a daily basis. So, for example, if I started playing the ad on my website and I received complaints from people who were offended, I wouldn't hesitate to take it down. It's just not such a big deal, much more a matter of simple politeness than an esoteric point of feminist theory. If I'm serving lamb chops at a dinner party, and I learn that one my guests is a vegetarian, I would find something else to serve them, regardless of whether I agreed with their ethical reasons for not eating meat.
Fast-forward to the present day. To plug the reality TV series "The Real Gilligan's Island," TBS has made it's own catfight ad, featuring impossibly buxom avatars of Mary Ann and Ginger engaging in a pie fight (left). On every level, this ad isn't nearly as good as the Miller Lite ads; it's not very well produced, nor is there any ironic framing story. Basically an uninspired effort.
But someone working for the ad agency had two strokes of genius -- first, advertise for the ad itself, in a sort of meta-campaign (this is actually becoming pretty common, so not too much genius there). But second and more importantly, carry out the meta-campaign via blog ads on liberal websites like Daily Kos. I am presuming this was genius rather than just dumb luck, but it was startlingly effective in stirring up controversy, which undoubtedly got the ad much more attention than it would otherwise have received. Some people were amused by the ad, but others complained that it was demeaning to women. On a website purportedly devoted to championing liberal ideals of equality for all, perhaps it isn't perfectly appropriate to feature an ad that treats women like objects.
Again, I don't personally feel that an ad like this is the most effective target for our approbation. You don't have to look very hard on conservative websites to find similar ads that use women's bodies to sell stuff without any trace of irony, such as the ad on the right that you can find at Power Line. But once again, I'm also sympathetic. The standards are different, as they should be, for our rivals than they are for our friends. If a substantial fraction of the people I claim to be fighting for are made uncomfortable by an ad like that, it wouldn't seem to be that hard a decision just to remove it, and perhaps begin a discussion about the principles involved. No matter how committed we may be, we always have something to learn.
This is not the course that Kos chose to take. Here is his response to the flap.
Whatever. Feel free to be offended. I find such humorless, knee-jerk reactions, to be tedious at best, sanctimonious and arrogant at worst. I don't care for such sanctimony from Joe Lieberman, I don't care for it from anyone else. Some people find such content offensive. Some people find it arousing. Some people find it funny. To each his or her own.This comment falls somewhat short of perfectly sympathetic and open-minded. Indeed, it seems really dumb, which is what I don't get. Kos is a professional political consultant. Is this the kind of advice he gives his clients? That when some of their constituents complain about something that is important to them, they should be told to feel free to storm off?
The ad itself generated a tiny amount of grumbling, but Kos's response set off a firestorm, as it should have. See comments at Shakespeare's Sister (who has been singled out as the reason why Democrats can't win), Feministe, Pandagon, Bitch, PhD, Echidne of the Snakes, Creek Running North, Big Brass Blog, and Media Girl, as well as about 10,000 other places. There is also an interesting analysis of the comments at Kos by Sarah at Sampo, and some folks have started an entire new blog, Women Kossaks, to discuss these issues.
There are two things going on in Kos's response, both of which are unfortunate. One is that he obviously just doesn't think that women's feelings about these issues are all that important. It is always the case that sub-groups of large political movements will complain about being taken for granted, but this is a pretty clear example of where it's really true. Kos himself would obviously disagree; his attitude is that women's interests are best served by getting Democrats into power, and that goal is not helped by getting distracted by pie fights. He has a series of posts up (one, two, three) in which he tries to elaborate on the "core values" of the Democratic party -- as distinguished from those single-issue "special interests" that threaten to obscure the more important goals. This is by no means a crazy attitude, in fact there is a lot of truth to it. But Kos's stubborn tone-deafness about women's issues reveals an underlying cluelessness -- he doesn't come close to appreciating how important some of these issues are to women (who comprise, after all, well over half of Democratic voters), and how important they should therefore be to Democrats.
In a perfect world, where men and women were actually treated equally, something like the TBS ad would be completely harmless. The non-perfect world in which we actually live is a different story. (One indication of the fact that the world has not achieved perfect gender equity is the paucity of ads featuring oil-wrestling matches between hunky men in Speedos. Not, I expect, that such imagery would be very attractive to many people of either sex.) We can argue about the particular details, but it is by no means crazy to suggest that overcoming images like those in the pie fight is a crucial step in leveling the playing field between men and women -- which is, everyone would agree, the important shit.
The other unfortunate thing, which others have commented on, is the underlying anti-intellectual tone of the whole discussion, as exemplified by the "women's studies set" crack (for which he later semi-apologized). There is some feeling of uneasy co-existence between the "activist" and "academic" branches of modern liberalism, and these "soft" feminist issues are one of the points of major discomfort. People who are in the trenches working hard to advance progressive causes don't like to hear some intellectual telling them that even they are not quite as liberal and egalitarian as they would like to think. (It is left as an exercise for the reader to figure out how this kind of macho defensiveness aligns with stereotypical male/female attitudes.) And, goodness knows, people sitting in ivory towers thinking about cultural hegemony might not be the best guide to practical action.
But that's exactly the point -- both "sides" of the academic/activist split have a lot to learn from each other. I remember a lecture by Cornel West, where he chastised some of his liberal white friends who were convinced that they had personally overcome any hint of racism -- "I still am discovering racist attitudes lurking in my own thoughts, so I know that my white brothers have a way to go themselves." The problem was never really the stupid pie fight ad, it was the idea that complaining about the ad was somehow petty and illegitimate. It's great when men are committed to greater equality for women, but frustrating when they are convinced that they know all the answers and end up sounding patronizing and clueless, rather than sincerely listening to what actual women have to say. (Okay, that's a completely trite observation that applies to any group speaking about any other group. But "Patronizing and Clueless" would make a great name for a band.)
Thanks to Shakespeare's Sister for nudging me and others to talk about this. Go wish her a happy anniversary!
Friday, June 10, 2005
Crackpots today... brain cells tomorrow?
We all know that Fafblog! is one of the funniest sites you can find on the internets, and in a somewhat darker vein Girls Are Pretty is extremely amusing. But if you're looking for sure-fire guaranteed entertainment, it's hard to beat Intelligent Design the Future, the new creationist website. It's always good for a laugh, especially when they start talking about physics.
A recent post finds contributor Paul Nelson rubbing his hands together in undisguised glee -- the physicists are talking about design!
Teapots today...cells tomorrow?I have to admit that I was a little worried upon reading this. George Ellis is a respected cosmologist, and co-author with Stephen Hawking of one of the best books on general relativity you can find, but he has been known to skate along the ragged edges of, shall we say, overly enthusiastic speculation. (Well, so have I.) And he is himself religious, indeed a Templeton Prize winner. (Well, so is Freeman Dyson -- nobody's perfect.)
Here is the quote from Ellis's essay:
Our environment is dominated by objects that embody the outcomes of intentional design (buildings, books, computers, teaspoons). Today's physics has nothing to say about the intentionality that has resulted in the existence of such objects, even though this intentionality is clearly causally effective.Well, okay. Ellis is talking about design, but in the context of things that we know perfectly well are designed -- football matches, teapots, or jumbo-jet aircraft. The fact that teapots are indeed designed is not worthy of media attention. Ellis's point in the essay is simply the old chestnut that reductionistic laws of physics are of little help if we want to understand many of the complex phenomena that we see in the macroscopic world -- even if every particle in your car is happily obeying the rules of the Standard Model, being a well-trained particle physicist won't help you when you muffler dies (as mine did yesterday). Read the essay for yourself; there's nothing in there about cells or higher purpose.
So how does Nelson take anything hopeful from Ellis? Let's see what he says.
Irreducible higher-level causation? From there it's a day's walk down an English country lane to current hypotheses of intelligent design. More resources here for the hard work of assembling a robust theory of design.Aha. Nelson turns Ellis's essay to his advantage via the venerable technique of "making shit up." The notion of "irreducible" complexity is much beloved by creationists; it's an advanced version of the standard argumentative fallacy of "if I can't see how it would happen, it must be impossible." Michael Behe uses the example of a mousetrap to illustrate a mechanism that would be useless if you removed any one of its component parts, and is therefore irreducibly complex. One problem with this notion is that nobody knows what it means, since no sensible definition of "irreducible" has ever been given. And of course, you can patiently explain to the creationists how mousetraps are not irreducibly complex, but they are strangely unmoved.
So it would be strange to find a real scientist talk about "irreducible higher-level causation." But then you look at Ellis's essay and -- he doesn't! The word "irreducible" doesn't appear anywhere in the article. Nelson kind of insinuated it into the text. And then it's "a day's walk down an English country lane to current hypotheses of intelligent design." The day's walk appears to take you from "teapots are clearly designed" to "cells are clearly designed." That's quite a long walk! I encourage Mr. Nelson and his colleagues to start walking, and report back to us when they reach their destination.
Thursday, June 09, 2005
Blogging on Odyssey
There was an excellent discussion about blogging on today's edition of Odyssey, the daily talk show hosted by Gretchen Helfrich on Chicago Public Radio. (Audio of the program is here.) The guests were Henry Farrell of Crooked Timber and Eugene Volokh of the eponymous Conspiracy. Host and guests were all smart enough to cut quickly through the equally bad caricatures of blogging-as-personal-diary and blogging-as-replacement-for-journalism that seem to be so prevalent out there in the complement of the blogosphere. They spoke eruditely about the uses of distributed communication networks, and elucidated the really useful purposes to which blogs can be put, including as sources of specialized knowledge and as alternative filters to an overwhelming stream of news items. (See also Eszter's comments.) Worth a listen.
What wasn't mentioned was the hidden expertise of the Odyssey crew: senior producer Josh Andrews recently started his own blog, The American Sector, and Gretchen was briefly a guest-blogger right here at Preposterous. No wonder they were able to uncover the deep truths of blogging so expeditiously.
A nice article about dark energy by Rich Monastersky in the Chronicle of Higher Education this week, unfortunately only available to subscribers. But I think it falls under fair-use doctrine for me to quote this one paragraph:
In the space of seven years, the dark-energy revolution has rewritten textbook entries on how the universe operates and what will ultimately happen to the cosmos. Yet dark energy is a nebulous concept, one that has thus far flummoxed some of the smartest researchers on the planet. "The fundamental physics of dark energy is a complete mystery to us right now," says Sean Carroll, an assistant professor of physics at the University of Chicago.Now, strictly speaking, what the paragraph says is that the smartest researchers on the planet are flummoxed by this problem, and also that I am flummoxed by this problem. So we cannot conclude, using the rigorous dictates of logic, that I am one of the smartest researchers on the planet. But if we look beyond the surface to the subtle subtextual implications, I think the message is clear.
Grief and truth
An interesting story from Killing the Buddha, linked yesterday at 3quarksdaily.
It's a good story, although not without the usual shortcomings of the Buddhist-parable genre. For one thing, the protagonist is rather literal-minded; how many homes did she really have to visit before figuring out that death was universal? Also, "kill-the-Buddha" exhortations notwithstanding, these stories inevitably end up portraying the Buddha as a smugly wise man surrounded by rather simple folk (much like physicists's stories about Feynman).
Still, I like the story and its moral. But then, a little twist:
That's exactly right, isn't it? In the midst of great grief, the overpowering sorrow that comes with an unexpected loss, you aren't in any mood for pious teachings about inevitability and acceptance -- you want a miraculous escape, a for-real deus ex machina. Nevertheless, the miracles aren't forthcoming. Wishing for them is both perfectly understandable, and ultimately fruitless.
Wednesday, June 08, 2005
Speaking of massive technological undertakings to explore high-energy particles, the Pierre Auger Observatory has announced that they've chosen the site of their northern-hemisphere location, which will be in Colorado. Auger uses a multi-technique approach to detect ultra-high-energy cosmic rays. There is a mystery about these UHECR's, namely that one experiment (AGASA) claims to observe them at higher energies (> 1020 electron volts) than should be possible. That's because the distribution in the sky looks the same in all directions, which seems to indicate that they are coming from far outside our galaxy (since galactic events should be concentrated in the plane of the Milky Way). But the universe is somewhat opaque to very high-energy cosmic rays; they tend to bump into the low-energy photons of the Cosmic Microwave Background and lose energy themselves. This should put an upper limit on the energy, known as the Greisen-Zatsepin-Kuzmin cutoff. If AGASA is right that they have detected events above the GZK limit (and maybe they're simply mistaken), then something funny is going on, either in the origin of cosmic rays or in the way they interact with ordinary photons.
The southern site for Auger is well underway in Argentina (as shown in the picture). They are presently collecting data, but with the first science results yet to come. Perhaps the northern counterpart will also have cows.
I've been meaning to write a little about my tour of the experiments when I visited CERN a few weeks ago. Sadly (or perhaps happily) I realize now that everything I was hoping to say was already said, at a level of precision I wasn't intending to reach, by Jacques in a report of his own visit to CERN. I'll say it anyway, but read his post for more details.
CERN, nestled in the Alps on the Swiss/French border by Geneva, is going all-out to complete the Large Hadron Collider by the target date of 2007. This is a giant ring that will accelerate protons in opposite directions, ultimately to smash into each other and (hopefully) create a bunch of new particles for us to explore. The energy of the collisions will be 14 TeV, where one TeV is about one thousand times the rest energy of a single proton; so there is more than enough energy available to see all sorts of fun things.
The LHC will have two large general-purpose experiments, ATLAS and CMS, and I had a chance to see each of them. (There will also be a nuclear-physics experiment, ALICE, and a B-physics experiment, LHC-b.) Both are truly amazing feats of engineering and physics. For one thing, they are big; each is of order 10,000 tons, and fits into a room the size of a large cathedral.
Here is a picture of ATLAS at the early stages of construction; to see its current state, check out the mandatory webcam.
CMS (which also has a webcam) is actually more impressive to see up close, as it is being put together as a series of slices, while ATLAS is being constructed more as concentric layers.
Interestingly, the reason why the experiments have to be so big is simply because of quantum mechanics. What we are really interested in is what is happening at extremely tiny distances. But the uncertainty principle tells us that we can't probe small distances without reaching very large momenta, or equivalently ultra-high energies. At the energies probed by the LHC, the particles produced in each collision come zooming out at tremendous speeds, and the extraordinary sizes of CMS and ATLAS are necessary to capture and analyze all of these many energetic particles. Each detector is a series of concentric layers that serve to measure the properties of different kinds of particles -- electrons and photons are easy, strongly-interacting particles (quarks and gluons) create elaborate jets, and muons require special treatment so that they don't just punch right through the detector. Other particles (W and Z bosons, tau leptons) decay rapidly and are diagnosed by what they decay into. Still others (neutrinos, not to mention various hypothetical new species) zip right out of the detector completely unseen, but their presence can be inferred from "missing energy," if the total energy of the reconstructed event is less than that of the initial collision.
As a theorist (and one who grew up in astronomy departments), one of the most fascinating concepts in high-energy experiments is that of a trigger. Each detector will witness approximately one billion collisions per second, which is a lot. You might imagine that you're faced with two problems: simply recording all the data from each event, and then sifting through them for the interesting bits. You're right, but it's much worse than you think. That's because each event isn't just a few bytes if data; it's of order one megabyte per event. There's simply no way you could record all of the data.
Instead, you try to figure out which events are "interesting," and record those -- perhaps 100 events per second. That's where the trigger comes in. While the data from each event are still streaming through the hardware, they are rapidly analyzed to see if they are worth keeping. This happens in levels; you do an ultra-rapid scan at the hardware level to see if anything potentially interesting is going on, and are able to cut down a billion events to about ten thousand. That's the level-1 trigger; the level-2 trigger is a sophisticated piece of software that looks at more precise characterizations of the events (much like an ER doctor making a preliminary rapid diagnosis, then homing in with more delicate tests) to get you down to the one hundred events that are actually recorded for later analysis. (This is all part of the great computing challenge that Mark discussed a while back.)
Why are some events more interesting than others? Quantum mechanics again. Particle physics doesn't predict what will happen at each event, only the probability that certain things will happen. The interesting bits (new physics, or events that help improve our understanding of established physics) will be swamped by well-understood processes, known affectionately as the "background." (A generation or two of physicists worked tirelessly to establish the gleaming edifice we know as the Standard Model, and now we think of it as simply "background.") As you might guess, a lot of hard thought (and spirited, collegial disagreement) goes into deciding which events to keep and which to toss away!
During my visit, the LHC folks seemed cautiously optimistic that they would really turn on the accelerator in 2007, and start taking useful physics data in 2008. All that will be necessary is the superhuman efforts of an army of physicists and engineers working twenty hours a day. But it will be worth it, as the LHC should revolutionize our understanding of the subatomic world. For the last 25 years or so, particle physics has been in an extremely unusual position -- the theory just worked so well that all the new experiments kept finding particles that had already been predicted. This is the opposite of the historically common state of affairs, in which experimenters keep coming up with unexpected new phenomena that the theorists have to scramble to understand (as we've seen in cosmology in the last decade). I fully expect the tables to turn once again when CMS and ATLAS start releasing new results. We have lots of ideas about what might be around the corner -- one or more Higgs bosons, supersymmetry, extra dimensions, various forms of strong dynamics -- but my suspicion is that what we see won't fit perfectly well into any pre-existing framework, at least not at first. That's when we theorists will really have to earn our salaries, and physics at the high-energy frontier will be as exciting as it ever was.
Monday, June 06, 2005
For those of you still looking for the perfect Father's Day or graduation gift, your prayers have been answered. Amazon.co.uk has wisely decided to offer my book in a special deal along with Lisa Randall's new book, Warped Passages (as noticed by Lubos).
To be honest, one book doesn't lead naturally into the other; Lisa's is a popular-level exposition of branes and extra dimensions, while mine is a graduate-level text in general relativity. But hey, you could do worse.
What I want to know is: who are John Neely and Richard Kibbe, and why does amazon.co.uk think they are co-authors of my book? I'm pretty sure I've never heard of these guys. Hope they're not cutting in on my substantial royalties.
Sunday, June 05, 2005
Rotting undead corpse of irony stalks again
I can't say it much better than Sisyphus Shrugged.
You know, frequently I think I've come to the point where the rotting undead corpse of irony will no longer stalk through my newsreading experience, shedding body parts and looking for sexually indelicate teenagers to eat, but somehow I always find that I'm wrong.
Friday, June 03, 2005
The Friday Random Ten idea needs some spicing up. Since nobody else runs with my ideas, let's follow up on the suggestion that we can use the iPod as a divination device. Simple enough -- just use the first ten songs that show up randomly exactly as you would use Tarot cards, and peek fearlessly into the future.
Here is the most common Tarot Spread, the Celtic Cross, as explained by Byzant Mystical. Each position plays a role in elucidating the larger story.
What really worries me is The Crown. If the best I can hope for is the allegorical equivalent of a minutes-long Ginger Baker drum solo, I'm in trouble.
Thursday, June 02, 2005
I understand that it's getting harder to tell -- so, just to be clear, what appears below really is a parody, courtesy of The Poor Man. Not that the real Corner is that much different.
GOLDBERG VS. WEINBERG, PART XXIII [Jonah Goldberg]
Wednesday, June 01, 2005
I like the theme of "lists made by conservatives that confirm that your worst fears weren't nearly bad enough." At Feministe, Lauren points to a post on a pro-life site that responds to her query about what "feminist" means. This list doesn't come from a panel of distinguished experts, so it's completely unfair to pretend that all conservatives think this way. But too many do.
Feminists:A short step from believing that contraception is okay to celebrating euthanasia, apparently. It's funny, when I look in the dictionary, I find that feminism is the "belief in the social, political, and economic equality of the sexes," which was somehow crowded off the list by "Hate Men." (Interesting choices of what words to capitalize, too.) There are people who really believe this stuff, and no amount of acquaintance with reality will sway them from their conviction.
But they are even-handed enough to admire Lauren's web design. It's exactly like the folks who are convinced that they're not sexist because they think that women are really pretty.