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Sunday, April 29, 2012

Higgs events in Erice 1990

In an earlier post I mentioned meeting Peter Higgs at Erice in 1990. An alert reader sent me the picture below, which was taken at the School of Subnuclear Physics in Erice that year. (Click for larger image.)

Seated in the first row are (I think) Dokshitzer, Ferrara, Weisskopf, Zichichi, Higgs (blue socks and sandals), a woman I don't recognize, Glashow, ?? , Ringwald. I am in a maroon shirt sort of behind Glashow.



Digging around in my photo album, I came up with the following scans from that week in Sicily.


On the beach in Trapani, with two French girls we met -- apparently their names were Sandine and Geraldine, but I had forgotten.




The Dirac operator acts on my Berkeley office mate. He's now a quant hedge fund manager.




The view from Erice.


Saturday, April 28, 2012

Information loss and energy nonconservation

Bill Unruh's KITP seminar on information loss and energy non-conservation stimulates a vigorous discussion of one of the key aspects of the black hole information problem.

The question is whether pure states can evolve into mixed states (decohere) without energy loss. The answer is of course yes, but many (perhaps most) black hole researchers are under the impression that a famous paper by Banks, Peskin and Susskind showed that information loss due to black hole evaporation must lead to observable (even catastrophic) energy non-conservation. (Theorists who accept the BPS argument all believe that the information is somehow encoded in the outgoing Hawking radiation, which may indeed be true, but it doesn't follow from BPS!) Unruh and Wald refuted this claim (to my satisfaction) years ago, but the subject is still controversial. The video at the link is entertaining even if you're not an expert on this topic. Bill's counterexamples are quite elementary.

Unfortunately, I missed this talk as I was giving a colloquium at UC Irvine the same day. At lunch the day before I urged Bill to "lay down the law" ;-)

Some related posts:

Spacetime topology change and black hole information

Black holes and decoherence

Crete talk: black hole information and decoherence

Thursday, April 26, 2012

L'oeuvre des enfants

The iphone is our main method of preserving the flood of creative works generated by the kids :-)

The boy is starting to learn algebra at age 6. I wish I had had someone around to teach it to me. My dad the professor spent very little time on that sort of thing. I grew up like the Draper kids in Mad Men.

Wednesday, April 25, 2012

UC Irvine colloquum

I should have put this up earlier in case anyone in the LA area wanted to attend. But I was too busy at KITP and forgot. UCI Physics Colloquium (slides).
Genetics of Intelligence and Other Quantitative Traits

Date: Thu, 04/26/2012 Time: 3:30 pm Location: RH 101

How do genes affect cognitive ability or other quantitative traits such as height? I begin with a brief review of psychometric measurements of intelligence, introducing the idea of a "general factor" or IQ score. The main results concern the stability, validity (predictive power), and heritability of adult IQ. Next, I discuss ongoing Genome Wide Association Studies which investigate the genetic basis of intelligence. Due mainly to the rapidly decreasing cost of sequencing, it is likely that within the next 5-10 years we will identify genes which account for a significant fraction of total IQ variation.

Afghanistan is lost

Listen to this interview.

[In contrast to the Russians ...] "We thought because we had good intentions, and if we treated people nicely, we could succeed. After 10-11 years and so many civilian casualties, most accidental -- there's only so many times you can say 'sorry we killed your family, but we're here to help you'. We've passed that point a long time ago ..."
Journalist and documentary-maker Ben Anderson discusses the war in Afghanistan, and his experience reporting on front lines in Helmand province. His book No Worse Enemy: The Inside Story of the Chaotic Struggle for Afghanistan is based on five years of unrivalled access to the US Marines and UK Forces, often for months at a time and amidst the worst violence the conflict has seen. It details the daily struggles facing U.S. troops in Afghanistan, and raises urgent questions about our strategies in there.

Tuesday, April 24, 2012

"Compounding returns of intelligence"

This is from Stanford's CS183 course on startups. The lecturers include Peter Thiel, Max Levchin and Stephen Cohen of Palantir.

Stephen Cohen: We tend to massively underestimate the compounding returns of intelligence. As humans, we need to solve big problems. If you graduate Stanford at 22 and Google recruits you, you’ll work a 9-to-5. It’s probably more like an 11-to-3 in terms of hard work. They’ll pay well. It’s relaxing. But what they are actually doing is paying you to accept a much lower intellectual growth rate. When you recognize that intelligence is compounding, the cost of that missing long-term compounding is enormous. They’re not giving you the best opportunity of your life. Then a scary thing can happen: You might realize one day that you’ve lost your competitive edge. You won’t be the best anymore. You won’t be able to fall in love with new stuff. Things are cushy where you are. You get complacent and stall. So, run your prospective engineering hires through that narrative. Then show them the alternative: working at your startup.
This is a good argument, although for some personality types the security and comfort level at Google might lead to more learning than at a stressful startup. Maximizing intellectual growth is one of the main reasons I chose theoretical physics over finance or (exclusively working on) startups.

Sunday, April 22, 2012

How the Higgs boson became the Higgs boson

IIRC, I met Peter Higgs in Erice in 1990. He was quite a nice fellow, but the story below by Steve Weinberg illustrates how capricious is the allocation of credit in science.
NYBooks: (Footnote 1) In his recent book, The Infinity Puzzle (Basic Books, 2011), Frank Close points out that a mistake of mine was in part responsible for the term “Higgs boson.” In my 1967 paper on the unification of weak and electromagnetic forces, I cited 1964 work by Peter Higgs and two other sets of theorists. This was because they had all explored the mathematics of symmetry-breaking in general theories with force-carrying particles, though they did not apply it to weak and electromagnetic forces. As known since 1961, a typical consequence of theories of symmetry-breaking is the appearance of new particles, as a sort of debris. A specific particle of this general class was predicted in my 1967 paper; this is the Higgs boson now being sought at the LHC. [ Higgs boson != Goldstone boson ? I suppose "general class" means any new particle associated with symmetry breaking ... ]

As to my responsibility for the name “Higgs boson,” because of a mistake in reading the dates on these three earlier papers, I thought that the earliest was the one by Higgs, so in my 1967 paper I cited Higgs first, and have done so since then. Other physicists apparently have followed my lead. But as Close points out, the earliest paper of the three I cited was actually the one by Robert Brout and François Englert. In extenuation of my mistake, I should note that Higgs and Brout and Englert did their work independently and at about the same time, as also did the third group (Gerald Guralnik, C.R. Hagen, and Tom Kibble). But the name “Higgs boson” seems to have stuck.

Saturday, April 21, 2012

California dreamin'

Joel Kotkin, writing in the WSJ, says California is headed in the same direction as Greece.

WSJ: ... Mr. Kotkin, one of the nation's premier demographers, left his native New York City in 1971 to enroll at the University of California, Berkeley. The state was a far-out paradise for hipsters who had grown up listening to the Mamas & the Papas' iconic "California Dreamin'" and the Beach Boys' "California Girls." But it also attracted young, ambitious people "who had a lot of dreams, wanted to build big companies." Think Intel, Apple and Hewlett-Packard.

Now, however, the Golden State's fastest-growing entity is government and its biggest product is red tape. The first thing that comes to many American minds when you mention California isn't Hollywood or tanned girls on a beach, but Greece. Many progressives in California take that as a compliment since Greeks are ostensibly happier. But as Mr. Kotkin notes, Californians are increasingly pursuing happiness elsewhere.

Nearly four million more people have left the Golden State in the last two decades than have come from other states. This is a sharp reversal from the 1980s, when 100,000 more Americans were settling in California each year than were leaving. According to Mr. Kotkin, most of those leaving are between the ages of 5 and 14 or 34 to 45. In other words, young families.

The scruffy-looking urban studies professor at Chapman University in Orange, Calif., has been studying and writing on demographic and geographic trends for 30 years. Part of California's dysfunction, he says, stems from state and local government restrictions on development. These policies have artificially limited housing supply and put a premium on real estate in coastal regions.

"Basically, if you don't own a piece of Facebook or Google and you haven't robbed a bank and don't have rich parents, then your chances of being able to buy a house or raise a family in the Bay Area or in most of coastal California is pretty weak," says Mr. Kotkin.

I dunno ... still looks pretty good here to me :-)


Thursday, April 19, 2012

Science and Engineering PhDs per hundred graduates

Interesting NSF data showing which undergraduate institutions' students are most likely to go on to earn science and engineering PhDs. (Click for larger graphic.)



Which institution produces the largest number US PhDs in absolute terms? See here.

Science 11 July 2008: A new study has found that the most likely undergraduate alma mater for those who earned a Ph.D. in 2006 from a U.S. university was … Tsinghua University. Peking University, its neighbor in the Chinese capital, ranks second. Between 2004 and 2006, those two schools overtook the University of California, Berkeley, as the most fertile training ground for U.S. Ph.D.s (see graph). South Korea's Seoul National University occupies fourth place behind Berkeley, followed by Cornell University and the University of Michigan, Ann Arbor.

The normalized figure for Berkeley is about 6% -- six times lower than Caltech.

Tuesday, April 17, 2012

Brain volume genes

I received many emails about this Nature paper: Common variants at 12q14 and 12q24 are associated with hippocampal volume, which purports to find an IQ gene. I had seen the paper before it went public.

The gene they found satisfies the genome wide significance threshold for correlation to brain volume, but not for IQ. If you adopt a Bayesian point of view that the gene is already interesting because of the volume association, and *then* test it for IQ association, you get a significant result (p < 0.05, or whatever). But it still needs to be replicated on larger samples.

The whole topic of the statistics of GWAS needs in-depth discussion but I don't have time right now. The genome wide significance threshold of around 1E-8 which has been adopted by the community and by journals is not entirely justifiable, but at least it has a good track record: results of this significance tend to replicate. On the other hand, from a Bayesian perspective we are throwing away a lot of information to ensure that the list of "hits" is nearly 100% bona fide. A hedge fund manager might be happy with a larger list of hits with, say, a 20% error rate. Homework problem: what is the right balance to produce the best black box phenotype predictor?

Monsters in AdS

Slides I used for the workshop discussion yesterday: What Part of the Asymptotically AdS Gravitational Phase Space is Dual to a CFT?

In classical general relativity one can construct configurations with fixed ADM mass but arbitrarily large entropy. These objects collapse into black holes but have more entropy than the area of the resulting black hole. Their interpretation in quantum gravity and in the AdS/CFT duality is an open question.

This topic is also nicely discussed by Don Marolf here and here.

It was great to have Bill Unruh in the audience, whom I had never met in person before.

Sunday, April 15, 2012

Sony is toast

See my post Sell Sony, buy Samsung from 2005 for comparison. Where is Ken Kutagari these days? Younger people today probably can't remember a time when Sony was a technology leader.

In 2005 it was clear to me that Sony was in trouble and Samsung on the rise. I also knew OS X and the iPod were going to be very successful, but I had been conditioned by MSFT's success to think that mediocrity would continue to rule in PCs and other computer products. So I certainly didn't think Apple's market cap would reach its current value.

NYTimes: Sony ... is now in the fight of its life.

In fact, it is in a fight for its life — a development that exemplifies the stunning decline of Japan’s industrialized economy. Once upon a time, Japan Inc., not to mention Sony itself, seemed invulnerable. Today, Sony and many other Japanese manufacturers are pressed on all sides: by rising Asian rivals, a punishingly strong Japanese yen and, in Sony’s case, an astonishing lack of ideas.

... Sony’s market value is now one-ninth that of Samsung Electronics, and just one-thirtieth of Apple’s.

Even in Japan, where many consumers remain loyal to the brand, some people seem to be giving up on the company.

“It’s almost game over at Sony,” said Yoshiaki Sakito, a former Sony executive who has worked for Walt Disney, Bain & Company, Apple and a start-up focused on innovation training. “I don’t see how Sony’s going to bounce back now.”

... Japanese consumer electronics manufacturers “have lost their technology leadership in many areas,” Steve Durose, head of Asia Pacific telecommunications, media and technology ratings at Fitch Ratings, said in a recent industry commentary.

“Ten years ago, these companies were major technology innovators, the creators or leading developers of many electronic products and trendsetting devices such as televisions, digital cameras, portable music players and games consoles,” Mr. Durose said. “Today, however, the number of products remaining where they can boast undisputed global leadership has narrowed significantly, having being usurped or equaled by the likes of Apple and Samsung Electronics.”

... Sony’s woes hurt not just Sony, but also Japan. In the United States, new technologies are often developed by young companies not held back by their past. These upstarts eventually replace slow-to-adapt giants. But in Japan, no major electronics manufacturer has joined the industry’s top ranks for over a half-century. [Unbelievable! But isn't this also true for other sectors in most European countries?] And, though struggling, companies like Sony continue to lure some of the country’s top talent.

... Some analysts wonder if Mr. Hirai — who previously ran the money-losing games and TV businesses — is the right man to lead Sony. A protégé of Mr. Stringer, he appears to have been appointed as much for his ease in English as his management skills, analysts say.

“The bottom line is: if you want to be perceived as a creator of cool tech, you have to create cool tech. The challenge for Sony is that those examples have not been there, and they haven’t been there now for a number of years,” said Steve Beck, founder and managing partner at cg42, a management consulting firm that focuses on brand vulnerabilities at top tech companies. “The tarnish on their brand has definitely begun.”

Saturday, April 14, 2012

Rethinking Finance

Mark Thoma points me to an interesting conference: Rethinking Finance.

Burton Malkiel's paper defines EMH to mean (roughly) "it's hard to beat the market, but of course prices could be way off at any particular time" (yes, Virginia, there are bubbles). This is what I refer to as a weak version of EMH.

Arnold Kling highlights the following talks (click through for links):

Foote, Girardi, and Willen ask whether, given expectations for ever-rising house prices, the institutional and regulatory details make any difference. If people expect house prices to rise faster than the rate of interest, then that creates in their minds a profit opportunity. One way or the other, the market will develop the financial instruments that allow people to exploit that apparent opportunity. I do not think I can endorse this view, but it is interesting.

Thomas Philippon asks how the financial sector came to be as large and profitable as it did. He argues that it is not because finance became more efficient or added more value to the economy. [ "In the absence of evidence that increased trading led to either better prices or better risk sharing, we would have to conclude that the finance industry's share of GDP is about 2 percentage points higher than it needs to be and this would represent an annual misallocation of resources of about $280 billions for the U.S. alone." ]

Brad DeLong asks why economists could not predict and explain the economic downturn. He argues that financial panics, in which the market's assessment of the safety of financial assets changes sharply and suddenly, are rare events that are outside the realm of typical theoretical models and statistical analysis. I am left with further questions. Which is abnormal, the faith that people had in financial assets before the crisis, or the lack of faith that people had after the crisis? And does government intervention to try to supply safe assets constitute the solution or the problem?

The Instagram story

I was shocked at the $1B Instagram acquisition, but then again I'm not exactly up to speed on the latest in iPhone apps or social networking. This Times article gives some background. Although the article stresses founder Kevin Systrom's Stanford connections, it seems like the go to guy was really a Caltecher ;-)
NYTimes: Past midnight, in a dimly lighted warehouse jutting into the San Francisco Bay, Kevin Systrom and Mike Krieger introduced something they had been working on for weeks: a photo-sharing iPhone application called Instagram. What happened next was crazier than they could have imagined.

In a matter of hours, thousands downloaded it. The computer systems handling the photos kept crashing. Neither of them knew what to do.

“Who’s, like, the smartest person I know who I can call up?” Mr. Systrom remembered thinking. He scrolled through his phone and found his man: Adam D’Angelo, a former chief technology officer at Facebook. They had met at a party seven years earlier, over beers in red plastic cups, at the Sigma Nu fraternity at Stanford University. That night in October 2010, Mr. D’Angelo became Instagram’s lifeline.

... For Mr. Systrom, the connections forged at Stanford were crucial.

Mr. D’Angelo, a 2006 graduate of the California Institute of Technology, helped him find engineers, set up databases and flesh out features. Soon after Instagram came out of the box, he put his money into it.

Tuesday, April 10, 2012

Bits, Branes, Black Holes



Greetings from Santa Barbara! I'm here at KITP for three weeks of Bits, Branes, Black Holes.

Theoretical physics action video and slides. (Opening session of the workshop: an overview of the black hole information problem. Highly recommended if you have the right background.)

Thursday, April 05, 2012

Higgs bosons, information and black holes

Sorry for the lack of posts. I've been a bit busy with this Higgs data meeting. It's fun to have people from both CMS and ATLAS (the two detector collaborations at LHC) together in an informal setting :-)

Next week (and for two more weeks after that) I will be at KITP Santa Barbara at the Bits, Branes, Black Holes workshop.

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