Monthly Archives: December 2008

Notes on BRST IX: Clifford Algebras and Lie Algebras

Posted on December 29, 2008 by woit

Note: I’ve started putting together the material from these postings into a proper document, available here, which will be getting updated as time goes on. I’ll be making changes and additions to the text there, not on the blog postings. … Continue reading →

Posted in BRST | 4 Comments

Physics Murder Mystery

Posted on December 27, 2008 by woit

After the recent news that Lisa Randall is writing the libretto for an opera, there’s further evidence that particle theorists in Cambridge are moving in the direction of creative writing. Today’s Wall Street Journal has a feature article about various … Continue reading →

Posted in Uncategorized | 13 Comments

Notes on BRST VIII: Clifford Algebras

Posted on December 21, 2008 by woit

Clifford Algebras Clifford algebras are well-known to physicists, in the guise of matrix algebras generated by the [tex]\gamma[/tex] -matrices first used in the Dirac equation. They also have a more abstract formulation, which will be the topic of this posting. … Continue reading →

Posted in BRST | 6 Comments

This and That

Posted on December 17, 2008 by woit

This week’s Nature has a nice cover story on Lyn Evans, who has been leading the construction of the LHC. The story mentions one of the problems of his high-profile job: Evans has found himself the subject of more than … Continue reading →

Posted in Experimental HEP News, Uncategorized | 27 Comments

Notes on BRST VII: The Harish-Chandra Homomorphism

Posted on December 15, 2008 by woit

The Casimir element discussed in the last posting of this series is a distinguished quadratic element of the center [tex]Z(\mathfrak g)=U(\mathfrak g)^\mathfrak g[/tex] (note, here [tex]\mathfrak g[/tex] is a complex semi-simple Lie algebra), but there are others, all of which … Continue reading →

Posted in BRST | 2 Comments

Status of Superstring and M-theory

Posted on December 11, 2008 by woit

A write-up by John Schwarz of his Erice lectures from this past summer has now appeared on the arXiv, with the title Status of Superstring and M-theory. In his second lecture, Schwarz provides a good review of the various attempts … Continue reading →

Posted in Multiverse Mania, Uncategorized | 10 Comments

Educational Malpractice

Posted on December 9, 2008 by woit

According to the New York Times, Scarsdale High School has decided to get rid of their Advanced Placement classes, including AP Physics, replacing them with a new curriculum that cost “$40,000 to bring in 25 professors from Harvard, Yale, New … Continue reading →

Posted in Uncategorized | 55 Comments

Notes on BRST VI: Casimir Operators

Posted on December 3, 2008 by woit

For the case of [tex]G=SU(2)[/tex], it is well-known from the discussion of angular momentum in any quantum mechanics textbook that irreducible representations can be labeled either by j, the highest weight (here, highest eigenvalue of [tex]J_3[/tex] ), or by [tex]j(j+1)[/tex], … Continue reading →

Posted in BRST | 8 Comments

BRST News

Posted on December 2, 2008 by woit

I should finish writing the next installment of the Notes on BRST series soon, but thought I’d post here about two pieces of BRST-related news, concerning the “B” and the “T”. The “T” in BRST is I.V. Tyutin, whose Lebedev … Continue reading →

Posted in BRST | 4 Comments

From Quarks to Strings

Posted on December 2, 2008 by woit

There’s a new preprint on the arXiv from Polyakov, entitled From Quarks to Strings, in which he tells the story of his involvement with string theory over the years. He begins: In the sixties I was not much interested in … Continue reading →

Posted in Uncategorized | 3 Comments