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Agent of change
August 25, 2008
Our Pathetic News Media
The USA/Today reports
While Obama leads McCain 48%-42% among women in a USA TODAY/Gallup Poll released Sunday, Biden’s family life and his legislative record on women’s issues could help win disappointed fans of Hillary Rodham Clinton and enlarge that gender gap.
First of all, 48%-42% was McCain’s lead over Obama among men. In that poll, Obama lead McCain among women by a whopping 49% – 39%. To achieve that large a lead among women overall, his lead among women Democrats must be overwhelming.
And yet, our benighted news media are so insistent in their narrative about “disappointed fans of Hillary Rodham Clinton” that they need to resort to misreading their own polls to propagate the story.
August 20, 2008
Instiki + IE7
Somehow (doubtless, because I try to stay as far away from Windows as possible), it eluded my attention that there was a serious bug when viewing Instiki pages in IE7+MathPlayer. The problem doesn’t occur with IE8β+Mathplayer or, as best I can recall, with IE6+MathPlayer. But, with IE7, instead of displaying the page, it showed you the XML source tree instead.
The problem turns out to be involve the HTTP Content-Type header. If you send IE7+MathPlayer the header
Content-Type: application/xhtml+xml; charset=utf-8
you trigger the bug. If, instead, you omit the charset parameter,
Content-Type: application/xhtml+xml
all is well.
Getting Rails to omit the charset parameter turns out to be surprisingly difficult. If you want to see how to do it, search for “MathPlayer” in this file.
Technical details aside, the latest version of Instiki finally works with IE7+MathPlayer.
Thanks to Timm Wrase for reporting the problem (best of luck in Munich, Timm!), Neil Soiffer for confirming its origin, and Sam Ruby for working to ensure that Rails 2.2 will solve the problem in a less convoluted way.
August 2, 2008
Noncommutative
From time to time, I’ve been asked what I think of the Connes-Chamseddine-et al “Noncommutative Standard Model”. I haven’t had anything terribly profound to say, but recently I got involved in a conversation with Urs Schreiber about it. So, perhaps it might be useful to summarize what was said.
July 31, 2008
Best Fit
Via Tommaso Dorigo, Pete Renton’s talk at ICHEP08, a report on Global Electroweak Fits and the Higgs Boson Mass. Incorporating the latest Tevatron data,
- GeV.
- GeV.
- GeV at the confidence level.
- GeV (highly sensitive to and ).
July 30, 2008
Wall Crossing
Many of the magical result in string theory and supersymmetric gauge theories have been motivated by consideration of the spectrum of BPS states in these theories. For 16 supercharges (), this spectrum varies continuously as one moves through the moduli space. This fact is at the heart of the S-duality conjectures. For 8 supercharges ( supersymmetry), the spectrum of BPS states jumps discontinuously, as one crosses “walls of marginal stability”. As a consequence, there is usually no manifest S-duality for theories.
Describing exactly how the spectrum of BPS states jumps is, however, a complicated business. and a lot of effort has gone into deriving “wall crossing formulæ.” Recently considerable progress was, apparently (I say “apparently” because the paper has not yet appeared on the arXivs), made by Kontsevich and Soibelman, who proposed a wall-crossing formula for Seiberg-Witten Theory. Gaiotto, Moore and Neitzke provide a beautiful physical explanation for Kontsevich and Soibelman’s result.