John Baez has a new issue of This Week’s Finds. He has a lot of interesting things to say about Euler characteristics and how you measure sizes in a category. Among many things I learned from Graeme Segal when he was here last semester was the idea of thinking of the Faddeev-Popov prescription in the path integral approach to gauge theory as reflecting the fact that one should think of gauge fields as a category. The category is the category whose objects are bundles with connection, and gauge transformations are the automorphisms of these objects. The general principle that when you count objects in a category you need to divide by the number of automorphisms provides a sort of motivation of the Faddeev-Popov calculation.
The US FY 2007 budget situation for math and science, which was looking very bad just recently, has taken a huge turn for the better as the House has voted to increase funding for the DOE Office of Science and the NSF. More information about this here, here, here, and here. Looks like Fermilab and RHIC will emerge from the budget process unscathed. Soon the president’s FY 2008 budget proposal will be unveiled, and we’ll see what the new Democratic majority will do about science funding.
This week’s press release announcing a “test of string theory” is from the University of Wisconsin (also here, here, and undoubtedly elsewhere). It’s no competition at all for last week’s spectacular press releases about “string theory tests”, but like the many other examples of the genre it is designed to make claims about string theory highly likely to mislead unsuspecting readers. I made some comments about this here. It’s not really that hard to come up with these “tests of string theory”, since “string theory” now has been invoked to justify studying a huge variety of different kinds of models, and is compatible with just about anything. All you have to do is find one, no matter how complicated, obscure and lacking any evidence or motivation, where you can choose the parameters so as to create effects not visible to current experiments, but perhaps visible to potential experiments, even ones many decades down the road. Without too much trouble you should be able to get a paper about this published, and at that time your university press office will surely be happy to put out a press release for you announcing that “Researcher(s) at University X have discovered a way to test string theory.” This has been going on for years, and people seem to never tire of it.
Sean Carroll seems to find it amusing that many articles on the arXiv can now be thought of as a new form of performance art. John Horgan, who got a lot of grief years ago for accusing physicists of engaging in “ironic science”, should really enjoy this.
Update: The Distler et. al. media juggernaut rolls on, informing the world that : The LHC, due to be finished by and running by the end of the year, may rule out the string theory, as well as the work by Distler and his colleagues offers something profound – a way to actually test string theory, and that if Distler’s bounds are satisfied, it would provide a weak support for string theory. The last article quotes Distler to the effect that string theory is just an “effective theory”, which I’m sure will clarify this for the public.
Update: The Shiu et. al. “test of string theory” press release has also led to lots of misleading stories. For an example check out Physicists devise test for string theory, where you’ll learn that “the University of Wisconsin theorists predict that upcoming experiments on the European Space Agency’s Planck satellite will have the sensitivity needed to prove the case for string theory.” Somehow I suspect string theorists will not give up on string theory if the Planck data doesn’t work out, and there won’t be any press releases…