Category Archives: string theory

News From the Front, IV

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So imagine the following:

You’re walking along the street, minding your own business, and somebody walks up to you and tries to sell you a string theory. So you stop and examine the goods, since you’re in the market for string theories, on the lookout for any that might be novel, useful, bright, or shiny, etc. You never know when one or other property might come in useful.

Question: How do you know that it is a string theory? Let me be sure to point out that it comes with a lot of the defining path integral done for you. In other words, you don’t have to do the integral over string world sheet metrics and world sheet fields. This was done in the factory for you. What you have access to are parameters such as the coefficients of the operators in the theory, and you can also adjust the value of the string coupling.

So a lot of the stuff you would recognize as a string theory in your typical string theorist’s notebook have been cleaned up. They’ve been integrated over. The observable physics actually never cared about them (the technical details of summing over metrics – slicing up the moduli space of inequivalent metrics properly at each genus, etc etc…. all done), assuming you’ve done the integrals properly. The factory did it all for you.

So what criteria do you use to decide that it is a string theory at all? Actually, this is not an idle question. Think about the issue in the context of trying to understand some […] Click to continue reading this post →

More Scenes From the Storm in a Teacup, IV

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Finally we get to some real substance in the program! (See earlier notes, and thoughts.) Jeff actually mentions all the effort going on string theory and experiments at Brookhaven, and asks that question I keep asking everyone… “why oh why is this never mentioned by the press in these discussions?” I’ve asked this of Peter Woit on his blog a lot too, for example, and have never got much of an answer. Peter and Lee want the world to believe -by reading their books- that the entire field of string theory is just people sitting around discussing the Anthropic Principle and lots of different universes, and blah blah blah… It serves the purpose of the books in question to completely distort the view of what is actually going on in the field. They claim that there is no experimental support (true) or hope for experimental support (how can they know that?) for string theory… but they ignore the fact –they intentionally don’t tell you, dear reader– about the interesting work going on by a huge percentage of the field to use string theory to study the structure of nuclear matter. It is still in its early stages, and may not work, but it is rather interesting. As Jeff put it, about the new form of matter that is constructed in these experiments, string theory is “the only approach that I know of” that currently seems to be able to explain the observed properties….

Lee, about the omission of this huge effort in string theory research from his book: […] Click to continue reading this post →

More Scenes From the Storm in a Teacup, III

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Poor Jeff!

I’m listening to the program now, and 40 minutes into it, there’s been long sections of completely pointless waffle by Lee and the presenter (the latter keeps reading long and largely peripherally relevant quotes from philosophers), broken up by breaks to shout the name of the station at you…. then long musical ditties… then back to more waffle…. and then the few times Jeff gets to come in, he is interrupted again by the presenter with more irrelevant stuff about philosophy. Jeff managed to say at one point “I’d rather talk about what can be measured, what we can calculate…”, but this seems to have been ignored. He is given a little time to start to explain what strings is about….

A bit later…. Lee is just going on and on and on and on about…. uh…. crap and utter irrelevance. The battle between Liebniz and Newton. Relational vs absolute. Sigh. I just don’t get it. Why is this happening? Another music/station reminder break…

A bit later…. Jeff finally manages to get a bit of a word in. He has to jump in at one point when […] Click to continue reading this post →

More Scenes From the Storm in a Teacup, II

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I just heard* that at 9:00pm Chicago time, there will be a discussion between Lee Smolin and Jeff Harvey, presumably about string theory, and you can listen to it live on radio station WGN, here.

Thinks:

* I wonder if it will be as utterly content-free and pointless as the one that took place between Lee Smolin and Brian Greene on Science Friday some weeks back? That one was so annoying in places that I never finished the blog post I was writing about it. It was mostly of the following structure (I paraphrase):

Lee says wise and learned things like “there should be a diversity of effort in approaching problems in fundamental physics”.

The host, Ira Flatow, turns to Brian (on telephone link) and says “what do you think of that, Brian Greene?”

Brian says, “Yes, I agree. I have several students working on things outside of string theory.”

…thus blowing a bit of a hole in the claim that string theory is this cult/monolith that somehow blinds us all to other great ideas.

* I wonder if Lee will bring out what I consider to be one of the most ridiculous things I’ve heard said by him (or anyone else) in this largely-media-and-self-interest-driven “debate” spawned by his and Peter Woit’s books. Paraphrasing: A good idea has about ten years to come to fruition, and then if it does not, it is wrong and should be thrown out.

Lee does say some wise (if mostly obvious) things about the field from time to time – some of which are well worth remembering, and sometimes it comes from his knowledge of how things have worked in physics in the past. Yes, we should remember our history….. but this statement seems to spectacularly ignore history and ranks right at the far opposite end of the scale of “wise things”. Ten years?! And even if you could put a time to it… is this what we are telling the general public about the way we do science? By putting time limits on ideas?

Overall, this storm in a teacup -which will continue, because the media only wants to hear an “underdog” story right now, whether or not it reflects what is going on in the research itself- is simply poisoning the well for everyone, whether they do string theory or not. See here.

Lee and Peter, I agree that string theory is often over-hyped, and has been for some years now (let us not forget, by the way, that it is the same media who helped out with that hype who is helping to drive the new anti-string hype -classic bait and switch-) and that it has made some physicists working in the field a bit annoyed. But here is how not to fight against that: Counter-hype.

Remember:

* An eye for an eye and a tooth for a tooth leaves everyone blind and sucking up their favourite meals through a straw.
*

Fighting fire with fire leads to everything burning.

-cvj

(* Thanks, Nick!)
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More Scenes From the Storm in a Teacup, I

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Aaron Bergman has written an extensive review of Peter Woit’s attack-book on string theory. I’ll let you read the thoughtfully written 11-page pdf document linked there. I think that Aaron deserves some sort of medal or other award for making the effort. Peter responded here. Note from the title that … Click to continue reading this post →