Category Archives: string theory

Quark Soup Al Dente

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Here’s Rob Myers in action, giving Monday’s excellent departmental colloquium, entitled “Quark Soup Al Dente: Applied String Theory”:

robert c myers quark soup al dente

Here was his abstract:

In recent years, experiments at the Relativistic Heavy Ion Collider have discovered an exotic new state of matter known as the quark-gluon plasma. Simple theoretical considerations suggested that this plasma would behave like an ideal gas, however, the experiments show that it actually behaves very much like an ideal liquid. Thus the standard theoretical tools, such as perturbation theory and lattice gauge theory, are poorly suited to understand this new phase. However, recent progress in superstring theory has provided us with a theoretical laboratory for studying very similar systems of strongly interacting hot non-abelian plasmas. This surprising new perspective extracts the fluid properties of the plasma from physical processes in a black hole spacetime. At present, this approach seems to provide some of the best tools which theoretical physicists have to understand the heavy ion collisions at RHIC.

For a very good blog post on this issue, see Bee and Stefan’s post at Backreaction.

It was really excellent to see Rob and spend some time with him at dinner afterwards and at lunch the next day with my students. We got to chat over a nice Tapas-style meal and catch up a bit on what each other has been up to (both in and out of physics – Rob is one of my most long standing friends and collaborators in the field), and he even gave us a seminar on Tuesday before leaving.

Now, here’s a physics question for you: […] Click to continue reading this post →

Questions and Answers about Theories of Everything

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joke hollywood star of brian greene Sometimes the journalists and editors get it right. In fact, they get it right a lot of the time, but you hear more about the complaints (sometimes from me, sometimes elsewhere) about them getting it wrong, when it comes to things like science coverage especially. What am I talking about? I’m talking about the set of questions and answers that are in a new article on MSNBC that a number of people pointed out to me yesterday and today. It starts out as an article about Brian Greene’s science outreach efforts (books, and tv and movie appearances, including a new one), with some discussion of how this is regarded by his colleagues, the value it has had in raising public awareness of physics (and fundamental science in general, I would argue), and so forth. All that is interesting, but not nearly as interesting to me right now as the later parts of the article which is simply a question and answer session. (Picture above right is from a fun joke I carried out last year that you can read here – be sure to read the comments too.)

Alan Boyle, the science editor, asks Brian a series of very thoughtful questions, and Brian gives some very thoughtful answers. The topics include research in string theory (of course), hopes and possibilities for experimental and observational results (such as from the LHC and Planck) that can inform and ultimately test the ideas coming from string theory and open up new vistas in fundamental physics, research on issues such as the landscape and the idea of multiple universes, research on better developing our understanding of string theory (to the point where we can, it is hoped, extract firm predictions from it), and many other things. (I wrote an introduction to aspects of the landscape issue here, and talked a bit about a Tom Siegfried article on the discussion amongst researchers here.)

It is nice to see an honest, non-inflammatory and non-hyped conversation about the issues, and read Brian’s personal take on some of these matters. The bottom is, […] Click to continue reading this post →

More Scenes From the Storm in a Teacup, VII

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You can catch up on some of the earlier Scenes by looking at the posts listed at the end of this one. Through the course of doing those posts I’ve tried hard to summarize my views on the debate about the views of Smolin and Woit – especially hard to emphasize how the central point of their debate that is worth some actual discussion actually has nothing to do string theory at all. Basically, the whole business of singling out string theory as some sort of great evil is rather silly. If the debate is about anything (and it largely isn’t) it is about the process of doing scientific research (in any field), and the structure of academic careers in general. For the former matter, Smolin and Woit seem to have become frustrated with the standard channels through which detailed scientific debates are carried out and resolved, resorting to writing popular level books that put their rather distorted views on the issues into the public domain in a manner that serves only to muddle. On the latter, there is a constant claim that string theory and its proponents are somehow brainwashing and/or frogmarching young people into working on that area to the exclusion of all else. The authors seem oblivious to some simple facts to the contrary there: (1) that you simply can’t do that to genuinely smart, creative young people; (2) that even students who have string theorists as their Ph.D or postdoc advisors often work on non-string theory research topics (3) that they’re doing an excellent job of either driving young people away from working on some of their favourite alternatives – or from pursuing theoretical physics altogether – by failing to clearly explain their merits and by using the press to help turn this into a distorted spectacle.

I’ve summarized a lot of what I think in the latter part of this post.

There are two major problems with how live debates take place in the public sphere. One is that the average person listening to the debate cannot know whether much of what Smolin and Woit claim as facts are right or wrong (or anyone on the other side of the debate, for that matter). When someone disputes a […] Click to continue reading this post →

New Directions in Real Estate?

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keats real estate imageOn NPR’s finance programme Marketplace yesterday, there was a somewhat unusual piece. It seems that conceptual artist Jonathan Keats is making some money by selling the extra dimensional rights to various properties in San Francisco! (You can see him at the Modernism Gallery there1).

Since there’s no known way to build on or otherwise occupy this new extra dimensional property (let me explain a bit further in an enormous footnote2), the prices are awfully reasonable. Here’s a transcript of a transaction that I found on their website. Reporter Nathaneal Johnson is observing a sale to punters Oscar Villalon and Mary Ladd:
[…] Click to continue reading this post →

Not Improbable

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elaine chewOn Wednesday night, accompanied by Tameem, a student of mine, I wandered across campus to attend the “Mathematics in Music” event. I blogged about it earlier. I don’t really want to talk about the event itself in this post. It was a nice enough recital of three pieces. I don’t know why, but the promised “mathematics” was disappointingly virtually non-existent. I’m not exaggerating, I’m afraid.

Keep in mind that it may simply just be my misunderstanding of the intent of the event, but there’s simply next to nothing to report in the way of what was said about mathematical aspects of music. There were plenty of opportunities, but (almost) none were taken. I got out my notebook and pen, all excited at what the presenters might say at various points… and the mathematics never showed up. There were a few extremely elementary remarks about tonal ratios in chords, about scales, keys, and time, and that was it, more or less. This was a bit of a shame, since I suspect that Elaine Chew could have talked at length and with some authority on the matter (given the projects she’s involved in see e.g. here), but mathematics was almost completely missing in the event – despite the title. I imagine there were what seemed like good reasons for this. I was not party to decisions made behind the scenes, so cannot comment further.

More interestingly on that front was what took place in the minutes leading up to the delayed start of the event. First, although it was a free event, they pointed us to the box office where an attendant printed us two tickets from the computer so that we can show them to someone at the door who wasn’t really looking anyway. Fine. We got into the recital hall, but rather than sitting at the obvious available seats, I suggested that we move to the other side of the room where one can get a better view of the piano keyboard. I’m less than happy when I can’t see what a musician is doing, you see, so I always try to sit with the pianist’s view of the piano. So we did that, and found two seats. While we chatted and looked around us at the growing assembly, I spotted a friend and colleague of mine, the composer Veronika Krausas. She was in the company of someone who she introduced as Brian Head, who is a composer, performer (guitar) and music theorist (a “triple threat”, Veronika joked), also in USC’s Thornton school of music. They were looking for seats and there was one on either side of the two we were sitting in, and so they joined us and we chatted some more.

When the event start was about ten or fifteen minutes late -they were trying to get the reassuringly large crown all seated, they announced- Veronika idly looked at her ticket, pointed out that they were numbered, and wondered if we should have been […] Click to continue reading this post →

All Hands on Deck

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all hands on deck Well, it’s the middle of the Bleak Midwinter, and the first day of classes of the new semester. Mine start tomorrow. It is time to get myself back into the classroom-teaching frame of mind -although to be honest I don’t think the break was long enough for me to have got sufficiently far removed from it: 85% of the research tasks that I wanted to do during the break remain undone.

Anyway, I must sit and contemplate what I am going to talk about in the graduate course entitled “Selected Topics in Particle Physics”. It’s my lunch break, so I thought I’d chat to you for a bit.

Rumour has it that everyone is expecting some sort of string theory course, reasonably complementary to the one that my colleague Nick Warner taught here two years ago. I’ve no interest in just teaching the standard string theory topics – a good and motivated graduate student can just look them up in a book if motivated enough (if they can’t they’re in the wrong business) – and so I’d like to throw in some material that is not packaged together in the standard way, and give them an education that emphasizes powerful ideas and techniques that are relevant to more than just standard string theory research, but theoretical physics in general.

You see, this is one of the wonderful things about the topic that you don’t hear about much when people say things (and write books for a general audience) about how much it is supposedly taking over smart young minds and leading them astray: It is a fantastic framework for training good physicists for whatever new and useful ideas and physics will come along in the future, whether it is string theory or some other topic. The point is that string theory has developed in so many different ways, and […] Click to continue reading this post →

Masterclass

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You’ve possibly been following my efforts over here to discuss and explain the several weaknesses in Smolin’s and Woit’s arguments and positions, and why the current “string debate” is all an overblown (and media-fueled) fake controversy. (See for example the series of posts entitled “More Scenes from the Storm in a Teacup”, the last three especially, (links: I, II, III, IV, V, VI); use the search engine for other instances.)

I’ve no idea what the effect of these discussions has been. Woit recently said “my views haven’t changed at all”, and so has covered his ears and dug his heels in while Smolin has written some sort of response on his website. I don’t hold out much hope for them, but I do hope that readers of these discussions can see that there’s been a fair amount of wool pulled over their eyes, to say the least.

What to do? What more to say? Whatever more I say, I cannot say it all any better than Joe Polchinski, a true master from whom we’ve all learned so much physics. Read his review in a guest post over on Cosmic Variance!

-cvj
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Shocked Reaction

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For a refreshingly straightforward point of view from a young person in the field who just wants to get on with doing some good physics with what seems like a promising approach, read Jonathan Shock’s description of his recent attendance of meetings (including the one to which I earlier referred) on heavy ion collisions and related physics. (See also an interesting comment by Xin-Nian Wang on the comment thread of my earlier post.) Jonathan gives some useful links to presentations on some of the attempts to model some of the new physics using string theory models.

The title? Oh, yes, he gets beaten up a bit by those around him for working on strings. […] Click to continue reading this post →

Southern California Strings Seminar

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On Friday and Saturday of this week (December 1st and 2nd), the next Southern California Strings Seminar will be happening! It’s a regional meeting for people doing research in string theory and related topics, and as I’ve said before, I’d especially like to see more young people come out and take part. We make a special effort to ask the speakers to spend a little time at the beginning of their talk setting the scene (speaking about motivations, what has gone before, etc) so that the series can be of great value to people who are trying to learn what’s going on in a particular topic at research level (this can be students, postdocs, or faculty, in fact).

If you’re doing this kind of physics research anywhere in the Southern California region, and want to take part, please come. See the website for details, and try to let […] Click to continue reading this post →

Nuclear Guy Goes Nuclear

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star rhic goldFollowing on from her earlier post (with Stefan) on the research effort to understand Brookhaven’s RHIC physics with string theory, Bee reports some things she heard about a nuclear physics conference in Shanghai (Quark Matter ’06). Apparently Larry McLerran -who is at Brookhaven- did a 20 minute anti-string (and anti-Brian Greene) rant. You can see some slides etc, over there.

(Note for the non-expert:- RHIC means “Relativisitc Heavy Ion Collider”. Picture on right (click for larger): Tracks from collision of two beams of gold nuclei -the heavy ions- recorded by the STAR detector at the RHIC experiment. More here. In a sense, a new form of matter is formed in these conditions – the issue is how to understand its properties.)

This sort of thing is rather funny, so far (apparently Brian Greene was given a “Pinocchio award” in the talk?! ). Let’s hope it does not turn into something serious.

In moving forward: […] Click to continue reading this post →

More Scenes From the Storm in a Teacup, VI

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A quick update:

* There was a second installment of the discussion led by George Johnson about press coverage of string theory. He went back to look to see what exactly some of those early articles said… How much coverage was there to start with? When did it start? When did it begin get out of hand? Did it get out of hand? Is this all just part of a standard bubble that happens for any field that the press decides to cover, a sort of manufactured (my word not his) boom and bust cycle? All issues that were touched upon in the discussion. Note also that the discussion broadens out considerably -as it should, (finally!)- to talk about the broader issue of coverage of topics in physics and science in general. The positive and negative effects of press coverage on attracting the next generation of students was also discussed. The discussion (this aspect in particular) was especially interesting because of the remarks by a number of senior people in the audience who were able to talk about their experiences over the years having seen the cycles recruitment of students in their own departments. Worth a listen/look at the archive here.
* Lee Smolin has written a “Dear Friends” letter in response to some of the things that have been pointed out about his book, and about other points he’s made publicly in various discussions. He’s given over some time to write quite a bit, which in general is a good thing to have done. You can find it here.

I’ll leave it to you to form your own opinion about Smolin’s remarks (I’ve not had time to read it in detail yet), and start a discussion here. Maybe ask him some followup questions here, for example. To help with context and build a more complete picture, do read some of the earlier comments and discussions involving him -and questions put directly to him- on the threads that share the name of this post. (e.g., Here and here.) Put those alongside the discussion with Peter Woit and of the central thesis of Woit’s book too. They are inseparable.

My set of opinions on the issue is the same as it was before. Even though I’ve said it all so many times here, since blogs seem to have no memory, I will summarize a bit:

[…] Click to continue reading this post →

String Theory Goes A Little Bit Country?

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n these hard times for basic science research, scientists look elsewhere for supplementary financial support. It seems that the monolithic entity simply known as “String Theory” is trying to diversify its funding sources even more creatively than before! Some recently spotted* evidence in the Nashua Telegraph in New Hampshire:: […] Click to continue reading this post →