Category Archives: string theory

Chiropteral Mirror Symmetry?

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Spurred by the previous post showing M-theory’s possible relation to matters Chiropteral , Joe Polchinski (who I think, in 1995 or 1996, first drew the diagram that I messed with in that post) emailed me* to say that there is a quite striking appearance of batman-ology in the string theory literature. It’s from one of the classic Mirror Symmetry papers of 1990 by Candelas, De La Ossa, Green, and Parkes, “An Exactly soluble superconformal theory from a mirror pair of Calabi-Yau manifolds.” (you can find it via here). Here it is:

batman ish mirror symmetry diagram

What is this? It has to do with spaces in string theory called “Calabi-Yau manifolds”, which are important (in some approaches) as starting points for constructing models […] Click to continue reading this post →

Fourth Thoughts

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Have a Fantastic Fourth of July, to everyone who is celebrating it!

fantastic four promotional skywriting over LA on the July 2005

It’s been several days since my last confession. Sorry about the silence. I’m honestly not sure exactly what I’ve been doing, since it has been a mostly fragmented set of things, coupled with a generally down mood of introspection over matters personal. Hmm… So nothing new there.

Physics-wise I’m a bit stuck. Not on a particular project this time, but stuck on […] Click to continue reading this post →

News From The Front, III

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[Note: Originally posted on CV on 4th November 2005. 25 comments on it here. Feel free to add new ones here.] ___________________________________________________________________________________ [Warning! This is an unusually technical post.] Ok, so last time, I told you a bit about the motivations for what I’ve been up to. Now I want … Click to continue reading this post →

News From The Front, II

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[Note: Originally posted on CV on 31st October 2005. 31 comments on it here. Feel free to add new ones here.] ___________________________________________________________________________________ Well, I suddenly have 45 extra minutes on my hands as I was supposed to be at a very interesting two hour lunch meeting which I’ve now missed. … Click to continue reading this post →

News From The Front, I

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[Note: Originally posted on CV on 3rd October 2005. 65 comments on it here. Feel free to add new ones here.] ___________________________________________________________________________________ Below is a snapshot of a computation I was working on earlier this Summer. Will explain later. Spoke about it at the Southern California Strings Seminar. I’m curious … Click to continue reading this post →

Old News

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The next three posts are repeats of posts I did on CV in 2005. They were the first three in the series entitled “News From The Front”, and their subject matter partly lay the groundwork for a post on some new results that I hope to write soon. Enjoy! -cvj

Infiltration

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Ok, so which one of you is responsible for this? (Since I started writing the post, I’ve since learned the answer – see below.)

futuramas professor farnsworth with wittens dog

I was watching the 1999 Mars University episode of Futurama some nights back. It’s the one where Professor Farnsworth teaches (among the many excellent lines: “I can’t teach, I’m a professor…”) a course entitled “The Mathematics of Quantum Neutrino […] Click to continue reading this post →

It Might as Well be String

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title banner from a Goodies spoof documentary about string

A reader asked for more string. You can see my reply here. Not being one to deny the punters entirely, title banner from a Goodies spoof documentary about stringI’ll pass on some clips from a 70s British TV comedy show, about string. It was a popular show called “The Goodies”. Some of you might remember them. Well, they did an entire episode with the title “It might as well be string”, and although the clips (below) are out of context and even with not knowing the characters and so forth (I don’t) there are some amusing bits here and there, if you turn it around to poke harmless fun at those of us who work on string theory decades later – It’s all about a PR/Advertising campaign for string!

There’s the string song, the “documentary” about string (best to gloss over the oh-so-funny “smelly Arab” remarks and accompanying laughter), the excellent samples from the […] Click to continue reading this post →

Some Unusual Recipes

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Quark Gluon Plasma RecipesWell, I’ve been quiet here because I got rather swamped with lots of things over the last few days. The biggest thing was yesterday. I gave a colloquium at Caltech entitled “Cooking with Quarks and Gluons: Recipes from the String Theory Kitchen”. The abstract is given below. It is mostly based on what I wrote about last Summer.

With all the other things I had to do (including writing and giving two fun two hour lectures on cosmology in my undergraduate GR class) I still decided that it was time to totally rethink how I tell this exciting physics story, and how I present it. This meant designing and building many new slides. Each slide can take a long time to prepare, so this took two solid days of hiding away while designing and building them, only breaking for the other stuff.

Well, it was fun in the end, and today I am exhausted. I decided that you should not miss out entirely on the treats, so I made a little movie of the first parts of the talk to […] Click to continue reading this post →

Southern California Strings Seminar

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Takuya Okuda talking at the SCSS at UCLA, Dec. 2007

Takuya Okuda talking about Wilson Loops at the most recent SCSS, UCLA, Dec. 2007. Click to enlarge.

The next regional string meeting is a two-day one at Caltech, this Friday and Saturday, organized by Joseph Marsano. It’s going to be full of interesting talks and conversations, as usual. Please encourage your graduate students to come, especially, since special effort is made to make sure that each talk begins with a pedagogical portion to help non-experts in that subfield navigate and see the motivation.

The speakers are: […] Click to continue reading this post →

Bigger than the FCC

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We’ve been studying rotating black holes in my class this week, which has been fun. We get to apply the techniques we’ve been honing in the context of the Schwarzschild solution (link to recent posts below) to a bit more complicated solution, the Kerr solution, which includes rotation. Some equations follow, although you needn’t be put off by them. Most of this will make sense without really understanding them much. Just so you can see the shape of the things we scribble, I’ll show you the equation that captures this curved spacetime geometry, with no real explanation (sorry):

kerr solution

Here [tex]\Delta\equiv r^2-2Mr+a^2[/tex] and [tex]\rho^2\equiv r^2+a^2\cos^2\theta\ .[/tex] The parameter [tex]a[/tex] is the ratio of the solution’s spin or angular momentum [tex]J[/tex] to its total mass [tex]M[/tex], measured in appropriate units. It’s a very important solution to get to grips with, since it’s not just fantasy physics, but highly relevant for astrophysics since black holes that are “out there” are unlikely to be non-rotating, and in fact, one can expect them to be rotating at quite a clip in many cases. A good many black holes – including some of the […] Click to continue reading this post →

Beyond Einstein: Fixing Singularities in Spacetime

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Not long ago David Morrison (UCSB) came to the mathematics department here at USC to give a colloquium.

David Morrison Colloquium at USC

This was a treat for me for many reasons. Here are three:

  1. It’s always good to see Dave. He’s one of the people I’ve known in the field was since my very first postdoc when I was learning to survive in the big bad world on my own after graduate school. I mostly could not understand a word he or anyone there else said in those days (IAS Princeton, right in the belly of the

[…] Click to continue reading this post →

Nick Halmagyi: Why I do Science

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Nick HalmagyiI’m pleased to introduce a guest blogger today. It’s Nick Halmagyi, who you might have seen comment here from time to time. Nick is a postdoctoral researcher in Theoretical Physics, currently at the Enrico Fermi Institute in Chicago. Before that, he was a graduate student in our High Energy Physics group at USC, which is where I met him. Nick wrote his reflections below for Seed, and he reproduces a version of it (with permission – see details below*) here. I hope you enjoy it.

-cvj

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Theoretical physics is a tough subject. Just one example of how hard things can get is when you ramp up the energy density of a system, the physics used to describe the system itself starts to change. At first it may be a small tweak in the parameters that appear in the equations (the electric charge for example), but then there can be large, abrupt transitions.

The biggest system we study is the universe, and immediately after the big bang all of its energy occupied a tiny region of space. Back then, the energy density was enormous, and as the universe grew over time it underwent several transitions before it became what we now observe.

I’m a theoretical physicist, in part, because I relish the challenge of studying the entire […] Click to continue reading this post →

Southern California Strings Seminar

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michael gutperle talking at the first SCSS at USC, Sept. 2005The next regional string meeting is a one-day one at UCLA, organized by Michael Gutperle and Per Kraus. It’s going to be full of interesting talks and conversations, as usual. Please encourage your graduate students to come, especially, since special effort is made to make sure that each talk begins with a pedagogical portion to help non-experts in that subfield navigate and see the motivation. (Photo: Michael Gutperle talking at the first SCSS at USC, Sept. 2005; click for larger view.)

The speakers are: […] Click to continue reading this post →