Reluctant Retirement

Well, the time came last week. After several years of service, and a valiant attempt to stay in service even with illness and infirmity, there was nothing to do but go for retirement, and let a replacement take over.

Wait – No, not me! I’m talking about my trusty Sony Ericsson T616, of course. A bit of gadget babble follows. You’ve been warned: It is a wonderful phone, and of course, being the conservative (read: boring old) person that I am, I pretty much wanted the same phone again. Of course, progress (as they ironically call it) meant that it can no longer be found in any store, so I tried to find whatever phone Sony Ericsson had made to replace it. (Side note: I’m waiting a few years for the iphone to get to a sensible price and go through an update or two before I go in that direction.) They’ve made some good-looking ones with excellent specs – proper grown-up looking phones with grown up capabilities. Not hip toys for the (post post) MTV generation, you understand. They’re fine (and often full of great features too, I know), but just not me.

retiring the T616 phoneDoes my phone company (AT&T) do them? Strangely, not any more, and hardly any others, as far as I could see. Meanwhile, you can get them in Europe all over the place (what with their being so far ahead on these things, as usual), which is really no use to me here. So this put me into a bit of a haze for a few days since I really don’t want to go the way of the cutesy flip phone – like one of those RAZR, KRZR, etc., models that everybody -and I mean everybody- seems to be getting. I’m not a huge fan of flip phones in general (I went through that phase a while ago) and furthermore a lot of Click to continue reading this post

The 9/11 Flip

Dijkgraaf Verlinde Verlinde 9 -11 flip figureOk, so here goes. A bit of physics linked to this all so significant date. There’s this term that people in string theory were using a lot in the middle to late 90’s, called the “9/11 flip”. I think maybe the Verlinde brothers, Erik and Hermann, possibly in conjunction with Robbert Dijkgraaf, made the term popular but I am not sure about that and I welcome a correction. [Update, since there is some confusion: I’m talking about the term here, not the technique itself, which is older.]

(On right (click for larger) is a snapshot of one of the figures from their influential 1997 “Matrix String Theory” paper. You can see the use the term there, and it is in the paper’s text too, and soon everyone was using it in seminars and other papers to follow.)

The flip became particularly useful when people were discovering the wonders of “M-theory”, which is the catch-all term for whatever is the parent theory of string theory, something we are still trying to formulate. There are a number of narrower uses of the term, however – some more justified than others. For a while, everyone was thinking about the five ten-dimensional supersymmetric string theories (“type IIA”, “type IIB”, “type I”, and two types of “heterotic” theory) which, prior to the middle of 1995 (actually as early as late 1994 or early 1995) all seemed like totally distinct theories, and in the post middle-1995 era (after Witten’s remarkable talk at strings 1995 here at USC: paper here) were recognized to be all part of the same theory. The universe (at least the continually expanding string theory one) changed radically overnight.

m-theory puzzle
(One of my preferred ways of presenting the puzzle that is M-theory, and how the ten dimensional string theories fit in the puzzle. This is a slide from one of my general talks on the subject.)

The 9/11 flip is really simple, although when a setting is complicated enough, it can Click to continue reading this post

That Sort of Time

Yes, it has been that sort of time. The last several days have been full of far too many things – several of which it would be fun to blog about – but none of which have left me any time for doing the actual blogging part. What sort of things? Well, everything from social gatherings like a couple of parties and salon-type events on the one hand, the usual work-type events on the other (like yesterday’s reception to welcome new USC College faculty – I find those especially important to show up to as a means of re-engaging with a cross section of one’s colleagues, old and new, at the beginning of the year*), and on a third hand (sorry) there’s been a big crunch on the research side of things. The big crunch saw me in my office until about 3:00am after a long night of finishing up two companion papers with three of my students (this included breaking for a walk across campus at about 8:30pm to get some tasty mulitas at the excellent La Taquiza) and submitting them to the arXiv. Sensibly, the students went home by 1:30 or so, leaving me the silly one to tinker some more until the end. It was a really fun couple of projects uncovering some rather rich physics, and I’ll try to tell you about them some time soon.

So anyway, my plan today was to write you a 9/11 post, but not quite about what you Click to continue reading this post

Origins of a Species-Killer?

In case you missed this earlier this week, there was an intriguing detective science story that, if correct, has yielded remarkable news about the past of our planet, and of course, us. From an AP story by Richard Ingham (via Yahoo):

asteroid collision event simulationThe extinction of the dinosaurs 65 million years ago can be traced to a collision between two monster rocks in the asteroid belt nearly 100 million years earlier, scientists report on Wednesday.

The smash drove a giant sliver of rock into Earth’s path, eventually causing the climate-changing impact that ended the reign of the dinosaurs and enabled the rise of mammals — including, eventually, us.

(Image above: Simulation images (AFP/HO/Don Davis) of the asteroid collision event, and the resulting extinction collision event on earth, and the collision with the moon.)

The scientists are William Bottke, David Vokrouhlicky and David Nesvorny, working at the Southwest Research Institute in Colorado. They traced the rock to a collision event that took place in the inner parts of the asteroid belt somewhere about between 140-190 million years ago, producing the family of fragments collectively called the Baptistinas, the largest being Baptistina 298. Over time, some of the fragments found Click to continue reading this post

The Green Room

Here’s another image or two that I captured for you of the very large and dramatic pieces of Dan Flavin. This is from my July visit to the Los Angeles County Museum of Art’s (LACMA’s) retrospective of his work. You’ll recall the two earlier posts here and here. (Click them to enlarge.)

dan flavin retrospective  -green

It is easy to dismiss these as very simple coloured baubles writ large, and that would be a mistake. I’m sure that the artist was very aware of one hugely striking thing that one cannot convey in the photographs, and that is the powerful effect the presence of one single striking colour can have on one’s feelings. The intense blue from a previous work I spoke of was remarkable, and then shortly afterward you come to this giant Click to continue reading this post

Vélib Works!

velib bike from parisSo far. I forgot to point this out a couple of weeks ago. There was a nice story in the Guardian giving a one month update on the progress of the Velib program in Paris. Recall I blogged about its launch here, and expressed hope that the expectations that it would not work were wrong (I’m such an optimist). Well, the news is that it is working! The whole article (by Angelique Chrisafis) is here. A quote:

Day and night, tourists, commuters and returning party animals cruise by on the chic new machines. People have joyfully discovered the cheap new way of exercising en route to work or getting home drunk after the metro closes, hence a rush of hires after 1am. There’s a glut of bikes deposited at stands at the bottom of hills and none left at the top, as people freewheel down from the heights of Belleville and Montmartre.

(Now I’m in the mood to get out the wonderful movie “Les Triplettes Des Belleville” (or “Belleville Rendezvous” or “The Triplets of Belleville”) for an enjoyable evening.) Further:

Click to continue reading this post

Categorically Not! – Mistakes!

Julia Sweeney during a Categorically Not! eventThe next Categorically Not! is Sunday September 9th. The Categorically Not! series of events that are held at the Santa Monica Art Studios, (with occasional exceptions). It’s a series – started and run by science writer K. C. Cole – of fun and informative conversations deliberately ignoring the traditional boundaries between art, science, humanities, and other subjects. I strongly encourage you to come to them if you’re in the area.

Here is the website that describes past ones, and upcoming ones. See also the links at the end of the post for some announcements and descriptions (and even video) of previous events. (Above right: Julia Sweeney performing an extract from her play “Letting Go of God”, in the event with the theme “Uncertainty”.)

The theme this month is Mistakes! Here’s the description from K C Cole:

Blunders, boo boos, bloopers, errors, slip-ups, goofs, misinterpretations and misunderstandings. Everyone makes mistakes. In science, the notion of “mistake” is often itself misunderstood. Frequently, a “mistake” often turns out to be nothing more than a limited or skewed perspective. Or as Einstein put it, discovering a new theory is not so much like tearing down a house to build a new one as climbing a mountain from which one can see farther; the old “house” is still there, but is seen in a vastly different context. Mistakes in personal life and Click to continue reading this post

Funky Hideaway

lost souls cafeI love downtown Los Angeles. No two ways about it. It’s rapidly getting better, as you may have heard, and there are so many interesting things to find down there. I hope to do a report sometime on an extended walkabout I did down there last month, but that’s for another time. It is also great to cycle around, as I do quite a lot.

Today, still in the heatwave, I left campus to go and hide downtown, first stopping by the excellent Grand Central Market for a bit of shopping for ingredients for a special dish I am going to prepare for a Salon-style gathering at some friends’ on Saturday. More on that later. Then I went to work in one of my favourite cafes in the city. I shouldn’t give away my hideouts, but there’s only you and me reading, right?

It’s the Lost Souls Cafe, hidden down an alleyway (Harlem Place Alley) off fourth street between Spring and Main. Perfect for the subway at Pershing Square, and one of the few non-bar type places open until 10:00pm downtown. (Wish it would go until 1:00am or so.)

It’s a fantastic place, as you can see from their website, but relatively few people that Click to continue reading this post

Clouds at Will

This is simply fascinating to see for so many reasons. Will Campbell (over on his blog [sic] – see the posts here and here for background), who has been doing some fun experiments with his camera and computer to make time-lapse photography (you’ll recall an amusing one from before) has captured an entire day of cloud formation in the skies above some mountains near Los Angeles during the heatwave day of Sunday.

Click the still to go to the site with the movie (or find it at YouTube here):

wildbell clouds

It is both beautiful, interesting (scientifically and otherwise) and frustrating (why don’t Click to continue reading this post

Paneful Jigsaw

Temperature update: Going to be 106oF today. I think at 7:30am when I got up today it was already in the mid 80s (although that might have been partly due to reduced airflow indoors – I had to rush outside to take a deep breath). Gosh.

window shatter pattern
Above is part of a puzzle I was working on for a while on Saturday. A more detailed and larger image will follow below. I did pretty well, but then I got distracted after a while (see below). The last puzzle pieces came from (I suspect) a single puzzle piece shattering in a secondary event. The primary event? Bit embarrassing. I was preparing dinner on Thursday night, a guest was about to arrive, and a fly entered the kitchen. I hate flies in my kitchen at the best of times, and this was just too much. I tried to open the window to encourage the beast to depart, and it refused. I tried to open the window further and exasperatedly wafted my hand in its direction to scare it off the window pane, misjudged that action and pushed my hand through the window. Felt like a real idiot, of course: An expensive mistake, an awkward thing to explain, and of course a million flies and other creatures now had unrestricted access… The good news is that I only got a slight nick from the razor sharp edges, my guest did not think I was too insane (or no more than I usually am) and dinner was tasty. So all’s well that ends well.

The next morning I woke up and immediately thought “I can’t believe I put my hand through my window”. Went downstairs to check. Yes, it was true. There was a nice shatter pattern (notice the cracks radiating outward from the reconstructed impact point – see photo and discussion below) to admire, and lots of bits of glass on the Click to continue reading this post

Good Luck Brittney Exline!

Just spotted this AP article (by Kathy Matheson) about Brittney Exline:

brittney exline[…] at the age of just 15 she is beginning her Ivy League career Wednesday when classes start at the University of Pennsylvania.

Which is very good indeed, but I was especially pleased to see:

She excels at math and science and is really interested in politics, so she enrolled in a Penn program that will award her degrees from both the engineering and liberal arts schools when she graduates in 2011.

Hurrah!

Have a look at the AP story for quotes, information about her background, other Click to continue reading this post

Have One for Michael Jackson

I’ve got to cross town later on to Pacific Palisades to a party, and while I’m keen on the party, I’m not keen on the journey – It is super hot outside, and I have to go via Santa Monica to pick up some tarts to take along1. Temperatures are sure to go over 100oF again today, and so everyone and their dog will be heading West to the beach.

I was about to begin my morning mission to get supplies for the party, and I heard that Michael Jackson died last week. Not that Michael Jackson, the other one (see below). It’s quite a coincidence, since I was particularly on the prowl for two of my favourite Belgians, Duvel and Hoegaarden, and maybe one of the excellent Sam Smith’s stouts (from England). I was successful. (The excellent Bev’ Mo’ was well-stocked, and I was the first in the door when they opened.)

some excellent beers
(If I may be so bold, you don’t really understand what beer can be if you have not tried Belgian beers. They’re the finest makers on the planet, without a doubt (others may disagree). Even if you think you don’t like beer, there’s probably one they produce that you’d like. The two on the right are among the easier to get favourites from there. Drop what you’re doing and rush out and get some. Go! Now!)

Still don’t know who I’m talking about? There’s a Washington Post article by Adam Click to continue reading this post

Lookin’ For Some Hot Stuff

___________________________________________________________________________________
Hot, hot, hot, hot stuff
hot, hot, hot
hot, hot, hot, hot stuff
hot, hot, hot

– from “Hot Stuff”, by Donna Summer (1979). I refer to not only the physics but the c. 100 oF temperatures we’ve been having here every day recently.
___________________________________________________________________________________

On my way back from the conference, I spotted this book (below left) last Saturday in Foyles (the booksellers) in London1. Quark Gluon Plasma book It is a collection of reprints of a lot of the papers forming the foundations of the physics of the quark-gluon plasma (QGP) idea, going back the early to mid 1970s with such papers as Collins and Perry (Gosh, I had no idea Malcolm was one of the early workers on this idea. He’s much more thought of as associated with black holes, gravity, strings and so forth, ideas which – ironically – have recently turned out to be relevant to the discussions of the physics too. See my recent post, and there are also various popular articles to be found2).

Putting aside the usual ridiculous price that Springer Elsevier charges for books, I found myself in two minds about this book, in view of the surprises being uncovered about the properties of this remarkable state of matter at the RHIC experiment. Is this collection of early papers a useful working tool, or is it now just of historical interest, since many of the basic expectations about the properties of the plasma seem now to be incorrect?

rhic collision of gold ionsWell, after a bit of thought, I decided that the latter view would be way too hasty. First and foremost, on a general level, even if some of the computations in some papers were done in the “wrong” light (it’s a strongly coupled liquid that flows, not a weakly coupled gas of quarks and gluons), much of their content will still be useful in many ways – good and correct calculations last for all time, it is the sense of the words decorating them that may crumble over time. More specifically, one can worry about whether there were assumptions (and approximations based on those) that went into Click to continue reading this post