Tuesday, April 29, 2008

OCIAM to fund research on camel-spitting distance

Update (6/26/08): Enough time has passed, so I put the correct 2008 posting year back in.

Note (added 4/30/08): This is actually a blog entry from 4/29/08, and I am burying it elsewhere on this page by request.



Remember that a few weeks ago I wrote this blog entry, which I then relegated to a "2007" post with a date change until it was safe to announce things officially. (I'm sneaky that way.) Well, I have now been given word that the news can be made public. So here goes.

I'll start with the official words from our research facilitator:

I'm delighted to announce that the department has just been awarded $25M
by the Global Research Partnership of the King Abdullah University of
Science and Technology to set up the Oxford Centre for Collaborative
Applied Mathematics (OCCAM), to be run in the first instance by John
Ockendon and 6 collegues drawn from OCIAM, CMB, Numerical Analysis and the
Computational Biology Group.

The Centre will be based in the Gibson Building and will have 4 new
faculty, 4 research fellows, 16 PDRAs and 14 graduate students. It will be
formally launched on 1 Oct 08.

We will be making a presentation on 16 May in the Industrial and
Interdisciplinary workshop slot to describe what'll be happening with
OCCAM and how you can get involved. I hope everyone will be able to come
along.



Now that we're getting funding from Saudi Arabia, there are going to be a few changes around here. For example, here are just a few of the new topics from which the newly-hired researchers will be allowed to choose:

1. Optimization of camel dynamics (including the kinematics of spitting).

2. Modelling oil extraction.

3. Optimal design of chadors.

4. Community detection in terrorist networks


Now let me be a bit more serious for a second. I have mixed feelings about this whole thing. While it's really exciting to be in a research group (especially one in mathematics) that is getting a grant of this magnitude and it will be "intellectually awesome" (to borrow some old phrasing from the efforts to get the grant and twist it slightly) to have lots of new faculty, postdocs, and graduate students around, there are some very serious ramifications. One of Oxford's student newspapers had an article last term about various programs here that have gotten money from sources that could be construed as dirty. Presumably, we will be henceforth be included on this list, so I expect that there will be at least some political backlash to this funding that the Powers That Be in our group will just have to deal with however they see fit. This new grant also has the potential to have ramifications on the politics within the group (and I have seen some signs of this already), so we're all going to have to work hard to make sure things remain pleasant in this respect. (One of the things that I like best about OCIAM is how much everybody seems to like each other.) I am not one of the central players on this grant, and right now my plans are to remain on the periphery. I will certainly interact with the new people we hire (and people already here, of course), but I currently don't feel comfortable accepting any money that percolates from this grant. I haven't decided for sure if I won't ever accept any, but I am definitely leaning against it. At the very least, I would have to think very seriously about the decision. Part of my discomfort certainly comes from my Jewish ancestry, and while my religious beliefs (obviously) differ greatly from what is "expected" of me, I have enough of a connection to my background that I wouldn't be able to accept funding from the source in question without serious thought/soul-searching. To be fair in my discussion, I should also mention that the grant has the potential to do a lot of good---and not just for the research group I'm in. With this grant, Oxford has been selected to help found a Western-style applied mathematics group in Saudi Arabia, so my colleagues have the chance to play a leading role in bringing something potentially very important to that country.

In closing this entry, let me recall for some of you that Arcane Gazebo jokingly phrased his decision to go into finance as "selling out". I hereby raise my plastic cup (with the remnants of this morning's iced latte, of course) in the fervent hope that we haven't done just that. I plan to be a passive observer in this whole thing (with a slight amount of "mo' money" attitude with respect to what OCIAM is getting) and look forward to the significant side scientific benefits from the additional academics that will be buzzing around the place. But it's also worth mentioning that I'm extremely glad that I'm not a central player in this grant and most definitely plan to remain that way. Maybe I'll change my mind later, but right now I feel like I can't accept any of the money that comes through this grant (which means, in practice, that I will make no attempt to fund any of my grad students or postdocs through this mechanism).

Now, in which direction am I supposed to bow? I can never get that straight.

Did I mention that most parties around here are costume parties?

Lemming just e-mailed me about the following article on BoingBoing:

"Citizens observed a masked individual wielding a running chainsaw walking around Bicester, Oxfordshire, England. Turns out he was on his way to a costume party."

I think I might have mentioned this before at some point, but nearly all of the student parties around here are (de facto) costume parties. This is a bit different from what I was used to before I moved to Oxford. Of course, most of the costumes I've seen aren't particularly creative... (Part of me is a bit disturbed by the choice of costume, but a larger part of me is amused by it. I suppose that's in poor taste, but I'm not going to lie to myself and pretend I'm not amused.)

Monday, April 28, 2008

Mathematical Genealogy WebApp

Courtesy Tim Chartier, I just found out about a WebApp that creates a tree with one's mathematical genealogy on the fly. I approve!

Here is my mathematical genealogy.

That about sums it up.

In honor of Travis's move to New York ("That really chaps my hide!"), here is an old New Yorker cartoon that summarizes the superiority complex of New Yorkers (pronounced along the lines of "New Yawwwwkaahs") quite nicely.

I never actually saw this cartoon before (it was used in a Shysterball blog entry to which Rob Neyer linked today), but it is a thing of absolute beauty.

Some classic baseball tirades

I was reminiscing about some classic baseball tirades (especially several courtesy of former Dodger manager Tommy Lasorda), so I went to YouTube to find links to some of them.

For your listening pleasured, here is an audio medley of Lasorda going berzerk. There are a few classics missing, but his opinion of Kingman's performance and his comments about Kurt Bevacqua (and a few other famous clips) are all there. The pictures that accompany the medley are occasionally apropos.

Here is also a famous tirade by Lee Elia that starts in the middle, but has the best parts. For a complete description of this tired (and the unbleeped text) see the first book by Jay Johnstone (a former baseball player). This book had some problems with censorship because it included this...

I also tried to find a video of the famous battle of Carlos Perez versus the dugout watercooler on YouTube, but I wasn't successful. I remember seeing this live, and this is one is a beauty. If any of you ever find it posted online, please send me the link.

Update (4/29/08): Today is actually the 25th anniversary of Elia's tirade. This anniversary hadn't registered when I wrote this blog entry.

Sunday, April 27, 2008

A Quick Summary of Oxford

The weather has gotten really nice the past few days, so now when I walk by the Somerville quad to get back to my apartment, I see lots of students hanging out outside. At Caltech, I would expect to see some of them playing frisbee (which is what this type of weather puts me in the mood to do... let's play when I visit in a couple of weeks!), and admittedly I have seen them toss a frisbee on the quad before. The last couple of days, however, I have seen people playing croquet in one of the side lawns of the quad. Somehow this corresponds quite closely to my stereotypical vision of Oxford.

(I actually played croquet a couple of times when I was really young, and I would definitely be up for doing that again--even if I have to use a mallet rather than a local flamingo.)

In other news, there seems to be something rather hornet-like in my apartment at the moment. Sigh... I opened my window in the hope that it will leave, but that could easily backfire.

Anyway, back to work... (Oh, and the rant is still coming.)

Saturday, April 26, 2008

Proverb of the Day

Today's proverb comes from Frank Herbert's Dune (which I have finally gotten around to reading... it's certainly taken long enough), although I assume variants of it have appeared forever.

The quote is: "Any road followed precisely to its end leads precisely nowhere."

Comment: Amen!



P.S. The rant is still coming. I've been busy and haven't wanted to write long blog entries.

Wednesday, April 23, 2008

Things that don't make sense

I can't understand the strange fascination the people of this country have with mayonnaise. What the fuck?

P.S. The rant is coming. I've just worked too many hours today to want to type this up at the moment, but it's coming. (And the Dodger game will be on soon anyway, and I'm not going to choose ranting over watching the Dodgers when it would probably serve me well to calm down anyway.)

Update: The Dodgers are not playing on the east coast tonight, so the game is too late for me to watch. I'm still not in the mood to type up a rant. My MLB video service is crapping out at the moment (which I think has something to do with the Realplayer update I downloaded earlier today), but am I am inclined to play some Smash Brothers anyway. I tried fighting this for a while, but I need to get up early tomorrow, so I think I'll just read some baseball articles and crash. I'll try fighting this tomorrow.

Tuesday, April 22, 2008

Tales from the arXiv: Impact factor edition

Here is an abstract, just posted on the arXiv, that attempts to analyze the inflation in journal impact factors over the years:

arXiv:0804.3116
Date: Sat, 19 Apr 2008 00:17:22 GMT (995kb,D)

Title: Differences in Impact Factor Across Fields and Over Time
Authors: Benjamin M. Althouse, Jevin D. West, Theodore Bergstrom, Carl T.
Bergstrom
Categories: physics.soc-ph
Comments: 9 pages, 3 figures
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
\\
The bibliometric measure impact factor is a leading indicator of journal
influence, and impact factors are routinely used in making decisions ranging
from selecting journal subscriptions to allocating research funding to deciding
tenure cases. Yet journal impact factors have increased gradually over time,
and moreover impact factors vary widely across academic disciplines. Here we
quantify inflation over time and differences across fields in impact factor
scores and determine the sources of these differences. We find that the average
number of citations in reference lists has increased gradually, and this is the
predominant factor responsible for the inflation of impact factor scores over
time. Field-specific variation in the fraction of citations to literature
indexed by Thomson Scientific's Journal Citation Reports is the single greatest
contributor to differences among the impact factors of journals in different
fields. The growth rate of the scientific literature as a whole, and
cross-field differences in net size and growth rate of individual fields, have
had very little influence on impact factor inflation or on cross-field
differences in impact factor.
\\ ( http://arxiv.org/abs/0804.3116 , 995kb)


If I am interpreting this abstract correctly, the authors of this paper seem to be concluding that the differences one sees between fields is predominantly the result of which journals reporting venues (in this case, Thomson Scientific's Journal Citation Reports) choose to index. In other words, they conclude that the dominant factor is basically noise at best and corruptible choices at worst. That's just lovely. (I haven't read the paper, so I am offering no opinion as to whether I agree with the authors' conclusion. I'm just saying that this is an extremely disturbing conclusion.)

Monday, April 21, 2008

Turning Cheese into Steak

You know how you hear or read about various amusing incidents about people like Richard Feynman or other famous scientists that become an integral part of their legendary status? Some of these incidents arise from things they do on purpose, and others arise completely by accident. I've occasionally done things that could potential be construed to be in both of these categories, though I unfortunately (fortunately?) don't have the scientific reputation for them to propagate that far. (That said, one of my practical jokes did get brought up by a faculty member during my University of Maryland interview in 2006... The scientific world is a rather small one...) Also, I think it's often true that the unintentional incidents are often the ones that make the best stories. Sometimes you just need the right mix of personality and circumstance for magic to happen, and that brings me to Wednesday night. But first, a long precursor is in order:


Back in the day (late February 2006), we had a discussion on Arcane Gazebo's blog about the notion of entanglement and food perhaps being in a superposition of a salad and a steak. The particular blog entry that I have in mind included a link to this particular post on Cosmic Variance.

This is a rather long aside, but let me quote the relevant passage from Cosmic Variance:

Fortunately, we are not only very considerate, we are also excellent experimental physicists with a keen grasp of quantum mechanics. Quantum mechanics, according to the conventional interpretations that are good enough for our purposes here, says three crucial and amazing things.

First, objects can exist in “superpositions” of the characteristics we can measure about them. For example, if we have an item of food, according to old-fashioned classical mechanics it could perhaps be “salad” or “steak.” But according to quantum mechanics, the true state of the food could be a combination, known as a wavefunction, which takes the form (food) = a(salad) + b(steak), where a and b are some numerical coefficients. That is not to say (as you might get the impression) that we are not sure whether the food is salad or steak; rather, it really is a simultaneous superposition of both possibilities.

The second amazing thing is that we can never observe the food to be in such a superposition; whenever we (or sleeping puppies) observe the food, we always find that it appears to be either salad or steak. (Eigenstates of the food operator, for you experts.) The numerical coefficients a and b tell us the probability of measuring either alternative; the chance we will observe salad is a2, while the chance we will observe steak is b2. (Obviously, then, we must have a2 + b2 = 1, since the total probability must add up to one [at least, in a world in which the only kinds of food are salad and steak, which we are assuming for simplicity].)

Third and finally, the act of observing the food changes its state once and for all, to be purely whatever we have observed it to be. If we look and it’s salad, the state of the food item is henceforth (food) = (salad), while if we saw that it was steak we would have (food) = (steak). That’s the “collapse of the wavefunction.”



Now let's revisit Wednesday night, which was the special dinner at a really fancy restaurant for a workshop that CABDyN (Oxford's complex systems group) was hosting. Because of emergency grant proposals, other things that cropped up last week, and the need to spend at least one day (Friday) revising a draft of a paper before the term officially started, I was unable to go to the workshop as well. I was asked to go to the dinner anyway (even though I felt guilty), so I went---although I was in quite a lousy and antisocial mood that night. Some of the attendees didn't seem to like the fact that I was at the conference dinner even though I wasn't going to the rest of the workshop (and, as I mentioned, I did feel somewhat guilty about it), but that's not the story I want to tell.

The main course was some cheese thing-- a cheese souffle, I think. I don't like cheese. I will typically entirely avoid food that has any cheese on it (except for cream cheese, which has a rather misleading name anyway--it's not the same thing) and when there is some, I will scrape it off as best as I can before I eat the rest of the food. Some people reading this have seen me in action with a slice of cheese inadvertently ends up on a hamburger, etc. I had already declined the previous course because it didn't look appealing, and as those who know me even moderately well are aware, I am a very picky eater and simply won't eat something that looks completely unappealing to me (or that has things in it I don't like, etc.). OK, so then the main course comes and it turns out to be the cheese souffle; we're all supposed to eat vegetarian or something. I found out what was inside the object and--knowing that I wasn't going to eat it at all--I asked a waiter to take it back because I didn't want to waste it.

When the waiter came back, without my asking he told me about a couple of items that could be made on short notice. He then brought back a menu (well, he told me first without the menu, but I asked to take a look at the menu anyway) and pointed out those items again. Note that I did NOT ask any of the waiters to do this... I was just planning on getting food on my own later, but given the offer and because one of the items that could be made was a steak, I went for it. They said they would just charge it to the account being used to pay the bill, so I memorized the price so that I could e-mail the dinner's organizer when I got home to offer to pay for my food because I simply wouldn't have been comfortable not doing that. (The organizers refused to accept my money.) But anyway, I had a really good steak (the best I've had in the UK, actually) while everybody else (maybe 60 or so people) had to eat vegetarian--and it was purely by accident. In short, I figured out how to turn cheese into steak (but without the entanglement).

A couple of the people at my table seemed kind of annoyed at this, and the whole thing was apparently a hot topic at the workshop the next day.

I think it's safe to say that I have added to my legendary status. As I mentioned, all it takes is a combination of personality and circumstance. One doesn't need to actually try to do anything. As Lemming mentioned by IM, "You're going to have a beautiful eulogy."

Saturday, April 19, 2008

RIP Edward Lorenz (1917-2008)

Lemming just let me know that Edward Lorenz, whose pioneering paper on chaos (although that term had to wait a few years for Li and Yorke to invent it) in weather prediction led to coining the term "the butterfly effect", died on April 16th. Among other things, this led to a lot of work on what is called the Lorenz attractor (one of the most famous examples of a chaotic attractor).

One thing that's worth noting is that the obituaries are incorrectly crediting Lorenz with having discovered chaos. Henri Poincare' had already discovered it--without the benefit of computers!--quite a few years before.

Vortex Lattice Locking in Two-Component Bose-Einstein Condensates

This is the title of my new paper that just came out. You can find a link here.

Unlike most of my papers, this one is very condensed-mattery (to invent a new word... think of it the way you would use the word "buttery") and doesn't have much mathematics at all. I do spend a lot of time working on condensed matter physics problems, but the style of my papers ordinarily reveals my nonlinear heart (or, rather, my nonlinear science/applied math heart). This particular paper was written jointly with my fellow scientists in Caltech's theoretical condensed matter group, and the flavor of the paper is correspondingly different---it's most definitely a physics paper rather than an applied math paper.

The first author is Caltech postdoc Ryan Barnett. Also on the list are Caltech faculty member Gil Refael and non-Caltech condensed matter theorist Hanspeter buchler (who goes by Hans Peter in publications).

Here is the abstract:

The vortex density of a rotating superfluid, divided by its particle
mass, dictates the superfluid’s angular velocity through the Feynman relation. To
find how the Feynman relation applies to superfluid mixtures, we investigate a
rotating two-component Bose–Einstein condensate, composed of bosons with
different masses. We find that in the case of sufficiently strong interspecies
attraction, the vortex lattices of the two condensates lock and rotate at the drive
frequency, while the superfluids themselves rotate at two different velocities,
whose ratio equals the ratio between the particle masses of the two species.
In this paper, we characterize the vortex-locked state, establish its regime of
stability, and find that it survives within a disk smaller than a critical radius,
beyond which vortices become unbound and the two Bose-gas rings rotate
together at the frequency of the external drive.


I view this as a form of synchronization, but instead of the better-studied frequency-locking, one actually needs to take the different masses of the species into account (it's a momentum-locking). One of the very important points we make is that if you look at a lot of papers, you'll see that they assume that two different masses are the same "without loss of generality" (and the literature on multiple-component Bose-Einstein condensates is absolutely riddled with that assumption). Of course, as we show in this paper, that's just not true, as there are very interesting phenomena that you'll simply miss if you always make that assumption.

Friday, April 18, 2008

Reversing the Curse of the David Ortiz Jersey

The Onion recently published this article about the Yankees' attempt to reverse the recent curse of the buried David Ortiz jersey.

How did they do it? Simple. They buried former Yankee Bernie Williams for good luck. The article describing the details is absolutely hilarious.

(I found out about this article from Rob Neyer's blog.)

Thursday, April 17, 2008

Caltech pitcher sets hitting record

As described in The California Tech, a Caltech pitcher recently set an NCAA hitting record.

How did he do this? Simple... he hit 13 batters in a 6-inning performance. I approve! :)

Tuesday, April 15, 2008

RIP John Archibald Wheeler (1911-2008)

I found out from a colleague at dinner tonight that John Archibald Wheeler died on Sunday. Here is a link to an obituary published by the New York Times.

Among other things, Wheeler coined the term 'black hole' and coauthored the monstrosity of a book called Gravitation that has been used as the Physics 236 textbook at Caltech for years and which really needs to be updated. (He did a lot of pretty good science too...) He also co-wrote an elementary special relativity textbook that I used as a frosh. The explanations in that book were generally good, but the presentation of the problems was often rather long-winded (it was sometimes difficult to find the question amidst all the text) and he and his coauthor used made the absolutely retarded choice of called the "momentum-energy 4-vector" (which would be more accurately called a "tensor" anyway) as the 'momenergy' 4-vector. WTF! That remains one of the most retarded terms I have ever seen applied to a scientific object, so I guess he was just trying to make up for black hole. (Given that Ben Miller was a fellow Lloyd frosh from my year, this naturally led to lots of comments involving 'mom' and 'energy.')

Monday, April 14, 2008

Math license

Courtesy Justin, here is an XKCD comic about revoking one's math license. I approve!

Giants band together to score run

On his blog today, Rob Neyer linked to a hilarious article in The Onion entitled San Francisco Giants Band Together To Score Run.

It's a short article, so I'll just reproduce the text below:

MILWAUKEE—The San Francisco Giants put aside their differences Sunday night, working together as a team in a common effort to score a run in a baseball game. The scrappy nine-man crew overcame daunting odds to cobble together the run, as each player used his individual strengths and skills to help string together an unlikely series of events—including a walk, advancement on a wild pitch, an infield single, and perhaps most selfless of all, a ground into double play—that ultimately resulted in a Giant crossing home plate. "This just shows you what a team can do when they put their mind to it," said Giants first-baseman Dan Ortmier, who was swarmed by his celebrating teammates at home plate after scoring the run. The Giants lost to the Brewers 12-1.


(Granted, we're not exactly doing better at the moment, but the article is nonetheless awesome.)

Sunday, April 13, 2008

Digging for Jerseys

Here's a really neat story.

Apparently, one of the construction workers who worked on the new Yankee stadium is a Red Sox fan and buried a David Ortiz Red Sox jersey amidst the concrete foundation of the stadium in order to curse the Yankees. The jersey was recently excavated.

Anyway, I approve! It's the type of vignette that would be great to see in a baseball movie.

Another Bulwer-Lytton entry

Inspired by a failed analogy in an expository article I'm currently writing about the FPU problem, I devised (and have since submitted) another entry for the Bulwer-Lytton bad fiction contest:

As predictable as the regular dynamics of a periodic trajectory in a completely integrable system, James Bond had ferocious, passionate sex with the seductive, evil temptress repeatedly (although one major difference is that inverse scattering theory can be used to understand the former situation but not the latter).

This sentence is actually completely accurate mathematically!

(By the way, my failed analogy is that I tried to give my readers intuition about regular dynamics by comparing their predictability to James Bond movies. One of my coauthors pointed out that analogies only help when they actually increase understanding, though he phrased things much more tactfully than that. My attempt to explain why the standard superposition principle doesn't work for nonlinear problems using the double suicide in Romeo and Juliet was even worse.)

Thursday, April 10, 2008

RIP Boris Chirikov (1928-2008)

Here's another death I missed, and in this particular case I am very surprised that it escaped my notice. On February 12th, Boris Chirikov, one of the founding fathers of both Hamiltonian chaos and quantum chaos, died. I got my Ph.D. thesis in quantum chaos, and of course this blog is named after that field. I continue to do research in both of these subjects, which are near and dear to my heart. Among Chirikov's contributions to these fields are his development of his eponymous Chirikov overlap criterion (which played an important role in the investigation of chaos in the Fermi-Pasta-Ulam problem and describes the transition from locally chaotic dynamics to globally chaotic dynamics) and equally eponymous Chirikov-Taylor map (aka, the "standard map").

Update: Here is a link to the obituary in the online version of Physics Today.

RIP Arthur C. Clarke (1917-2008)

With all the attention I've been paying to research, baseball, and Super Smash Brothers Brawl, a few things have flown under my radar---like the fact that Arthur C. Clarke died on March 19th. I actually founded out about his death from the notices listed in the online edition of Physics Today.

For many years, I have frequently tried to find times to interject variants of "I'm sorry Dave. I'm afraid I can't do that." into conversations.

Tuesday, April 08, 2008

Tales from the arXiv: Even more baseball

The following abstract got posted to the arxiv this morning:

Can one understand the statistics of wins and losses of baseball teams? Are their consecutive-game winning and losing streaks self-reinforcing or can they be described statistically? We apply the Bradley-Terry model, which incorporates the heterogeneity of team strengths in a simple way, to quantify the rank dependence of the average number team wins and losses in major-league baseball over the past century, and also to argue that long winning and losing streaks have a purely statistical origin. The data further show that the past half-century of baseball has been more competitive than the preceding half-century.

The authors are C. Sire and S. Redner.

You can find the paper here.

Monday, April 07, 2008

Corridors and Fingernails

I have spent a decent bit of time wandering the corridors of Heriot Watt buildings trying to find cafeterias, bathrooms, exits, and the like. Why do they design their buildings like mazes? They make Sloan Annex and even Dartington House seem easy to navigate. (Yes, the last two buildings in which I have offices are both rat mazes. That says something about my lot in life, doesn't it?)

Also, I am the early leader in our brand-new Study Group injury pool. I managed to savage one of my fingernails trying to lift an empty lunch tray (in fact, two empty lunch trays). Ouch!

This conference also has its version of Housequotes, which are apparently supposed to be collected for a final presentation on Friday. These objects are described in this article. I already uttered a comment about the well-known "vegetable kingdom" that may or may not have any staying power.

Oh, and I found out a paper on which I played an ancillary role as a grad student apparently just got published in a collection---only 6 years after I ceased to have any involvement in it. I always just thought it was going to just remain a preprint, but I think the book ended up being partly a conference proceedings for a conference from back then where one of my coauthors presented the paper. I got an e-mail about it today, and this was a paper that had been out of my radar for so long and to such an extent that I hadn't even included it in my CV since before my first postdoc.

Sunday, April 06, 2008

Well I just started the trip off right...

I really needed to use the bathroom and searched all around both my floor and the bottom floor of the building in which my room (a dorm room) is located and tried to find a single bathroom without success. This building is a maze, though I did manage to find a key to indicate what rooms corresponded to bathrooms. Unfortunately, all of them were unlabeled and there didn't seem to be any rooms at all in the physical locations that were supposed to correspond to bathrooms. I did find a couple of random things, but none of them were the bathroom I was seeking.

As it turns out, I missed the bathroom that was located in my room. (The entryway to the room covers it when one opens the door.) Oops.

I can tell already that I'm going to be extremely helpful for the mathematical modeling problems this week---especially when it comes to finding efficient (or, day I say, optimal) solutions.

Once again I have proven that I am a theorist...

What happens in Edinburgh stays in Edinburgh

In about an hour and a half, I will be boarding a train to Edinburgh to attend a study group with industry at Heriot-Watt University. There are direct trains from Oxford to Edinburgh, and my choice of the 1:36 train is so that I can have a route with 0 layovers. Then I can just chill in the train for a while and not have to pay attention at all if I don't want to.

This trip will include several firsts for me:

(1) It will be my first time in Edinburgh, which is where solitons were first observed. It's supposed to be a really nice city, and I bought new film and a new battery for my camera in preparation for it. (Note that I will finally get off my ass and buy a digital camera, which I've been intending to do for several years. I can be really lazy about things sometimes... I'm waiting until I'm in the States in May because it will cost me half as much if I buy it while I'm back home.)

(2) This will be my first time in Scotland. I am gradually visiting new countries. I'll also knock off Italy later this summer.

(3) This will be my first study group. On the first day, six industry groups will present their problems, and the attendees will spend the rest of the week seeing how far they can get on them. It should be very cool. I never got a chance to participate in the Mathematical Contest in Modeling, and this has that kind of flavor. Besides working on interesting problems, this has the chance to lead to data sets and longer-term projects and collaborations. It's an excellent opportunity and it gives me the chance to spend a few days away from home during the break (which in general is quite revitalizing). The problem that interests me the most based on the online descriptions is one involving recommendations for items with few reviews---essentially, it's difficult to deal with those kinds of tails because of small sample sizes, so the plan is to try to come up with clever ways of dealing with that. From my perspective, this is a networks problem and, in fact, I believe several of these issues have been studied in past papers that use, for example, data sets from Amazon's recommendation system. Plus I can see how the various Netflix prize solutions have dealt with similar issues.

Friday, April 04, 2008

This can't be good.

In my bathroom I just noticed what appears to be a hornet. I can't believe those bloody bastards followed me to England! I probably brought those fuckers into the country with me.

For the locals who don't know, I have a bit of a history with hornets.

Shit.

Pitchers in the Outfield

As Zifnab mentioned via IM and Rob Neyer discussed in his blog, Braves manager Bobby Cox pulled some interesting shenanigans in last night's game against the Pirates.

As described on a blog called Baseball Toaster, "With runners on first and third and one out in the top of 10th in Atlanta, Bobby Cox replaced pitcher Chris Resop with Royce Ring to pitch to Adam LaRoche. Resop moved to left field to replace Matt Diaz. After Ring struck out LaRoche, Resop moved back to the hill to face Xavier Nady. Gregor Blanco then entered the game as the new left fielder."

As discussed on Baseball Toaster, moves like this actually have a long history. I vaguely recall the 1986 Mets example that Baseball Toaster mentions. Pitchers have also shown up in outfields or other positions for different reasons. Eric Gagne played a little center field a couple of days ago, and I'm guessing that the Brewers are probably carrying 12 pitchers and ran out of position players. In games with many extra innings, one will occasionally see some really cool stuff like that. Here's one of my favorites: Years ago, in an extra inning game, the Cardinals had Jose DeLeon switching repeatedly with Tom Brunansky over who was in right field and who was in left field. Basically, the manager wanted Brunansky (a natural outfielder) to be the more likely guy to field the ball, so he was in right whenever a lefty was up and in left whenever a righty was up. They ended up switching every batter, so the announcers were like "Brunansky to left, DeLeon to right." And then one batter later it was "Brunansky to right, DeLeon to left."

There are some other classy ones. The Dodgers lost a game in inning 21 (I think it was 21) in 1989 (I think it was 89). The losing pitcher was third baseman Jeff Hamilton. First baseman Eddie Murray was at third base when the game ended, and pitcher Fernando Valenzuela finished the game at third. (Now we just need an extra inning game where Chin-Lung Hu moves around the field a lot...) More recently, Rockies catcher Brent Mayne actually earned a victory when he finished the game on the mound.

Thursday, April 03, 2008

More on Smash Brothers

I've continued to play lots of Super Smash Brothers Brawl. In many respects, it's more of the same from Super Smash Brothers Melee, but in part that means more fun, though there are lots of new things too---such as new characters, an adventure game that reminds me of things like the old Teenage Mutant Ninja Turtles games, and a very cool way to do unlockables by hinting what else one might get based on doing certain things. And, as I mentioned, more of a good thing is extremely welcome as well! I've only played on my own so far, but I've had a ton of fun with the game so far.

I'll discuss possible spoilers in the comments if there is any interest. In particular, I locked a very cool character today although I actually knew earlier that he was in the game. I still haven't locked Jigglypuff. They apparently made her much harder to unlock this time around. (Cue Lemming?)

I just had a particular character join me in the adventure game, so I think I can unlock him now. I'm going to go do that...

Stay tuned...

This is just to let you know that there is some stuff that I am not supposed to blog about. But stay tuned and watch this spot... because eventually I will be allowed to blog about these things.

But don't worry. The world isn't coming to an end or anything.

See you later!

Wednesday, April 02, 2008

Erdos-Schroder numbers?

Courtesy Lemming, here is a fantastic networks comic on XKCD. To fully understand the Erdos-Schroder number deal (at least if you're a Lloydie from a certain era), take a look at the tooltip.

Lego ballparks

Take a look at these sweet pictures of ballparks made out of Lego! That is just awesome.

(And for a blast from the past, you can go here to check out the stories from the bible as told using Lego. The site even includes warnings so that you know which stories it's safe to show to your kids.)

Tales from the ArXiv: Steroids and Power Laws edition

Here is the abstract of a paper that just got posted on the arxiv:

\\
arXiv:0804.0061
Date: Tue, 1 Apr 2008 03:59:08 GMT (41kb)

Title: Statistical evidence consistent with performance-enhancing drugs in
professional baseball
Authors: Alexander Petersen, Woo-Sung Jung, and H. Eugene Stanley
Categories: physics.pop-ph physics.soc-ph
Comments: 9 pages, 4 figures
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
\\
Statistical analysis is a major aspect of baseball, from player averages to
historical benchmarks and records. Much of baseball fanfare is based around
players exceeding the norm, some in a single game and others over a long
career. Career statistics serve as a metric for classifying players and
establishing their historical legacy. However, the concept of records and
benchmarks assumes that that level of competition in baseball is stationary in
time. Here we show that power-law probability density functions, a hallmark of
many complex systems that are driven by competition, govern career longevity in
baseball. We also find universal power laws in the distributions of all major
performance metrics for pitchers and batters. The use of performance-enhancing
drugs has a dark history, emerging as a problem for both amateur and
professional sports. We find statistical evidence of performance enhancement in
the analysis of home runs hit by players in the last 25 years. This is
consistent with the findings of the Mitchell Report [1], a two-year
investigation into the use of illegal steroids in major league baseball, which
revealed that over 5 percent of major league baseball players tested positive
for performance-enhancing drugs in an anonymous 2003 survey.
\\ ( http://arxiv.org/abs/0804.0061 , 41kb)

Tuesday, April 01, 2008

Life on Mars

It's not just for David Bowie anymore, and Google and Virgin can help you realize any dreams you might have of going to Mars.

Or perhaps you'd prefer to send e-mails back in time?

New streetprices.com product

Courtesy Autumn Looijen, you can go here to read about an new, innovative, environmentally-friendly product that streetprices.com announced today.

Tales from the ArXiv: Paradoxical Popup edition

Here's the abstract of a paper that just got posted on the arxiv:

arXiv:0803.4357
Date: Mon, 31 Mar 2008 00:24:19 GMT (733kb)

Title: Paradoxical popups: Why are they hard to catch?
Authors: Michael K. McBeath, Alan M. Nathan, A. Terry Bahill, David G. Baldwin
Categories: physics.pop-ph
Comments: 28 pages, 10 figures, sumitted to American Journal of Physics
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
\\
Even professional baseball players occasionally find it difficult to
gracefully approach seemingly routine pop-ups. This paper describes a set of
towering pop-ups with trajectories that exhibit cusps and loops near the apex.
For a normal fly ball, the horizontal velocity is continuously decreasing due
to drag caused by air resistance. But for pop-ups, the Magnus force (the force
due to the ball spinning in a moving airflow) is larger than the drag force. In
these cases the horizontal velocity decreases in the beginning, like a normal
fly ball, but after the apex, the Magnus force accelerates the horizontal
motion. We refer to this class of pop-ups as paradoxical because they appear to
misinform the typically robust optical control strategies used by fielders and
lead to systematic vacillation in running paths, especially when a trajectory
terminates near the fielder. In short, some of the dancing around when
infielders pursue pop-ups can be well explained as a combination of bizarre
trajectories and misguidance by the normally reliable optical control strategy,
rather than apparent fielder error. Former major league infielders confirm that
our model agrees with their experiences.
\\ ( http://arxiv.org/abs/0803.4357 , 733kb)


Comment: The Magnus force seems to be rearing its ugly head again. It was giving me all sorts of trouble in a research project on vortex lattice locking in rotating Bose-Einstein condensates (the paper has now been accepted, and I'll write a post about it when it appears in print), and I was messing up stuff conceptually that I ought to have known. Then I became doubly embarrassed when I realized that the Magnus effect is essentially exactly why I can put so much spin on ping pong balls (the effect becomes rather significant for light balls like that). I apparently can't escape it...