Saturday, October 9, 2010

The Dark and Evil Forest (My Backyard)

The house (or “terraced” as they call it here) that I rent from the college has a nice little garden in the back. As I mentioned shortly after moving in, I did not have much motivation to take good care of the garden. Then later that year, when I discovered a giant monster spider named Shelob living there, I decided that it was a good idea never to set foot in the garden again.

A year later, as one might expect, the garden began to get a bit overgrown. Actually, it began to get a lot overgrown. It looked like the deepest and darkest part of the Amazon jungle: I keep expecting to see anacondas and jaguars.

Unfortunately, it is written in my lease that I am supposed to keep the garden under control, and the all-knowing powers-that-be at college found out what it looked like and sent me an email reminder
This is just a gentle reminder that we do expect the tenants of College houses to keep the garden of their house under control
(This was actually one of the 363 emails that were lost this summer, so I managed to spend the whole summer thinking I had gotten away with my jungle experiment.)

This is what my garden looked like yesterday:
My excuse – that I’m turning the garden into a forest to combat global warming – might not go very far. So early this morning, I went and got myself some garden shears and a bunch of large garden-waste bags and went to work. My first shock was that most of the huge plants that you see in the picture are actually stinging nettles. Although you can apparently make good food from this stuff, the plants are plenty nasty. Even with thick gloves on they can sting you, and it really hurts! You can get some major welts that last for days. So the weed cutting went very slow as I only very gently approached these evil beasts.

Bit by bit, I filled up waste-bag after waste-bag. No doubt this is going to be a long project. So far, this morning, I pulled weeds for about three hours before I ran into Shelob, the monster spider, who scared me back inside. I decided that I’m not going to do any more gardening until later in the fall when it becomes too cold for spiders.

This is where I left the situation.

I know it doesn’t look all that much better, but maybe it is a start. It is hard to even see that it has improved, but believe it or not, there were four full-sized garbage bags of weeds removed from the yard between the first and second photo. At least there are one or two places where you can actually see the ground in the second photo.

The email black hole

The whole world is far too dependent on email. I am no exception. I have three email accounts that I check many times daily --- and usually I respond fairly quickly, even to things that I could probably ignore with few ill effects. But email is my main connection to most of the world, so I try to keep the lines of communication flowing properly.

This summer, however, something unimaginable happened – my email broke down. (shudder!) I didn’t notice it at first because only a small fraction of my emails were getting lost --- being mistakenly forwarded to a black hole of the cyber-aether. As the term began this fall, increasingly people would say to me “didn’t you get my email?”, and I’d just look puzzled. Finally, this week I figured out that there really was a problem and I started investigating. To my complete horror, I discovered a hidden backlog of 363 emails sent over the last few months. So (after fixing the forwarding problem) I started going through all 363 emails. Perhaps not surprisingly, it turned out that of these 363 emails that I was so horrified to have missed, only 6 turned out to be important enough to actually require a response (and/or an apology for not having responded sooner), and actually even these were not all that crucial. 6 out of 363 --- a pretty small fraction. Considering how much time I spend reading and writing email, I’m starting to wonder if I might not be better off just to send them all down the black hole.
Tuesday, October 5, 2010


The Nobel Prize in Physics today was awarded for the discovery of Graphene, a single layer carbon sheet. Back in this post in 2009, I mentioned that this was a hot topic at the APS march meeting.

It turns out that the whole trick to producing graphene is Scotch-Tape. If you take a piece of tape and you lightly touch it to graphite (pencil lead) you frequently will pull off just a single layer of carbon. Pretty cool. (This trick for pulling off thin layers with tape has been known for many years to chemists and material scientists).

Back in this post when I was taking bets for last year's Nobel prize, I made the following statement suggesting that it was not actually deserving of the prize:

Reuters proposes Geim and Novoselov (22%) for the discovery of graphene (carbon sheets) and Ijima (14%) narrowly behind for the discovery of nanotubes (carbon sheets rolled up into a tube). Not that I am opposed to carbon but…

I will remind everyone that Buckyballs, yet another form of Carbon, already won the Nobel prize recently – but in chemistry, not physics. I will also remind everyone that not every molecule made of carbon deserves an immediate Nobel prize. I know that the Carbonists have been lobbying hard, and admittedly both nanotubes and graphene are pretty cool. But I don’t think they are so overwhelmingly cool that they need a Nobel prize just yet. And if the lessons of Buckyballs are anything to learn from, we should expect that the hype will far outweigh the actual usefulness of, or interest in, the stuff in the long run.

I'm amused to see that Doug, over at nanoscale views seems to have a similar opinion.

On the flip-side, graphene is pretty cool stuff. If any fraction of the hype turns out to be true in 10 years, then I would certainly support the prize (and simultaneously eat my words). But from the buckeyball experience I would have thought the Nobel committee might have waited a bit longer on this one. It isn't like the winners are old geezers about to croak who have to be given the prize now since they are not going to survive until next year.

So there you have it... the Nobel prize won with Scotch-tape.
Sunday, September 26, 2010

Presentation to the Visitor

Last Saturday, Somerville College officially inaugurated its new Principal, Dr. Alice Prochaska. The ceremony is actually known as “Presentation to the Visitor” with “Visitor” here not meaning something out of star trek, but rather meaning the Chancellor of the University – the Lord Patten of Barnes.

[The person with the real power at the top of the administration is actually the Vice-Chancellor. The Chancellor is mainly a figure head, but does preside at formal occasions such as this one.]

During the ceremony of “Presentation,” the Fellows of the College gather, in academic gowns, in the Senior Common Room. Many were dressed in Black and Red, the Somerville colors. (I was happy just to have found a clean shirt and did not think much about the color). Then the senior fellow of the College, Mrs Lesley Brown, presents the principal-elect to the visitor.

[Mrs Lesley Brown has been a distinguished scholar of Ancient Philosophy at Oxford for many many years – having been elected fellow at Somerville College in 1970, and even having chaired the Philosophy department for several years since then. However, having been elected fellow so young, she actually never bothered to obtain her DPhil or PhD, and is thus listed as Mrs rather than Dr or Professor]

Mrs Brown then did the “presentation”, reading the officially prescribed text, in English (Of all the times when Latin might have been appropriate, this might have been one – being that Mrs Brown is a Latin expert).
I, Mrs Lesley Brown, Fellow of Somerville College, in the University of Oxford hereby declare the Dr Alice Prochaska was formally elected Principal of said College, in Succession to Dame Fiona Caldicott at the stated meeting of the Governing Body held on the 17th June 2009.

Then the Principal Elect makes her declaration:
I, Alice Prochaska, hereby declare that I will faithfully perform the duties of my office as Principal of Somerville College, and will observe the Statutes and By-laws of the College in force for the time being

People were a little puzzled by the phrase “for the time being” that occurs in this declaration, but that is what is officially prescribed in our statutes (although no one could quite explain why this phrase is inserted).

And finally the Visitor confirms that this has been witnessed
I, the Right Honourable Lord Patten of Barnes, Chancellor of the University of Oxford, and Visitor of Somerville College in the University of Oxford, hereby declare that Mrs Lesley Brown, Fellow of Somerville College, having announced to me on this twenty-fifth day of September 2010 that Dr Alice Prochaska had been duly elected Principal of Somerville College, presented to me Dr. Prochaska as said Principal. The said Dr Prochaska declared before me that she would faithfully perform the duties of the office of Principal of Somerville College and would observe the Statutes and By-laws of the College in force for the time being.

That first sentence is a bit hard to Parse, huh?

After the ceremony, toasts were made to Somerville and to our new Principal, and we all adjourned to the Margaret Thatcher Centre (the Iron Lady was a Somervillian) for lunch. This gave the fellows a chance to catch up with each other after their respective summers away.

At one point (after only about four champagnes) I found myself sitting next to the Visitor, the Lord Patten. I should have done my research about him in advance so that I could have intelligently argued with his disparaging remarks about the Black-Scholes equation -- although if his remarks were focused entirely on the excesses of the system and rather than on the wisdom of the Nobel prize, we might have agreed entirely.

Incidentally, you can also read the new principal's view on this event on her blog.
Saturday, September 25, 2010

Nobel Bets 2010

It is that time of year again -- the time when the best and the brightest from around the world lose sleep wondering if they are going to get that early morning call from Sweden announcing that they have won the Nobel prize.

Last year I placed my wager on Yakir Aharonov and Michael Berry for geometric phases in physics. This turned out to be a bad bet. From now on I am removing Aharonov from my list of likely candidates. Why? Because I was informed that the 1961 work he is most famous for actually discovered 12 years earlier by Ehrenberg and Siday (Even Wikipedia appears aware of this). The fact that it is called the “Ahanronov-Bohm effect” appears to be a good example of Stigler’s law: The principle that nothing is ever named after its original discoverer. (Stigler’s law itself was discovered by Merton).

Since last year, the prize went to Smith and Boyle and Kao for what many people disparaged as “just engineering” (albeit some pretty amazing engineering). Given that, I think this year the prize might go to something a bit more fundamental. A decent bet would be Sir Michael Berry (without Aharonov).

However, for my money, I think the front-runner is the WMAP experiment (Wilkenson Microwave Anisotropy Probe) which measured the fluctuations of the temperature of the universe – telling us a whole lot about its history. It is a very important experiment. Reuters actually agrees that this one is a pretty good bet. Another really good bet (in my opinion) is the Neutrino Mass experiment from Super-K. I bet on them in 2008 (and lost, as usual).

Another bet on Reuters is Ebbesen for surface plasmons: collective motion of light and electrons together on the surface of metals. While this is nice work, and Ebbesen is a good scientist, I think it is far from a Nobel.

Olaf Smits, in Dublin, mentioned a really interesting possibility. While a bit out of the box for a Nobel Prize in Physics, the fact that last year was a bit out of the box indicates that the Nobel committee is willing to break some rules these days. Olaf’s bet is that the prize will be awarded for the discovery of exo-solar planets. In the star-trek futuristic “this is our moment to discover that we are not alone” kind of way, I think a case could be made that this is worthy.
Sunday, September 12, 2010


A long time ago (in a galaxy far-far away)...

…I had a more musical life. I sang in choirs, played in orchestras, played in multiple jazz bands, classical chamber ensembles, and occasionally appeared in marching bands, handbell choirs, and even the stray pit-orchestras (swearing never-again each time). I called myself a “musical slut” because, more or less, I would play anything anywhere any time (thank you Dereth Phillips, where-ever you are, for coining that delicate phrase). These days, mostly just because I have way too many other things keeping me busy, such devotion to music has faded from my life.

Now, as mentioned in this previous post, all spring I heard many details of Christiane’s woes planning her wedding. One of the many things she worried about was the music for the wedding ceremony – she wanted a full choir in the chapel. When I confessed that, yes, I do read music well, and yes, I did once sing in a real choir, I was quickly drafted for the chapel choir and handed a stack of music to learn. Only then did I realize that the last time I tried to sing seriously was during the Reagan administration. I was unsure if the equipment was still even remotely functional.

To begin with, my voice was never great – it had a weak tone and my singing range was poor. I could never even get close to the top of the tenor notes, and I was really really weak down by the bottom of the bass notes. And this was years ago when I actually worked on my voice to stretch my range. Furthermore, I had a bad tendency to miss pitches. Not that I didn’t realize when this had happened – my ear about these things was pretty good. But I’d land on the wrong pitch and struggle to fix things – ending up either spontaneously changing keys or sounding a bit like a trombone doing a wa-wa as I slid between pitches.

Nonetheless, wanting to contribute to this wedding, I accepted the challenge from Christiane. I was fairly confident that I remembered the main secret to learning music – practice, practice, practice. If you study a piece of music enough, until it was like you had written the whole piece yourself, you can’t go too far wrong. (So I hoped).

First of all, I needed a place to practice: preferably a place where no one else would be listening to me singing --- because I was pretty sure that, at least to start with, I would end up sounding like a walrus in heat. A place to practice was harder to find than I had expected. It would have been great if I could have also found a piano to help me out, but alas, random pianos are pretty hard to find when you are on the road. The best practice room I found as the wedding approached was in my office in the Hamilton Institute. I would show up to work very early in the morning (before all the commuting Hamiltonians showed up) and make a whole lot of gargling and warbling sounds trying to learn my music. Then I did it again late at night after all the Hamiltonians went home.

So I spent many hours singing full volume in my office. It would kind of go like this: I would sing two or three measures; then listen to the relevant measures in a recording of the piece; then say out loud “crap, that’s not right”; read the music again (wishing I remembered my solfege better); then try again; then listen again; then curse again; and so it went on. Unfortunately some of the pieces I was supposed to learn had some tricky harmonies – and it took quite a bit of trying and cursing before I made any progress. To make my life worse, the bass parts frequently went either too high or too low for my voice – and as predicted, walrus noises came out instead.

Unfortunately, during these exercises, I was never quite sure that the Hamilton building was empty. So I’d be mid-walrus-sound and I’d see a Hamiltonian looking into my office with either a curious, or sometimes a rather perturbed look --- a perturbed Hamiltonian, as it were (that’s another physics joke). At that point I would put away my music and start on my usual physics work as if I had no idea where the walrus sounds were coming from.

Anyway, after quite a few days of this (hoping that I would not get kicked out of the building for disturbing the peace) I actually started to feel like I had a pretty decent handle on most of the music, and my vocal range was getting just a bit better – now being almost able to convincingly hit most of the high and low notes. Nonetheless, I was also increasingly hoping that the other bass in the choir (there would be only two on a part) would be a strong singer.

The choir would only have one hour of rehearsal just prior to the wedding ceremony. So on the day of the wedding, dressed in my wedding gear, I showed up early and started warming up my voice before the rehearsal. The choir consisted of 5 genuine friends and relatives of the betrothed, and 5 hired guns to fill out the parts – along with a conductor and organist from Somerville college (the organist is a bit famous around Somerville for being the best organist ever to set foot in the place – so I knew we would be fine in that respect). Within about 30 seconds of singing, I knew that this whole adventure was going to be no problem. The voices in this choir were wonderful --- all I had to do was not completely screw up and everything would be fine. The other bass (a childhood friend of Christiane’s named Martin) was a very solid singer and all I had to do was follow him (Thank you Martin!). I was probably the weakest voice in the choir by a good margin. It was very fun to sing with such a talented group.

So here were the pieces that were part of the service:

The first song at the beginning of the service was a modern hymn or something of the sort. I was a nice tune, although it sounded to me a bit like the kind of song you might hear at a Christian youth-group convention or up-with-people concert. It is in German so I have no idea what it means, but I strongly suspect that the words are in similar spirit to the youth-group-esque “we should all love each other” blah blah blah. This is not the actual arrangement we sang, but it gives the right feel of the kind of harmonies that were used (although it was a piano rather than electric organ accompaniment). To my taste, the best version of this song on the web is this rather simple version from a plain girl with a nice but not particularly spectacular voice just singing and playing guitar. It sounds a lot less like “up with people” this way. Kudos to her whoever she is.

The next musical part of the service was this standard German hymn. I was told that the Germans in the audience would fully expect this one to be sung.

During the bulk of the religious part of the service there were a bunch of little Kyrie-s interjected between the Greek orthodox priest’s singing of various bible verses. This was only a problem because the priest would pick some random pitch out of the air and we were supposed to come in on four part harmony with respect to his random pitch (it worked only about 70% of the time).

The hardest of the pieces came near the end of the service: The Lord Bless You and Keep You -- a very beautiful but difficult tune by the well known (still living) choral composer John Rutter. The harmonies on this one tested even some of the good singers. I really suffered to learn this. The piece also gave the sopranos a nice chance to shine (and indeed some of the sopranos had wonderful voices).

Finally, the majestic conclusion of the service, and my favorite of the pieces by far: “Lord in Thee Have I Trusted”, by George Frideric Handel. This piece, the conclusion of his “Dettingen Te Deum,” is a magnificent work meant as a celebration of a military victory as much as in praise of God. Considering the level of organization that went into putting together the wedding ceremony, the spirit of military victory seemed appropriate.

The piece begins with an alto solo which was to be sung by our common friend Sabine Müller (lecturer in modern languages). I’ve known for a while that Sabine took singing lessons, but for some reason it never really occurred to me that she might actually have a great voice (oh me of little faith). During rehearsal when we launched into this work and I heard her sing this solo for the first time I admit I was rather shocked by how good she sounded. Then when the rest of the choir came in with the strong sopranos, 5 part harmony, and organ accompaniment, the whole thing knocked my socks off.

So in the end my experience singing for this wedding went really well (meaning, it didn't sound like a walrus). It was fun contributing to the event and I realize I have missed the feeling of being part of a musical ensemble. Maybe I’m even so inspired that I’ll join a choir. Then again, joining choirs in Oxford can be bad for your health, as the famous Inspector Morse once discovered.
I received this plot from my brother Rob.

I think there needs to be less green.
Saturday, September 11, 2010


Whenever I visit the National Irish University at Maynooth (which I have been doing quite a lot recently) I am loaned an office in the Hamilton Mathematics Institute, not to be confused with this Hamilton Mathematics Institute, only a 45 minute train ride away. Both of these institutes are named after Ireland’s most famous mathematician and physicist, William Rowan Hamilton. If you have an office in one of these institutes you can call yourself a Hamiltonian.

And if you take the train into work in the morning then, because of you, all the other Neanderthals on the train will never evolve --- because they commute with a Hamiltonian.

If you did not get that joke, you are not a physicist.
Friday, September 10, 2010

I'm not making this up....

... flying into Stockholm the girl sitting next to me had a dragon tatoo. On her ankle though. I tried not to make her angry.
Thursday, September 9, 2010

Tying the knots

No, not another talk about the mathematical theory of knots. Here I’m talking about the other knot – you know the one I appear to be allergic to – marriage.

A fair number of people get married right out of high school. More get married just after college. Then some more a few years after college. In my late 20’s and early 30’s, I must have gone to half a dozen weddings per year. My one nice suit got a lot of action. But by my late 30’s pretty much all my friends were either already married or, like me, didn’t appear to be the marrying type. Between 2005 and 2009, I’m not sure if I went to even a single wedding (er.. ok I think one in 2006, Ren?). Most days I can’t even remember what color my nice suit is, or where I put it for that matter.

Then in the year 2010, long after the wedding rush appeared to be completely over, all of a sudden 4 wedding invitations appears on my desk simultaneously! Here’s the list of the people to whom congratulations are due:

Carobe Hart and Nick Read:

Nick is a friend and colleague (a professor at Yale) who I have known for many years (He is also one of the few people around who I consider to be much much smarter than me – most people are only much smarter, but not much much smarter). Unfortunately, their wedding was scheduled right in the middle of the teaching term this last spring and it was humanly impossible to make it to the wedding and still fulfill my teaching responsibilities. I’ll make it up to them somehow.

Terrie Cooney and Rob Grainger:

Terrie is a good friend from back in New York, but as luck would have it, we both ended up in the UK (she’s in London). I met Terrie playing Frisbee very shortly after I moved down to New York in 1997 or so. We had a terrific little group of people who would get together every Sunday to play. Over the years we complained to each other an awful lot about being single. I really would have loved to have been at her wedding this summer. I’ll have to make it up to them as well! But unfortunately their wedding was scheduled at essentially the exact same time as …

Sarah Israelit and Nathan Roe:

Sarah is a friend of mine, originally from college, but we only became close many years later. I felt deeply invested in this wedding because a few years earlier when she had just started dating Nathan, I got almost daily panicked emails about “He doesn’t like me enough! I need to have a talk with him! I’m not sure this is working out” … and I sent many many an email back saying “Chill out. This is going great. He’s totally into you. Just relax.” (As if I really had a clue.) It was a great vicarious victory that it all worked out. I attended the beautiful wedding this July in Portland Oregon.

Christiane Riedinger and Luke Kontogiannis:

Christiane is the first new friend I made after moving to the UK. (“friend” is defined as a person who you can call and say “lets go get ice cream” at any random time). Through Christiane I met Luke, and a bunch of other nice folks too. (Pictures of them and their posse are here). This was another wedding that I felt very very invested in. Since I hang out with them very frequently, I heard an awful lot about the trials and tribulations of planning a wedding this year (actually they planned three weddings: one in Germany, one in Greece, and the big one in Oxford). The logistics of all this sounded to me to be more complicated than planning the invasion of Normandy. Last weekend they finally had the last of the three weddings in Oxford, and amazingly, everything (even the weather) was beautiful and it all went with not a single glitch. Another great victory! The bad news is that the two of them are moving to Cambridge in only a few weeks. Maybe they won’t like it and they will decide to move back. We do have better ice cream I’m sure.
Monday, August 23, 2010

Who Killed Hugo?

A few weeks back, I lamented the death of my pet spider, Hugo, and I wondered what might have killed him. One of my thoughts was that he met another spider who was just a bit bigger and nastier than he was, and they had a bit of a spider-rumble. But Hugo was a pretty big guy, and I couldn’t imagine any spider hanging out in my house who was all that much bigger than Hugo.

Then I went away to the states for a few weeks. Upon my return I discovered that, not only was there a ginormous humungo Godzilla-spider hanging out in my bathtub, but he was acting like he owned the place!

I think I found Hugo’s killer!

I eyed him accusingly but he just snarled back. Well, this bathroom was not big enough for the both of us. So I left. I mean this guy was really big! Upon throwing a ruler near him I determined that his wing-span broke 6.5 inches. I did try to photograph him (with a telephoto from half a mile away. I didn’t want to get anywhere near this thing). I apologize that the photo is so bad that it is hard to see how damn large this thing was. But believe me, he could have eaten a large rodent.

I knew that I had to find a way to eliminate this demon-spawn. I thought about an exorcism, but not being religious – yet still being frightened to death when I watched the exorcist, I decided that this was not the right approach.

I armed myself with some serious heavy ammunition – all the shoes I owned. I stood out in the hallway, a good distance from the beast, and catapulted the shoes in his direction. After the first shell landed right next to him, he knew he was under attack. He scampered to the other side of the bathtub. Ha! Unfortunately he still had a spider-sized brain, and he did not realize that the other side of the bathtub was much easier for me to hit. With the second shell (my old hiking book) I fired and squashed him flat. I waited for a few minutes to see if he was planning on throwing the boot back at me. But after a few more minutes I determined that he really was deceased.

So it was that I avenged the death of Hugo.

Right now I am off in Ireland for a few more weeks. I'm wondering what new monster is going to be living in my house when I get back.
Saturday, August 21, 2010

The Girl Who Played with… Euclid’s perfect theorem:

Like most of the northern hemisphere, I’m in the middle of reading Stieg Larsson’s books “The Girl with the Dragon Tatoo” series. In the second volume, (“The Girl who Played with Fire”) our heroine, the punked out antisocial hacker, Lisbeth Salander, gets absorbed in recreational mathematics.

Now, in almost any popular novel, when the author starts delving into math, I am usually pretty familiar with whatever theorem, or unproven conjecture the author is mentioning -- frequently much more so than the author. I applaud the attempt to bring more science into popular fiction, but I don’t usually learn much from it.

However, on page 21 of the “The Girl who Played with Fire” the author mentions an ancient – and very beautiful! – theorem by Euclid, which rather shockingly I had never seen before. (A major gap in my education!) I scratched my head for a moment, then figured out Euclid’s proof (despite the fact that Lisbeth Salander sort of gets it wrong).

First of all: Here is the statement in the novel:

She was fascinated by Euclid’s discovery in about 300 B. C. that a perfect number is always a multiple of two numbers, in which one number is a power of 2 and the second consists of the different the difference between the next power of 2 and 1. This was a refinement of Pythagoras’ equation and she could see the endless combinations

6 = 2^1 ( 2^2 -1)

28 = 2^2 \times ( 2^3-1)

496 = 2^4 \times( 2^5-1)

8128 = 2^6 \times ( 2^7 -1)

She could go on indefinitely without finding any numbers that would break the rule.

(Yes, Larsson likes to write in Italics). OK, now the proper statement of the theorem.

Definition: A perfect number is a number where the sum of the number's factors adds up to the number itself. For example:

The factors of 6 are 1, 2 and 3. 1+2+3 = 6 so 6 is a perfect number.
The factors of 28 are 1,2,4,7,14. 1+2+4+7+14=28 so 28 is a perfect number
and so forth.

Euclid’s theorem: IF (2^k-1) is a prime number THEN 2^{k-1}\times (2^k-1) is a perfect number.

Salander does not mention the IF required of this theorem, but note that on her list of perfect numbers, she lists k=2,3,5,7 which are cases where (2^k-1) is prime. This type of prime is known as a Mersenne Prime]. How Euclid proved this theorem is beyond me. He was brilliant, but he did everything with geometry – and very little algebra (which is how I intend to prove it).

Almost 2000 years after Euclid’s proof, Euler proved that if an even number is perfect, then it is the form given by Euclid’s theorem. It is still not known if any odd perfect numbers exist --- although if they do exist they have to be ginormous since it has been proven that no odd perfect numbers exist less than 10^{300} . Assuming there are no odd perfect numbers, then there is exactly one perfect number for each Mersenne prime. It is not known how many of these there are.

OK, a quick proof of Euclid’s theorem: Consider the number 2^{k-1} (2^k-1) . If p = (2^k-1) is prime, then the only factors of (2^{k-1})p are

1,2,4, \ldots, 2^{k-1}


p,2p,4p, \ldots, 2^{k-2}p .

Now the sum of the series

1 + 2 + 4 +\ldots, + 2^{k-1} = 2^k -1

And similarly

p + 2p + 4 p + \ldots + 2^{k-2}p = p ( 1 + 2 + 4 + \ldots 2^{k-2}) = p(2^{k-1} -1)

So the sum of all the factors of the number gives

(2^k-1) + p(2^{k-1}-1) = (2^k-1) + (2^k-1)(2^{k-1}-1) = 2^k(2^{k-1}-1)

which is the number itself!
Thursday, August 12, 2010

Harvard is Easy – Almost

This year’s hiking/camping trip with Carissa and Lin was to Mount Harvard –- the third highest peak in Colorado at 14,420 feet (4,395 meters to those who insist on Système-International d'Unités). It is the fourth highest peak in the 48 states behind California’s Mount Whitney, and Colorado’s Mount Elbert and Mount Massive.

You can read about last year’s Hiking trip on this page and this page (I apologize that the pictures are now defunct). Given that we failed to reach a summit last year, we decided on a simpler climb this year. Harvard is listed on the web as a clearly marked trail with little, if any, scree to slog through, making it a high, but relatively easy climb.

Our intent was to hike a few miles into the park on Friday and set up camp in between Mount Harvard, Mount Yale, and Mount Columbia of the Collegiate Range of the Sawatch. Then on Saturday we would climb Harvard, and on Sunday we would do the slightly smaller Columbia, and also walk back out to the trailhead by nightfall.

As planned, our hike started on Friday with full packs. We walked a few miles up the trail (gently uphill) until roughly the place where the trail splits towards either Harvard or Columbia. We set up camp near the fork in the road. The campsite we found had clearly been used by many before – it was perhaps the softest and flattest dirt I’ve ever seen anywhere in any woods. Add to this a standard thermarest air mattress and a thick sleeping bag, and quite frankly my tent was better than the beds I suffer through in many a hotel. I had no complaints whatsoever about comfort.

This was the view from our campsite. For a while we thought that the mountain in this picture is Mount Harvard, but it isn’t. I think it is known as Birthday Peak.

Carissa and Lin were dead-set on not eating freeze-dried camping food this year. So the first night’s dinner was curry-cous-cous with tofu and raisins and cashews and some broccoli soup. It was terrific. We had enough left-over cous-cous for about two days worth of breakfast and then some. After dinner we dove into our respective tents to try to escape the evening feeding frenzy of mosquitoes.

Another observation about Colorado mosquitoes: Last year I noted that the Colorado breed of mosquitoes are a lot slower and dumber than the east coast variety. This year I will add the observation, that if they do manage to bite you, it itches far far less than in New Jersey. What sin did New Jersey commit in a past life to deserve fast, vicious, and itchy mosquitoes? Maybe they are a product of toxic waste --- sort of like Godzilla being created by nuclear waste.

Now back to hiking:

When hiking in Colorado, one should really be on the way down from the mountain by noon since thunderstorms tend to come in the afternoon and it is rather dangerous to be caught up high during a storm. Even given this restriction, it is actually possible to climb both up and down Harvard and then up and down Columbia all in one day, but only if you start insanely early in the morning. During the night we heard a few climbing parties slogging by in the wee hours of the morning, and we assumed this was their intent. We, on the other hand, slept luxuriously late, ate our cous-cous breakfast, drank some coffee, and started up the trail at around 7.

Having started the morning a fair distance up the trail already (and with no intent to do two mountains in one day) we did not feel pressed for time. As long as we kept slogging along at a slow pace, we felt we would make the summit easily by noon.

For several miles, the trail was an easy (albeit uphill) country walk. It was well marked and easy to follow and the terrain was about as smooth and clear as you could ask for. For this, we must thank all those people who don’t understand statistics very well. You see, upkeep of many trails in Colorado is paid for by the vast proceeds of the Colorado lottery. It makes me almost want to buy a ticket even though I do understand statistics more or less. In fact one of the topics of conversation on our hike was Baysian reasoning. (But don’t get the idea it was all intellectual conversation --- we had long discussions of which muppet videos were the best).

The smooth trail goes up the left of the picture above. Bear lake is on the right (Despite the name, we didn’t see any bears – but we were careful to hang all our food in bear bags nonetheless). In the background is Mount Yale. Just behind Bear lake is the little peak which we could see from our campsite (possibly Birthday peak).

A bit higher up, the trail became much more steep. But for most of the way (again thanking the lottery) it was an extremely good trail --- like walking up a very long flight of stairs. Of course, once we got above about 12,000 feet, we found ourselves huffing and puffing quite a bit due to the thin air --- about 40% less oxygen than at sea level. Step-breathe-step-breathe, we made progress slowly but surely. Aside from all the huffing and puffing, the climb was not really all that difficult for most of the way.

Along the way we saw a bunch of random cute animals, including Pikas and Marmots which are both fundamentally rats, but are also insanely cute. That's a pika above and a marmot below (the fat one). I still expect him to start singing "I'm all right... don't have to worry 'bout me".

Near the very top, the trail suddenly turned into a boulder field and finally stopped being so wonderful. In Colorado, hiking trails are ranked into “classes” describing how technical they are (See here for a description). Harvard is supposed to be a class-II climb, meaning that you rarely need to use your hands. However, over this boulder field (with some pretty exposed cliffs staring you in the face) it is probably class-III. Here's a picture of me a bit before the boulders really start getting serious.

Fortunately, the boulder field is quite short and we reached the summit with no real trouble – and well before noon. Here’s a picture of the three of us on the summit (Carissa is in front, Lin in the middle, and I’m hiding in back).

Some guy was on top smoking a cigarette and taking pictures with his iPhone --- and get this: he actually had reception on the top, so he was sending pictures as email. This photo was taken by his iPhone and sent directly to my Mom. Actually it is not such a bad picture. The picture would have been better if he could have backed up a few more feet to get more of a view, but then he would have fallen off a five hundred foot cliff.

In this final summit photo, I’m pointing to what I think is Mount Oxford. We had discussed climbing Oxford as well, but decided against because the trail is not supposed to be well marked – maybe I’ll try it next year. Actually it turns out that Oxford is the mountain further to the right in the photo (over my left shoulder). The mountain I’m pointing to is probably Mount Belford.

After a peanut butter lunch on top (jealously protecting our food from an eager Marmot), we started the long climb back down. From the top, the weather still looked clear so we had plenty of time to go slow downwards. (I climb down extremely slowly – Carissa and particularly Lin seem to have the genes of mountain goats and were able to go down at a much greater speed).

Despite my slower progress I nonetheless managed to twist my ankle on the way down. Crunch. Ugh. Fortunately it didn’t seem too bad and although it hurt a bit, it was no problem to keep walking on it.

As we got closer to the bottom, and the weather had still not turned foul, we felt free to linger even longer as we went along. Back down in the country fields we even took our time and sat by a nice creek for a while soaking our feet. At this point we had only about two relatively flat miles back to our campsite. Here I pose for a picture near the creek. Harvard is in the background.

Just as we were leaving the creek to head back to camp I commented “You know, Harvard was pretty easy!”. Well, unfortunately, it seems the mountain gods heard me. About a dozen steps after that my twisted ankle started making an unpleasant (and painful) crunching sound. Fortunately, Lin was carrying an Ace bandage which patched things up temporarily and I had little trouble getting back home. That will teach me not to insult the mountain gods.

So Harvard was easy, almost.

Back at camp, we started cooking dinner. This time it was mac-and-cheese with (dehydrated) tuna. Again yum. Although bringing real food is a bit more heavy than bringing all dehydrated hiking food, I’d vote that it is totally worth it.

While we had planned to climb Columbia the next day, considering the condition of my foot, this was not going to happen (at least for me). I was hoping that at the very least the ankle wouldn’t swell up too much, and I’d be able to hike out of the woods without too much problem the next day (being carried out would be rather humiliating). Carissa and Lin graciously decided that they would not climb Columbia without me (Actually it looked like a bit of a scree-fest anyway – the grapes were sour).

The next morning my foot was no better, but no worse either. So at least I would be able to walk out of the woods. We slept late, cooked breakfast (oatmeal), packed our tents and had a relatively easy hike back to the cars. Had a few beers by a river to celebrate our successful trip, and called it a day.
Tuesday, August 10, 2010

The Best Physics Lecture Ever

Out in Aspen Colorado, a few times each summer, there are physics lectures aimed at the general public, given in the memory of Heinz Pagels. Many years ago I heard one such lecture on the subject quantum mechanics given by a friend of mine named Shankar (one name only) who is a professor at Yale. The lecture was both entertaining and inspiring and accessible to all (not just to the physics cognoscenti). I remember how impressed I was, and I thought how great it would be to be able to give such a performance.

Last year I was honored to be asked to give one of these Pagels lectures. I spent literally weeks preparing it, trying to live up to the high standard set by Shankar. The lecture went very well, and maybe I got close to his level, but still I have to give credit where it is due: his lectures are still the yardstick by which other physics lectures should be measured. Perhaps we should declare a lecture to be a milli-Shankar if it is one one-thousandth as good as one of Shankar’s lectures.

This summer, Shankar gave yet another lecture --- this time on the subject of relativity – one of the most beautiful subjects in physics. This lecture was even better than his previous one. In fact, it was perhaps the best physics lecture, on any subject, that I have ever heard!

Fortunately, you can find all of these lectures streaming on the web. While sometimes a bit is lost in the translation to low-quality streaming video, nonetheless, I think they are all worth watching.

Here is Shankar’s lecture on relativity.

Here is his lecture on quantum mechanics.

... and in case you missed it last year, here is my lecture

Bobba Hannah Sandusky

My Great-Great-Grandmother, Hannah Sandusky, was a rather unusual woman. Having immigrated to Pittsburgh around 1860, she became known as “The Angel” to those she helped. To everyone else, she was known as “Bobba Hannah.” “Bobba”, or “Bubbe” is Yiddish for grandmother. It also means “Midwife”, which was her profession -– although she never accepted fees for her services. Over her lifetime she delivered many thousands of babies for the poor in the Pittsburgh area. Although she was horrible at keeping records, she managed to register over 3500 deliveries – and probably far more remained undocumented. Hannah also spent a lot of time doing other charity work, as well as the duties expected of Jewish grandmothers, such as matchmaking.

Thanks to some major legwork by several of my cousins (Kudos to Miriam Baker in particular) this last weekend in Pittsburgh we had the first ever reunion of the descendents of Bobba Hannah. Hannah and Louis Sandusky had eight children: three boys and five girls. Only four of the daughters had offspring, so the Sandusky name died out, and the clan became divided into Raphaels, Gordons, Schugars, and Simons. The clan is now spread out around the world, and until this last weekend, I had only met a tiny fraction of my extended family.

During this weekend I heard a number of interesting stories. There was the story of the funeral crashing cousin who ended up being locked in a closet by the undertaker; and there were many stories of my grandfather, who was frequently on the wrong side of the law but managed to always evade the feds one way or the other. But perhaps the most interesting story was how my grandmother met my grandfather.

In 1913, shortly after immigrating to Pittsburgh from Lithuania via South Africa, Eva Grabowski was told that an unusual event would be taking place: a funeral procession which was made up of both Jews and African Americans. Needless to say, this was Bobba Hannah’s funeral.

Here I quote from a transcript dictated by my grandmother a few years before she passed away:

I was standing on the verandah watching the funeral procession... On the other side of the road a young man was also standing on a balcony watching the procession where he spotted me. We became acquainted and his name was Ike Simon. He was a big man with a heart of gold and when he asked me to marry him I decided to accept, having in mind, if it didn’t work out, I would leave him and return to South Africa.

Well, it did work out, and I’m sure Bobba Hanna, the part-time matchmaker, would have been very pleased.

[Note: There is some confusion in the story as to whether they met at Hannah's funeral or some other funeral. It makes a better story this way].
Wednesday, July 7, 2010

Some Skunk Funk

… that is the title of a famous Brecker Brothers Jazz tune. (See here for a great performance). Unfortunately, it is also what I discovered when I opened my suitcase after its damp contents had been fermenting for a week. (See here for the long story).

Nonetheless, I’m very happy to have the suitcase back. For a while I was sure that I would never see my snoopy T-shirt or my hiking boots again. A huge thanks to the nice people at the Benasque physics center for hunting down the suitcase. And also a huge thanks to Adam Nahum who hand-carried the suitcase back from Benasque to Oxford.

I've washed the stinkin jeans several times now and they are still a bit skunky and a bit funky... but they are recovering slowly.
Saturday, July 3, 2010

The Short Life of Hugo the Spider

A few weeks back, I returned home to my Oxford abode, walked into the bathroom and discovered an enormous spider sitting in the middle of the floor looking hungrily at me. Now, as I've mentioned before on this blog, I'm not really much of a fan of spiders. I immediately decided that the house was not big enough for the both of us and I went to get my trusty spider-destruction-device: My hiking boot.

As I planned my attack, I noticed that this spider was clearly a different breed from the enormous Shelob that I encountered last summer. Shelob was a brown and slightly hairy, totally ginormous, orb-weaving (and probably physicist eating), creature. The current spider (who unlike Shelob, was already inside my house), was a large black (and probably physicist eating) spider, who did not appear to have a web. This probably meant he was a hunting spider -- which meant he was fast and probably had good eyesight. So I snuck up on him slowly, and brought down the hiking boot with a very swift blow.

Unfortunately, the spider was quick --- quicker that the boot. It jumped out of the way, scampered to a corner of the bathroom and hid in a little hole (a spider-hole, as it were) where I could not get it. He won this round, but certainly there would be others.

The next day, when I came home from work, I was again greeted by the spider in the middle of the bathroom floor. Now, despite the fact that a spider's brain consists of only two ganglia, it had clearly learned that I was a threat. As soon as it saw me, it scampered off to its spider hole again. This behavior repeated itself almost every day for a week. I would return home, and as soon as it saw me it would run away. Never did I have any chance to splat him with my boot. Eventually, I conceded that I would be sharing my apartment with a huge black spider. He could have the bathroom during the day, but when I came home at night, he had to go back to his spider hole. Being that I was resigned to having a roommate, I figured he should have a name: Hugo.

I returned home from work every day and I would yell "Hugo, I'm home" (Hoping this would prompt him to pre-emptively evacuate). Sometimes when I was showering I would see him try to sneak out of his hole, and I'd talk to him. "OK, Hugo... you can look around a bit now, but when I get out of the shower, you better be gone again"... and usually he was. After a few weeks of this, he didn't seem quite so scary any more. He was clearly pretty frightened of me, and I started to feel bad about making his life so difficult.

So bit by bit, Hugo went from a physicist-eating monster to a harmless pet. He didn't seem to have any plans of murdering me in my sleep, so I stopped making a point of chasing him back to his hole. Not that I became a big fan of spiders overnight, but maybe Hugo was OK. At least he had personality.

Then one day I came home from work and Hugo was sitting in the middle of the bathroom floor as he often was... but this time he was half-upside-down and seemed to be having convulsions. Clearly he was a very sick eight-legged animal. I don't know much about spider-health so I just talked to him and encouraged him to recover. I figured the best thing I could do was probably just to let him try to recover on his own.

Sadly, the next morning, Hugo was stone cold. Somehow I felt a small twinge of sadness for Hugo. He was an exceptional spider --- if for no other reason because he managed to slowly make me not afraid of him. I still don't know what killed him. Two possibilities come to mind:

(1) Hugo could be (and probably was) Hug-ette. Some species of spiders die shortly after laying eggs. Possibly this was simply Hugo's time to go. (And possibly I will be meeting Hugo Junior in the near future).


(2) Some other spider (or other insect) had taken Hugo in battle. While this may sound unlikely, given Hugo's unusual size, a few days later I spotted a much smaller, but very very quick looking spider who could possibly have done the job. I went after him with my hiking boot -- but I missed.
Wednesday, June 30, 2010

The Retirement of Dame Fiona: The Spell is Broken

Over the last few weeks, there have been many goodbyes for Dame Fiona Caldicott who has been Principal of Somerville College for fourteen years and is retiring this summer. There have been numerous formal dinners, lunches, and so forth to see her off and to celebrate the years of her good leadership (At one I such event I even wore my first real bow tie – the kind you actually have to tie instead of clipping on – which only took me about an hour to figure out).

Now, Fiona is not one for giving long speeches, or listening to long speeches for that matter, but these things are hard to avoid when coming to the end of an era. Of these speeches given at these formal events, probably the best one was given by the JCR president (Junior Common Room – meaning undergraduate student body). It was in some ways long and rambling and it even had some cringe-worthy moments. However, it was also very heartfelt – and he was brave enough to say what everyone around the college had been thinking for the last few weeks: The spell is broken.

If you have been reading my blog over the last year, you will already know that the most important icon of Somerville College has for years been Pogo the cat. While Pogo nominally belongs to Dame Fiona, mysteriously no one would ever see the two of them together at the same time. This led to a common belief that Pogo is actually Fiona’s alter-ego --- and the reason that Fiona seemed so well informed about what was going on in every corner of the college was because she wandered the grounds, undetected, in the form of her cat.

But over the last few weeks, on numerous occasions people actually saw Pogo and Fiona together. I even saw it myself. Hushed whispers spread quickly around the college: The spell is broken.

You see, as Fiona bids farewell to the college, her need for such strong magic is no longer, so she and Pogo can now go into retirement at their regular home as a regular person and a regular cat.
Tuesday, June 29, 2010

My Stinkin’ Jeans: More Travel Troubles.

After returning from hiking in Benasque I tried to clean off my muddy and soaked boots, jeans , socks, and shirt, and I hung them to dry overnight. Unfortunately, overnight was not nearly long enough for them to dry, so when I packed up to leave Benasque the next morning I wrapped the whole mess inside of my jeans, and stuffed the damp package in my suitcase. Hopefully the wet and somewhat stinky mess would not be able to infect the rest of my luggage too much during the 12 hour trip. I’d certainly have to wash everything again when I got to Ireland, but hopefully it wouldn’t be too nasty.

I then put my luggage on the bus from Benasque to Barbastro. The bus to Barbastro is a local bus, stopping at every other street corner for the two hour trip down the mountain. Each time the bus stopped, it opened its luggage hold, people got on and off the bus and put luggage on and off. When I got to Barbastro, unfortunately, my luggage was missing --- lost or stolen. I tried to communicate the situation to the bus staff, but being that my vocabulary in Spanish consists of only “hamburgesa” and “cerveza” I was not very successful. The bus to Barcelona left only a few minutes later and I knew that if I waited for the next one, I would miss my flight. So I jumped on the bus and started making a mental inventory of what was lost and what I still had with me.

What I still had with me:

Red t-shirt with an hbar on the front of it
Teva sandles
One fleece

Laptop case
Laptop and Charger
Wallet (including several credit cards, and some euros)
Prescription Sunglasses
One Pen
One novel, unopened.

What was lost:
One new suitcase (Delsey was recently replaced)
One pair of wet and muddy Vasque hiking boots
Some jeans (one pair now wet and muddy)
Two nice shirts and a sweater from banana republic
A bunch of cruddy shirts
One snoopy tee-shirt (“borrowed” from my ex girlfriend)
One flying-spaghetti-monster tee-shirt
A bunch of mostly cruddy tee-shirts (one muddy)
Shorts (old)
One tweed jacket (old)
One pair of “Grinch who stole Christmas” boxers
Nine other pairs of nondescript boxers
One travel iron
One travel alarm
Razors, toothbrush, etc.

Looking at the list, the most valuable thing lost was probably the hiking boots and the suitcase itself (and the emotional value of snoopy, FSM, and the Grinch). If the luggage was actually stolen, I think the thief would be a sorely disappointed with his haul.

Late that evening I arrived in Ireland, and the next morning I stopped at the cut-rate department store and got myself some replacement shirts, boxers, toothbrush, etc. 2 euro for a t-shirt. Maybe I’ll buy a few more of them!

I tried to write to the Bus company in Spain, but I did not hear back from them (again, my limited knowledge of Spanish was probably a bit of a detriment, but with Google translate, I’m pretty sure I can make myself understood). I also wrote to the staff of the physics center in Benasque to see if they could help me. No progress yet.

I don’t know if my luggage will be recovered or not. Each hour it is gone, however, I imagine my wet and muddy hiking gear is fermenting just a bit more. Perhaps after a few more days of nasty growth, the damp jean and boots will be able to walk home by themselves. Or maybe they will be classified as a biological weapon and will be put on the no-fly list.

Update Monday Night: I just got an email from the Benasque staff saying that the bus company thinks they found my luggage! Yay!

Update Tuesday Morning: They discovered that the luggage is not actually mine. Boo!

Further updates will be posted as the story progresses.

Update Tuesday Afternoon: Reversal of fortune #2 : They think they have my luggage again. Yay!
Monday, June 28, 2010

A Busy Day at the Refugio

High up in the Pyrenees, a six hour (sometimes terrifying) bus ride from Barcelona, there is a little ski-resort town called Benasque. Some genius named Pedro Pasquale had a brilliant idea of putting a physics center in this little town. In the language of physics, this center is in the same “universality class” as the Aspen center for physics where I will be again later this summer.

The Pyrenees are quite beautiful, and at least for the week I was there, the weather was mostly beautiful too. The Spanish locals are very friendly and have an enlightened view of life --- which includes a lot of partying and only mild work. The only negative thing I can say about the place is that the vegetarians amongst us seemed to be having a hard time finding much to eat (although the goat cheese was delicious). I, on the other hand, broke my recent vow to eat less red meat and enthusiastically gobbled down chorizo.

After giving a bunch of lectures at the INSTANS (Interdisciplinary Statistical and Field Theory Approaches to Nanophysics and Low Dimensional Systems) summer school early in the week, I relaxed for the latter half of the week, watched a lot of the world cup with the locals (and other enthusiastic Europeans), made much of my very limited Spanish vocabulary (which includes only the words “hamburgesa” and “cerveza”) and took the opportunity to go hiking a few times.

On Saturday, with no classes scheduled, a large group of students and postdocs (plus me) decided to take a long hike. (Some of these students were apparently out dancing at a disco bar until 5am the previous night, and still woke up at 9am to go hiking! Needless to say, dancing til 5am was out of the question for me). The intent was a 10+ hour hike starting in town and going up to almost a local high point (about 1500 meters of elevation gain, I think).

The mountains near Benasque do not look like the Rockies, or the Alps, rather they look like New Zealand. I’ve never been to New Zealand, but I’ve watched Lord of the Rings a bunch of times – and except for Sauron’s watchful eye and the absence of hobbits – the Pyranees look like middle earth.

On the way out of town we had to walk through a herd of rather loud, but not unfriendly, cows. These cows were not mooing, or even lowing, but they were positively bellowing. I’m not exactly sure what they were saying, but perhaps they meant to say “you idiots, can’t you see it is going to rain”. At the time the weather looked great, but…

After about three hours of hiking (and not *too* much elevation gain) we came to the “Refugio” - a tiny shelter by a clear mountain lake at a fork in the trail - where we stopped to eat our lunch. There were a fair number of hikers on the trail, and many of them had stopped in the same place. After a bit of planning, we divided into groups who intended slightly different hikes from there and set off for the hard part of the day. I ended up in the middle-speed group (which was fine with me, being too many years older than the next oldest hiker that day). After only another half-hour of hiking we made it to another mountain lake, and looking ahead, we saw the advanced party of faster hikers on the other side of the lake just starting the hard slog up the steep part of the mountain. Unfortunately, we also saw some ugly looking clouds coming in over the mountain. There was a bit of debate, but rather quickly we made the decision to turn back and try to get back down to the Refugio before getting completely pummeled by the storm.

Within only a few minutes the rain started. Then the rain turned to hail. Then the hail was accompanied by thunder and lightning. Then it just turned back into drenching rain. The trip down was probably almost as slow as the trip up because the rock had gotten slippery in places. By the time we made it back to the Refugio, we were all pretty much soaked to the bone. But alas, the Refugio (which was really tiny – maybe 8 feet on a side) was completely packed with other people who had gotten there first – 16 people in fact. So, a few of us were left out in the rain (I was given an umbrella to help me wait out the storm).

The rain continued far longer than I expected. After about another 20 minutes or so, the advance-group made it down to the Refugio and just decided to keep walking down. Being completely soaked already, and hoping to be able to walk on less slippery surface, I stayed up at the Refugio with the others waiting for it to let up.

An hour later, the sky finally cleared. Fortunately, it was not too cold out, so, although I was very very wet, I was not too uncomfortable (except for numb-ish hands). So we started the long wet slog home. On the hike down, we saw the cows again – who just looked at us and mooed happily “we told you so”.

PS: I saw a Great Pyrenees in the Pyrenees. It made my day.
Saturday, June 12, 2010

Porcelain Heaven

(This is not a joke about a toilet.)

The town of Meissen, outside of Dresden, has been the porcelain capital of Europe since 1710 when porcelain technology was discovered for the first time outside of China.

The historic town itself (founded in 1150) still has palaces, cathedrals, fortresses, and so forth. It was somehow completely spared during the second world war, but it was almost destroyed by neglect during the DDR era (“The government that creates ruins without weapons”). It is worth the visit if you happen to be in the area.

Despite the long history of the town, its greatest fame is its porcelain. About half the physicists attending QHSYST-2010 in Dresden last week made an excursion to tour the town and the famous porcelain factory. I think the tour guides were a bit taken aback that we physicists were there taking detailed notes (or at least I was taking notes) about the details of the porcelain process (being that most physicists don’t really care so much about dinner settings and the like).

So here is the rough process: Feldspar, Quartz, Kaolin, makes the base clay-like material. Underglaze dyes are mainly Cobalt Blue and Chrome Oxide. There are three bakings, 950 degrees C, 1100-1150 degrees C, 950 degrees C. The overglaze painting is after the middle bake. One obtains a 16% reduction in size after the hot baking. While the tour guide was very nice (a third generation porcelain-ite) very quickly we reached questions that the she could not answer and probably had never been asked before. I hope we (I) did not annoy her too much.

The porcelain products are all hand decorated – and hand crafted (if you allow molds within the definition of “hand crafted”). This makes them rather expensive. For example, this 200 piece dinner service (without the glassware or silver) will set you back 30,000 euro (36,000$) more or less.

A hand painted porcelain chandelier was 80,000 euro. Fortunately, the chandelier is hideously ugly and no one in their right mind should want one even if it were free. In fact, this is more or less my opinion of most of their products. Impressive art work, perhaps, but truly awful.

Now, you might think that my distaste for porcelain is just because I am an uncultured nerd... but in fact, I’m not the only one who thinks this. The famous german author Goethe, visited Meissen in 1813 and thought more or less the same. The following quote was translated for me by a nice tour guide:

“It is funny and almost incredible that there is nothing that you would want to have in your household. This is the oddest exhibition of everything that does not please and can never please again”

I fear the tour guide gave me this quote (without a hint of irony) thinking that it only showed how wrong Goethe was. There is a reason that Goethe is viewed as one of the true geniuses of his age.
Thursday, June 10, 2010

Embarrassing moments include

Last week my former graduate student Ilya Berdnikov stopped by Oxford for a visit. Although the weather was a bit inclement, I wanted to show him the sights of the city of dreaming spires. (My tour of Oxford is getting pretty polished --- you can see some of the highlights from previous tours here and here). Undeterred by the weather, we dressed in foul weather gear – rain jacket, umbrella, boots – and started on our way.

One key part of the tour is to go to the top of the tower of the Church of the Virgin St. Mary. On the way into the church tower, you walk through the church itself. As luck would have it, a choir was practicing there, so we stopped to listen. Recognizing the conductor and some of the singers, I realized it was the Somerville college choir. (They did sound very nice in that space!) Bells should have gone off in my head at that point, but alas, they did not. I should have wondered why the Somerville choir was practicing in that church on that particular day.

We climbed up to the top of the tower and looked at the scenery for quite a while. The weather was perhaps starting to clear. It was cold and a bit drizzling but not uncomfortable up at the top. I mulled over “is that building Lincoln college, or is it that building?”, and pondered other geographical mysteries for quite some time. Then we started the long descent down.

As we neared the bottom we could hear the organ playing in the church. (I very much like organ music). The organ sounded a bit like a funeral precession. Loud bells should have been ringing in my head at this point, but alas… they still did not.

I opened the door to exit from the tower into the church and immediately stepped into a precession of my colleagues –- the Fellows of Somerville college –- coming into the church for a memorial service which I was supposed to be attending. The service was for the college’s former principal (and well known british spy) Baroness Daphne Park (you can read a very interesting obit here). All of the other Fellows of the college were wearing academic robes and black tie. I was dressed in my blue raincoat and hiking boots. I immediately turned bright red, turned around and jumped back into the church tower and closed the door behind me to hide in shame. I had completely forgotten that the memorial service was being held on that particular day. You might think that the choir and the organ music would have jogged my brain, but alas…

Anyway, we hid in the church tower for a moment trying to decide what to do next. It turns out that there is a back exit from the church tower into the café next door. Unfortunately, the exit door was locked, but I bashed on the door and pleaded with the café workers until they got a key and let me out through the escape hatch. But (alas), on the way out, I was caught by another fellow of the college who had been late for the precession (but was at least appropriately dressed) and who appeared to be trying to sneak into the church in exactly the same way I was sneaking out.

I’m not sure how many of the college fellows actually saw my faux-pas. I’m certain a few did. Fortunately, I think can get away with a few blunders like this one just for being an American.
Sunday, June 6, 2010

Congratulations to Rahul Roy

First of all, don’t try googling his name --- there is a famous Bollywood film actor named Rahul Roy. That is not the guy I’m talking about.

Last week Rahul Roy, a postdoc at Oxford (in my group, although mainly he works independently), won the prestigious McMillan award. This is a big deal. The award is presented to one young condensed matter physicist each year. (This year it was split for the first time ever, with Liang Fu, now at Harvard, winning the other half).

The work that was cited in this award was the theoretical prediction of Topological Insulators --- something I have blogged about several times before. See, for example, here.
I’ve often complained that many of the skills you need to succeed in science are not taught in graduate school. Rarely does anyone receive formal instruction in teaching, presenting, grant-writing, managing a group, or schmoozing --- which are all pretty important skills for practicing academics. Most of us eventually learn to do these things competently, even though these are not necessarily the things that we are really good at.

At Oxford, academics are expected to have skills that really stretch into the realm of the completely ridiculous. The reason for this is that each college is run (and in some ways owned) by its governing body –-- essentially the tenured professors (see the discussion here). As a result, we professors have to make decisions on everything from investing the college endowment to hiring the gardeners. We are certainly smart enough to realize that we know nothing about these things and as much as possible we try to consult people who actually do know something. Nonetheless, there are inevitably times when we have to ring-in on something that we know absolutely nothing about.

This week, Somerville College held interviews for a Deputy Head of Catering. In assembling the interview panel, it was deemed necessary that a certain number of members of governing body sit on this panel. Having avoided many odious tasks over the last year, this time I drew the short straw. So this week I sat through an entire day of interviewing caterers… as if I have any clue what these guys do. I suppose in some ways it was interesting: by the end of the day I learned that the caterers at Somerville actually do a whole lot --- from putting together the food for the students, preparing fancy formal meals, holding events and conferences, dealing with the health authorities (who randomly come by and inspect everything) and so forth. Obviously what I actually know about this profession is pretty close to nil. Yet I was still asked to form some sort of opinion about the candidates. Fortunately, there were two people on the interview panel who actually did know what they were looking for. I think I was there just for --- well, actually, I’m not entirely sure why I was there, but somehow it was deemed important that I be there anyway.

Never a dull moment…
Thursday, April 29, 2010

For your reading pleasure

Fiona Burnell and I have been working on a rather massive paper for almost two years now. Finally, this week, we declared it finished.

If you want know what it is about, you can read my short description here – or you can read the complete paper here, or you can read the reader’s-digest-massively condensed version here. If you don’t want to actually read it, you can just marvel at the cool figures.

Now, this is not the paper that has taken me the longest to write (My record in this respect was this paper, which I started with Gunnar Moller before he started graduate school, and we finished it almost exactly five years later when he was a postdoc). What is unusual about this paper is how long it is --– 35 small print pages: almost a third longer than any other paper I have ever published (not counting review articles). It feels really good to have it done.

What now? Time to write the next paper! .. and if you are the kind of person who reads this stuff, just wait til the next one… it gets even cooler soon!
Sunday, April 25, 2010

The Bells

When Paul Wiegmann visited Oxford early last year, he stayed in the cushy accommodations of the very weathly St. John’s college. Despite the luxury, he was seriously perturbed by the Bells of St. Johns.

“At 1 am they rang and woke me up. Then at 2am they rang twice and woke me up. Then at 3am they rang three times and woke me up…” ... and so forth.

My house (or “terraced”, as it is called) is very close to St. Barnabus Church. There are also hourly chimes at that church all night long, but I’m just far enough away that they don’t disturb me while I am sleeping (a block away is about enough, being that I’m slowly going deaf).

Bells at Oxford are just a fact of life you get used to. In addition to hourly chimes from everywhere, you frequently hear a bell cacophony that continues on and on for minutes, or even for the better part of an hour sometimes. You rarely know where these things are coming from, or why they are ringing in the first place. Many of the 40-something-odd colleges and halls have bell towers, as do many of the dozens of churches scattered around Oxford.

Perhaps the most impressive, if not the loudest, set of bells is at St Giles church, which is conveniently squeezed between the Theoretical Physics department and Somerville College, and can be heard very clearly from both. The bells in this church have an impressive history. The tenor F# bell dates all the way back to 1632 and bears the inscription


“Honar”-ing the king probably meant “do what the king tells you if you want keep your head”. “Feare”-ing God probably also meant, “do what the church tells you if you want to keep your head”. Perhaps “Learn to spell” would have been a good addition to the inscription as well.

Despite the ruckus caused by the frequently ringing of these bells, I confess to having a soft spot for bell-ringing. Back in high-school in Rochester New York, I was heavily recruited by several churches to be part of their bell-choirs. I was considered a choice recruit because I could read music well and, as an agnostic jew, I was always available on Sunday mornings. Admittedly, this was handbell ringing (See here or here), not real quasimodo-style bell ringing, but I’m not sure that any church in Rochester New York even has a proper bell-tower for that. The handbells were popularized as practice tools for their larger counterparts, but have now taken on a life of their own – particularly in sacred music, and in places where they don’t have real bell towers. At any rate, some of these bell-choirs were really fun to play in and they had talented musicians as their leaders. The down side was that I occasionally ended up having to sit through church services --- I guess the corresponding benefit of this was that I finally learned a bit about what goes on in churches (although it also more or less cemented my opinion that I was not really missing much as a non-church-goer). At any rate, I think I may have been the only agnostic Jew in high school who could quote new testament scripture.
Organization is not my strong point. Anyone who has seen my office, or my apartment can vouch for this. Starting my new life as a professor last year, I was worried that lack of organization – particularly in running a research group - might be my downfall. For me, in fact, the entire concept of research is fundamentally disorganized – and I’ve always felt that this is a good thing, since random wandering encourages random discovery.

Some professors do manage to run large organized groups. I think the larger the group, the more organized it has to be. Some even have detailed hierarchical structures, including lieutenants (pronounced “leftenants” over here), sergeants, and so forth. Each person has a unique and well defined project. Higher rank members oversee lower-rank members. They have group meetings periodically where one person reports on their progress, and research gets done very methodically. The top dog doles out the projects and sets the overall directions. The foot soldiers take their orders and produce the results.

But for many theoretical physicists that I know, this is not at all how research works. A more accurate description is that a researcher has some general field of interest and they simply mess around with ideas in that field until they figure out something interesting to work on. They work on this interesting idea for a while, two steps forward, one step back, and eventually do manage to make progress. But this type of messing around is not something that is easily organized. And it is particularly hard to oversee someone else’s messings and decide whether they are messing around correctly or not. Such researchers tend to have smaller research groups and tend to interact much more closely with their students and postdocs.

Of course when it finally comes time to publish discoveries, I do think it is very important to present a very organized picture of what you have found, and I do agonize over the organizations of my publications and talks. But this is more an exercise in covering your tracks and making it look like you knew where you were going all along.

Just sayin'...
Saturday, April 17, 2010

Volcano Woes

I’m used to having my travel schedule disrupted by all sorts of things: Thunderstorms, Snowstorms, Incompetent airline companies, Needing to saw a hole in my bed, and random other unforeseen circumstances.

This week’s unforeseen circumstance was a volcano – mount Eyjafjallajokul in Iceland. If you have not been following the news, I’ll fill you in: The massive amount of ash spewing from the volcano has dispersed across the skies of Europe and has completely shut down all air travel for thousands of miles around.

It figures it would be a volcano in Iceland. First they ruin their own economy, then they destroy the travel industry of the entire continent. This is hardly surprising from a country whose main industries are “fishing, dragons, and screaming” (if you don’t get that joke, look here Although if you live outside the US, you might not be able to stream this brilliant video. Try looking here).

Anyway, at the time of the eruption, I was in Ireland – just an hour flight from home. But alas, for the last three days, and for the forseeable future, no planes have been, or will be, moving. So the only way off the island was by Ferry.

(Random aside: I was amazed to discover that only about 12,000 years ago there were land bridges from Ireland to UK and from the UK to continental Europe. But alas, these bridges are now long gone).

Getting a reservation on one of the ferries was no mean feat. There are precious few ferries, and they quickly started to fill to capacity. (“Capacity” turns out to be far more than they can handle, since on a typical day, I’m told they run at about 10% of capacity – if that). Along with thousands of other people in the same predicament, I started franticly surfing the web trying to get a reservation. (Calling was beyond hopeless). There were very few web sites that would take reservations any more, and many of these sites were freaking out and crashing from the extreme traffic. After a few hours of searching, finally, for a brief moment, Fortuna smiled upon me, and I managed to nab a ferry reservation to Holyhead (Batman) in Wales, for the next day at 8am.

So at 6am Saturday morning I left Maynooth Ireland to go to Dublin Ferry Port. The scene there was hardly to be believed – people lined up to get on the ferries as far as the eye could see. You would think it was a rock concert or something.

Loading the Ferry, the Ulysses (appropriately enough for a Dubliner), was smooth enough. Show your reservation number, and walk right on. There was a guy there grabbing everyone’s baggage and throwing it onto a baggage carosel. Had I been thinking I would have refused to part with my luggage, but at the time I was just happy to be getting on the ferry. Huge mistake (more on this below).

The Ulysses itself is actually very nice. It seemed like it was actually a slightly re-configured posh cruise ship. Imagine the Love Boat, but a bit smaller. Now imagine taking the Love Boat and jam packing it with 1500 tired and grouchy people in a space more suited to about 100 people. (For those who might be interested, I spent the trip sitting in a corner reading appendix E from this massive article which I had the foresight to print out the night before. I only wished I had used a slightly larger font – my eyes are getting too old for the “print reduced by a factor of 4 so you don’t have to carry around too much paper” trick).

The seas were remarkably smooth, and the trip was very quick. This was not a coincidence. If the weather had been windy or rainy, the volcano ashes would have dispersed or found their way down to the ground as rain and air travel would have resumed. Alas, the unusual streak of fair weather and smooth sailing in Europe this month seems to have come at just the wrong time.

On the other hand, what was decidedly not smooth was the situation at Holyhead. The baggage carosel at the Holyhead terminal was set up to handle about a dozen bags, maybe a hundred,… not ten thousand. The masses of humanity squeezed into the arrival hall and complete confusion reigned. Just when we thought that maybe a few people were starting to find their luggage, the next ferry docked and complete confusion started all over again.

When I finally found my luggage after about an hour and a half (No exaggeration – I was cursing myself for stupidly allowing my luggage to be separated from me in the first place) I then had to find my way to the train. Of course there were thousands of other people with the same idea. The confusion was so complete in the station that it wasn’t even clear where the line for the train started and where it ended. I wandered around in the confusion for quite some time (you might think they would bring out a few extra police or rail workers to help with the situation, but no). As I got more frustrated, I debated getting a cab to take me to anywhere else besides Holyhead so I could reconsider the problem there. Just then a security officer came along and declared that I was standing in the line for the train tickets and just beyond that was, the train platform. He pointed only about 50 feet away to what was supposedly the front of the line. This was another rather lucky break. In only about 40 minutes I made it to the front of this line, grabbed my ticket and walked onto the next train. In another stroke of luck, the next train was direct to Birmingham – whereas many would have required at least two transfers. Fortuna was certainly smiling on me now.

I hesitate to think about how long some people must have been waiting to get on the train. The line stretched so long it was probably hours and hours before some of the folks at the back of the line got out of there.

Anyway, from Holyhead the journey was pretty simple. 4.5 hours to Birminham, short layover, and an hour from there to Oxford. I made it home by about 8 pm. I typically make it home from the US in much less time.

Next travel disruption? Earthquakes? Locusts?