Weblog Yuli Nazarov
Kavli Colloquim Immanuel Bloch
has taken place today. Immanuel Bloch is a (relatively yong) professor in Munich doing very interesting and important experiments on trapping ultra-cold atoms in laser lattices. I must say that usually I feel a certain repulsion to this field/topics due to the reasons I would not discuss now. By no means this applies to Immanuel Bloch. He gave and interesting and brisk talk, very clear even in details, and made an effort to explain the physics involved. This is given the fact that he’s so much to say: he had to subdivide the talk into six "chapters", each being devoted to a distinct experimental situation. He’d no bombastic or excessively ambitious statements, and he did not have to since the quality and quantity of his research spoke for itself.
My task for today was to moderate a mini-symposium with local speakers, a kind of warming-up session for Immanuel Bloch. Katja Nowack, Jos Thijssen and Val Zwiller gave 10+5 minutes presentations. Since nobody at our Institue does ultra-cold atoms, the topics could not be a perfect match. Howewer, the essence of ultra-cold atoms is quantum statistics (Katja) many-body physics (Jos) enabled by optical tools (Val) so it all went coherent.
To complete the pleasure, we’ve also got cake in the break and drinks afterwards.
Fairly tales of theoretical physics
will be the name of a new course given in spring semester 2011. Except the name, there are several unusual things about it.
First of all, this will be a collaboration of all members of our theory group. Everybody will entousiastically contribute 2-3 lectures. We are glad that we can do such things together and one of the goals of the course is to show that we theorists are present at this, well, mostly technical, University.
We are also grateful to a person who kind of made everything for us so we won’t overstress ouerselves while preparing to the lectures. David (Dima) Khmelnitskii, long-time faculty of Cambridge (REAL Cambridge, of course) is giving this course over there for quite a time. (see http://www.tcm.phy.cam.ac.uk/~dek12/) "Fairy tales" is a very accurate description of the specific manner he’s chosen for presenting selected topics on mathematical physics. It’s been considered as a tough course among Cambridge (real Cambridge) students. Let’s see how does it go in Delft.
Two of us know Dima for a long time, that allowed him to appreciably contribute to our education (in that particular case, NOT in real Cambridge) as well in our understanding of the essence of theoretical physics. We will be honoured to give his course.
30
is another round number of personal significance. That many years ago I married Elena who is still kind enough to remain my spouse. In the beginning, our union was of pure civilian nature. Ten years ago we decided to involve Church into our personal relations. And we re-married in a course of a traditional rite, long and sacramental. It was a wonderful feeling of re-marring your own wife: I would not mind to do it again and again.
Spin superconducting qubits
have been accepted for Physical Review B. Guess we could make it for PRL, but the article got a way too long. This will be a first journal publication of Ciprian Padurariu: felicitări, Ciprian.
To make sure that a less attentive reader would not occasionally mix up our theoretical research with actual experimental realisation, the editors have changed the title to "Theoretical proposal for superconducting spin qubits". They must have had good marks in German at school.
50
So I’ve turned fifty. Silly, isn”t it? I feel unprepared. I’d need 20-30 years more to train for this day an meet it as I imagined it 20-30 years ago: with a feeling of significant accomplishment. Well, this I’ve not. Instead I regret I’ve wasted so much time. Thanks to all I met during the period: when I recall you, the regret gets away.
Advanced Statistical Mechanics
As mentioned, I will be giving a different course starting spring 2011: Advanced Statistical Mechanics. Today I have made some decisions concerning the structure. One of the goals is to provide backward compatibility with the course of Jos Thijssen sucsessfully given for a number of years.
Book: I decided to go for most popular books for a course of the kind: those of Mehrar Kardar. This was not a simple decision since the books are thick, written in a more scolastic style than I’d like, provide the coverage that is more broad than interesting, and cost seventy-nine silver pounds. Many teachers that use the books complain about inconventional notations. Still the books are adopted in most prestigious American universities. So finally I got in terms with those.
Topics: since the books are too thick, one has to make a selection of topics. The present selection of Jos Thijssen is very logical and will be taken as a basis. However, owing to unavoidable taste differences I’d rather resize the relative volume of the topics. For instance, I’d like very much to talk about the correspondence between classical 1d stat-mechanics and 0d quantum mechanics, while ideal gases do not appeal to me that much.
Easter
Christ is risen!
Blessed Easter to you, dear reader. I’d like to make an exception from no-image rule for this blog and let you see my favourite icon of Resurrection. This icon is situated in a small russian-orthodox chapel in Dachau, Germany, and refers to Easter celebration on May 8th, 1945.
(see http://www.orthodoxytoday.org/articles/RahrDachauPascha.php)
Good Friday, Holy Saturday
Just attended Matins of Holy Saturday, celebrated Friday evening. Wish I had words.
From Troparia
The One, who of old hid the pursuing tyrant in the waves of the sea, the children of those he saved have hidden beneath the earth; but let us, like the young maidens, sing to the Lord; for he has been greatly glorified.’
Lord, my God, I will sing a song for your departure, a funeral hymn for you who by your burial opened up for me the entrances to life, and by your death put Death and Hell to death.
All things above the world and all below the earth quaked with fear at your death, as they saw you on the throne above and below in a tomb; for beyond understanding you appeared as a one dead, you the source of life.
That you might fill all things with your glory, you went down into the lowest parts of the earth; for my substance, which is in Adam was not hidden from you, and by being buried you make me, who had been corrupted, new, O Lover of humankind.
Measuring entanglement
I cannot believe it myself, and it is hardly thustworthy to write about it on April 1, but please take it for a fact. I have attempted to experimentally quantify entanglement of photon pairs today. I did not do any experiments for more than thirty years.
Val Zwiller is to blame. When asked to provide an experimental setup for undegraduate lab practice, he could not come with any fresh idea. So he’s just slightly modified a setup of pioneering experiment of Alian Aspect who has quantified the violation of Bell inequality in 1981. He has invited me and Leo Kouwenhoven to "inagurate" – that’s how he put it – the experimental setup.
At 16:00 I was at his office. We brisky got to the measurement room. On the way Val asked me with soft heartfelt tone: " Do you believe in entanglement? Do you believe in non-locality?" This gave me a thrilling impression of being a part of important rite: he sounded like a priest asking faithful about their readiness. "I do. I do believe." I responded, trying to match the tone. I wanted to add that I believe in quantum mechanics, but, given the nature of the rite (where a participant should demonstrate a ritual doubt and sucsessfully overcome it by direct measurement) this would not sound polite.
Me and Leo have been supervised by Julia Cramer and another young lady. The setup was placed in two large plastic boxes alike my children use to store old toys. One box housed a blue laser, non-linear crystal to chop a blue photon into an entangled pair of red ones. The two go by two fibers to the second box where their polarizations have been rotated by changeable angles and finally get to photon counters. The computer gave coincidence counts, those depending on the rotation angles. The math to be made afterwards, and its significance is explained in http://en.wikipedia.org/wiki/CHSH_inequality.
There were about twenty curious people in the room, all irradiating excess heat. Val has attibuted the chaotic work of the setup to this mere circumstance. He kept re-tuning the fibers in the production box. He did it quickly and efficiently. I was turning polarizers. Leo read data and wrote it up. One needs to measure at four different positions of the polarizers. So we got 16 readings. After the experiment everybody was cheering while I had to do the math.
We did not manage to prove (our faithful devotion to ) quantum mechanics this time. This would happen if the final answer would exceed classical boundary of 2. Yet we got 1.91: Almost. Not bad for the first time.
Thanks very much, Val, Julia and all others involved: this was a wonderful and entertaining experience for me, and it will be fun for many generations of students.
No proposal NWO-nano
Finally I decided not to send my nanoelectromechanical proposal for national NWO-nano granting tour. I feel guilty about this, and reckon that the decision is wrong. I have a set of nice clear ideas that wait to be explored for common good, and I would be a right person for this research. I think I would be able to write a sucsessful grant application on the topic.
The reasons I do not do this are mostly psycological. The competition has a set of scary rules seemingly requiring immediate utilization of the research in a form of Taiwan-made gadgets( while still supporting Dutch economy). If literally read, the rules forbid any theoretical research. My colleagues at the department were hesitant to endorse and/or support my ideas and did not propose any collaboration. As I wrote, I have recently had a depression wave and thus had no desire to work.
I understand little relevance of all these factors. If I only had an extra week or perhaps two to work on the proposal and gain self-confidence needed… Ok, perhaps I can use the material for the next grant round.