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Posted in 2009

Twelfth lecture quantum transport

was the last regular lecture of the course. There will be a no-lecture #13 where I summarize the whole course and students ask questions: I have promised a prize of choice to a person who asks the biggest number of those.
There were several moments I stumbled during the lecture. One is when swithching from white noise to colorful environment: I guess I have to summarize what I want to do beforehand, the flow of the lecture makes a strange turn scattering attention of the audience. Second and third came close to each other: manifestations for decoherence/dephasing for electrons and dissipation mechanisms. Also, I was stressed in time when reached these transparensies. So that the disucssion of experiments was done in some hast.

Except this, the lecture was not bad. The attention/feedback was satisfactory. I even got an explanation why tau-phi is always bigger than tau-d. Actually, I’ve figured out it for myself only in the age of forty.

The Entry of the Most Holy Mother of God into the Temple

is one of the Great Feasts in Orthodox churches. Catholics call it Presentation and have celebrated it — right you are, two weeks ago. For me, it’s more like "entry", or more specifically, "braving stairs". Imagine a little child put in front of stairs with sufficiently challenging steps.(See this) You know what will happen: the child will climb up defying
gravity, possible inconveniences and minimal action principle. Not
thinking much about being at height. Just believing it is worth
climbing. So I hope I still climbe, and hope I do it in a right

In our parish, the feast is combined
today with another event circumstances of which are not completely
clear to me. Mayor of Amsterdam Job Cohen will visit our parish:
reportedly, to give a speech. I wonder if he climbs some stairs before
that: in fact, we do have some challenging ones. I look forward to more

Tenth lecture advanced quantum mechanics

was on disspative quantum mechanics. To summarize, I am reasonably satisfied both with my own presentation and the way the lecture has been received. I felt tired already from the begining but could stay it till the end. There was a time problem close to the end of the lecture so that we had to skip almost everything about density matrix and purity test. The attention was tight, and I got many question s about skipped hbars and missed i’s. 

There was a joyful noise from outside close to the end of the lecture. I had to get out and ask them to be quiter. Surprisingly, the guys making noise looked a way yonger than even first year students: wonder what did they do in the building. Perhaps they have been looking for their older brother/sister: a sound brust heard in 15 minutes might indicate they have finally found him/her.

# 11, the thoughest of the course, is nearing…


Quantum manipulation Josephson LED

I have submitted today an article to Nanotechnology, for their special issue on quantum things. This is collaboration with Leo Kouwenhoven and Fabian Hassler. Fabian Hassler has recently begun a postdoc carreer between Leiden and Delft in the framework of concentration group on quantum information. He is a citizen of Lichtenstein, the only one I know. He is supposed to divide his working time between Delft (to help experimentalists) and Leiden (to do theory?). He enjoyes having an office space in both cities.

Quantum manipulation of Josephson LED was a starting project of Fabian: to play with devices that are reasonably close to those in the fridges of experimental colleagues. He has accoplished this with speed of light: eight weeks have passed since the project formulation! Now we know how to produce entangled photon pairs on demand. We plan to go futher with Josephon LED research starting new year.

 You can see the article on Monday at



Eleventh lecture quantum transport

has been updated in time. I’ve made a majour reshuffle of the material and skipped a topic about Luttinger luquids. The fundamentals of dissipative quantum mechanics needed are explained at more qualitative and appealing level. There are still minor inconsistencies in powerpoints, but this did  not lead to any confusion. I am reasonably satisfied with the work done.

However, to put it frankly, I expected a better lecture. The interaction with the audience was at low level. Though not completely absent: the question about GQ has provoked some reaction. I did feel a certain mistrust, certain unwillingness to follow the lecture. Was it a fault of my presentation or the material still remains difficult to swallow?

If I get no comment, the question will remain for at least a year… 

Ninth Lecture Advanced Quantum Mechanics

was about coherent state and could easily be more coherent.  I still think the overall plan was good. Some words, side stories in the beginning. A simple realistic problem formulation: kicking an oscillator. Easy to solve at classical level. Need to sweat at quantum level. Solve. Analyze. Draw a circle. Then discuss coherence and coherent state in the context of laser. To finish: quick Cooper pair box as coherent states of particles.

I’ve started to slip up from very beginning. The citations and discussion of those suddenly appeared banal if not vulgar. Too much attention to beer: the students did not denomstrate any affection with the subject. I’ve felt the introduction that supposed to be both jovial and philosophical has been lost. Tried to compensate this by giving more attention to formulas and developed a time problem. The second half of the lecture has been hurried up, much to misunderstanding and mistrust. It looked like nobody believed me when I get to Cooper pair box.

There was however a question about coherence and coherent state, even before I was going to approach this topic. So I could recall Francis Bacon and his idol of the forum (gosh, I’ve said: daemon of the market, shoudn’t be that clumsy), a subject that in my mind every natural science student should learn by heart. There were more questions: the interaction with the audience was not a total disaster.





Thanks for 32,000 views

It is my pleasure to report another doubling of number of viewes. The past doubling took place 20 days ago while the blog is running for about 80 days. Thank you very much!

If I had more comments, I could easily beat the feeling that most hits are done by robots rather than humans.  Anyway…


More relics

to be found in Firenze, related to my post of Oct. 23.

Good news for all venerating science: Museum of History of Science reports acquisition of two more fingers and a tooth of Gallileo Galilei. Those have been lost for more than a century and will be on display in March when the Museum reopens. Naturally, after the acquisition the Museum will become Gallileo Museum.

Tenth lecture of quantum transport

was bad bad bad. Me bad. I have not given this lecture for two years: Yaroslav Blanter did it. When I gave it three years ago I sort of liked it. Indeed, the topic is hot (still):qubits. Most elements of the presentation were (and are) fine, the stucture is logical  and particular topics disscussed have been worth discussing. But perhaps I’ve changed too much in these three years: I did not fit the lecture, the lecture did not fit me, and that has been accumulating.

Shamefully,  I did not explain in time what  Rabi oscillation are, although they appeared on transparencies from time to time. Moreover, when a student dared to confront me with this natural question, I a. clearly indicated I did not like the question b.instead of answering, utter a short side-story c. finally, gave clusmy, long and incomprehensive answer. Bet I looked like an ambitious fool. Just appearence: my ambitions are modest.

The main problem was that I really hated the sheets. They did not contain what I needed, instead, they contained a lot of things I did not need. In the course of the preparation I recognized the problem, and went through the set three time to find a reconciliation between me and the lecture. It looked like we reached an agreement. However, the transparencies betrayed me somehow. 

Down with the set, will never use it again. Qubits is a rapidly developing topic anyhow, the lacture must be updated.



Crux II 2

I have skipped the last meeting of our christian society. It appeared that many people have skipped that as well, and the organizers have encouraged us "to keep the flame". So I did my best to attend the meeting on November 19, despite overlapping appointments.

It was interesting. Karel Terwel told us about his parish in Delftshaven: old town being now a part of greater Rotterdam. It dwels in a neat old church ( The parish life is active and flourishing, including missionary and social work in the town. It was nice to learn that the parish is growing and full with young families.

Karel is a busy person: he is a teacher at TU Delft, he is a chairman of the parish council, and, as if it is not enough, he does a PhD study. He hardly has a free evening, and feels bad about: he thinks he should do more for the parish. He got various advices. For instance, it was noted that his TU Delft activities whlist done properly, is also work for God, since He dispatched Karel to Facultly of Civil Engineering. Another advice was not to do PhD studies in the evening: right, evenings are hardly productive as far as intellectually involved work is concerned. A PhD student has compared his lifestyle with that of his Chineese (en thus unbelieving) fellow-students to conclude: they’ve more time to work, it costs time and perhaps quality of PhD thesis to be a Christian.

Well, at least for me the time spend on the meeting was not a waste on expence of my work: I was freshly recharged by seeing my friends in Christ and praying with them. Glory to God.

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