Discord Day at Benasque

I’m at Benasque, Spain for the Quantum Coherence and Decoherence 2010 conference. The participants are people I feel I should have met a long time ago. Also, the center is in a beautiful new building with many areas for discussion, all with blackboards.

This is my first time at Benasque, and the philosophy of the conference is great: this is a place for people to meet and get new collaborations going. The program is informal, but well attended. The talks are decided depending on the group’s interests. Yesterday, it was Discord Day:

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If you want to succeed in the world, you don’t have to be much cleverer than other people. You just have to be one day earlier.
-Leo Szilard

Quantum Minesweeper

If you are vaguely interested in quantum mechanics, you must check out the game Quantum Minesweeper. You might want to start with the video tutorial before you play online.

The game differs from classical Minesweeper in the following ways:

  • The board is really a quantum superposition of two boards. It is your goal to figure out the superpositions. It is simplified, as only one kind of phase is allowed.
  • There are three different kind of measurements that you can do, each one a limited number of times. The measurements are:
  1. classical measurement – collapse that can trigger a mine probabilistically. Very risky!
  2. entropy measurement – it indicates if there is a superposition or not, but doesn’t tell you if there is a mine or not!
  3. interaction-free measurements – it is very magical, doesn’t collapse the wave function, actually gives you the phase information. Very powerful!

This game is fantastic!

Technical digression:

I have a question that might be a good undergraduate research project for someone interested in quantum information. What is the optimal strategy for the game? That is, if you thought of this game as a kind of state tomography problem, is there a general protocol to extract the state with high fidelity, given the constrains of the number of measurements? To make it more interesting, imagine a version of quantum minesweeper where the boards could have between them any kind of phase, how much harder would solving it be?

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Give it one last try
til the next
one more
last try.
-A Wilhelm Scream

Dirac and Quantum Mechanics

Dirac invented quantum mechanics as we know it. He unified everything, adding much along the way into the modern formalism. His book from The Principles of Quantum Mechanics feels completely modern,although it was first published in 1930. However, he was also very humble, giving a lot of credit to others for things he himself discovered.

Kurt Gottfried posted a paper in arXiv:1006.4610 where he carefully examines the history of quantum mechanics by going to the original papers and getting the record straight. This highlights the central role Dirac played through out this. This cute paper is nice, with tons of references, some fun anecdotes, and just enough equations to get the details right. I highly recommend it.

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Time flies like an arrow. Fruit flies like a banana.
-Groucho Marx

Sudarshan gets the Dirac Medal

On Dirac’s birthday, I would like to congratulate E.C. George Sudarshan, for being awarded the Dirac Medal! George is one of the most important physicists of the last 60 years, whose work includes the discovery of the weak interaction (one of the four forces of nature), the formulation of the diagonal representation of quantum optics (discovering the “quantum” in optics), the discovery of the quantum Zeno effect (a watched pot never boils), the theoretical formulation of the faster-than-light particles called tachyons (take that Einstein) and the development of the foundations of open quantum systems (my personal favorite, as I did my Ph.D. with him on this subject).

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John McClane: Yippie-ki-yay!

Radiation, Boo!

New Scientist has an article, Who’s afraid of radiation?, with an overview of the history of regulation of radiation dosage and its impact on human health. It works as a nice follow up to my own post The Nucular Family.

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Radio does not, in general, go around corners. This can be a real pain when you are conquering the world, which is inconveniently round, placing all of your most active military units over the horizon.
-Cryptonomicon

Video: Quantum Effects in Photosynthesis – FermiLab

The video and slides for my talk for undergraduates at FermiLab can be found here:

Quantum Effects in Photosynthesis [RealPlayer video link].

This is a good introduction to my research. If you are curious about what I do, by all means watch it.

[I know RealPlayer is so 1998 and sucks, I’m trying to get the file in another format from the FermiLab people.]

[Previous post here.]

Visiting FermiLab

Ten summers ago I was an intern in FermiLab, then the largest particle accelerator in the world. I had a fantastic time working with my mentor, Chandra Bhat, to figure out how to accelerate anti-protons in the Main Injector. That summer I learned a lot of physics that motivated me into pursuing a graduate degree in physics. I also made friends I still keep (and even publish with!). And, I was in the poster.

Can you spot me? Hint: Babyface, clean shaven, short hair.
Can you spot me? Hint: Baby-face, clean shaven, short hair.

Yesterday, I went to visit the lab! The organizer from the program, many whom are still working since back in the day, were very kind to invite me there. It was fun to see Naperville again (it hasn’t changed much, suburbia has been yuppiefied a bit) and FermiLab itself (still the same!). I gave a talk titled Quantum Effects in Photosynthesis to a standing-room-only audience of summer interns, high school students, high school teachers and more. It was fantastic to see everyon again, and to interact with the very gifted students. The best questions came from the high school students who seem like they will become very talented scientists and engineers.

SciAm on Dirac

The Theorist of Theorist, the first modern physicists who decided theorists were at the forefront of physics, the great P.A.M. Dirac, is the inspiration for the title of this blog, and is one of my heroes!

If you are even slighty curious of who Dirac is, you must know that Steve Mirsky of Scientific American recently interviewed Graham Farmelo, author of the authoritative biography of P.A.M. Dirac, The Strangest Man: The Hidden Life of Paul Dirac, Mystic of the Atom. The interviews is fantastic, full of incredible insight from Graham Farmelo about Dirac’s life and a surprising deep understanding of the importance of Dirac’s work by Steve Mirsky. The interview can be downloaded free online: Part One and Part Two. The funny anecdotes alone are reason enough to check this out. This is the best science interview I have heard in a long time.

To celebrate this interview, SciAm has posted online the article written by Dirac for Scientific American published on 1963. Amazing stuff!

SciAm: If you do this a couple more times, you might inspire hope on me that there might be some good science for laymen magazine out there that isn’t crap.

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God used beautiful mathematics in creating the world.
-P.A.M. Dirac