Last week, my friend Luis came through town, with…a two faced calf named “Unique”:
We went for drinks at the Pink Adobe, $3 cover charge, the band playing loud Led Zeppin covers, and then some of my collegues from the Santa Fe Institute wanted to see what Luis had in the back of his big SUV in a trash can. In the dark parking lot behind the bar, Luis and crew unfolded from its plastic rapper the two faced calf. 17 days it lived, too short, I say, too short. We gathered around, freezing in the cold Santa Fe night, to stare at the two faced calf which itself was frozen and packed in ice. And the entire time, as we gawked and stared, the security guard stationed in the parking lot, he didn’t move a bit.
Somedays, life feels like it should be part of a novel. Other days, it seems even more interesting.
QCSS05
The dealine (March 15, 2005) for the Summer School on Principles and Applications of Control in Quantum Systems to be held at Caltech on August 7-14, 2005 is fast approaching. If you’ve ever wanted to learn how to apply control theory to quantum systems, this looks like an amazing opportunity. The potential agenda includes:
- Experiments and applications for control in quantum systems – phenomenology and motivations for control
- Applications of optimal, relaxation-optimized , and ensemble control in magnetic resonance
- Quantum feedback control in atomic systems: applications to precision measurement
- Quantum control applications in quantum information science
- Quantum dynamics of superconducting circuits and circuit quantum electrodynamics
- Quantum measurement and feedback with nano-electromechanical systems
- Quantum-physical modeling
- Quantum mechanics in the Schrödinger, Heisenberg and Interaction pictures
- Perturbation theory and master equations
- Quantum probability and filtering
- Control theory: from classical to quantum
- State-space modeling; introduction to optimal and robust control
- Geometric control: overview and highlights
- Stochastic control: overview and highlights
- Control-theoretic model reduction
- Frontiers in quantum control
- Presentations on latest research by leading practitioners in the field
Disordered Personality
Ever wonder what peronsality disorders you have. Via Pharyngula I have come across the totally unscientific, but interesting Personality Disorder Test.
Disorder | Rating |
Paranoid: | Low |
Schizoid: | Low |
Schizotypal: | Low |
Antisocial: | Low |
Borderline: | Low |
Histrionic: | Moderate |
Narcissistic: | Moderate |
Avoidant: | Low |
Dependent: | Low |
Obsessive-Compulsive: | Moderate |
— Personality Disorder Test – Take It! — |
It looks like I’m a self-centered clown with obsessive-compulsive tendencies. Jez, this test makes it sound like I’m Woody Allen.
Pavlovian Dave
When I was in high school I taught myself the physics necessary to take the AP physics exam. I did this by taking a physics textbook and doing all of the problems which had solutions in the back of the book. At the time I was doing this, I had just discovered Dire Straits “Brothers in Arms” album and that is ALL that I listened to when I was working on these problems. When I went off to college, I was sitting in my dorm room one day when I put on the Dire Straits and all of the sudden I notice I had this amazing urge to do physics problems. I had trained myself to do physics whenever I heard that one CD. It was as if Pavlov’s dogs had suddenly learned to do physics.
So now I actually use this technique to get work done. I play a single album or a single song over and over again when I’m working on a particular subject. Then, if I ever have a problem getting working on that particular topic, I pull out the appropriate song and whamo, I can’t help myself from getting work done.
Here is this month’s song for conditioning myself to get work done:
Placebo: “Protect me from what I want”
It’s that disease of the age
It’s that disease that we crave
Alone at the end of the rave
We catch the last bus home
Corporate America wakes
Coffee republic and cakes
We open the latch on the gate
Of the hole that we call our home
Protect me from what I want…
Protect me protect me
Maybe we’re victims of fate
Remember when we’d celebrate
We’d drink and get high until late
And now we’re alone
Wedding bells ain’t gonna chime
With both of us guilty of crime
And both of us sentenced to time
And now we’re all alone
Protect me from what I want…
Protect me protect me
Hans Bethe 1906-2005
Yesterday the great theoretical physicist Hans Bethe passed away at the age of 98. Details can be found here.
Whenever I’m traveling and I’m trying to work on a plane, I think about Bethe. Because in 1947, Hans Bethe, on the trainride back to Schenectady, made the first rough calculation of the Lamb shift. And today, when we rush around the world, jetsetting our way from conference to conference, I often wonder if we slowed down, and took the train, whether physics wouldn’t be better off.
Then, of course, there is the famous Physical Review 73, 803 (1948), “The Origin of Chemical Elements” by R. A. Alpher, H. Bethe, and G. Gamow. I’ve always dreamed of finding a coauthor with a suitable last name to go with my food item last name “Bacon.”
Finally, there is this amusing story of a conversation between Bethe and Leo Szilard:
The physicist Leo Szilard once announced to his friend Hans Bethe that he was thinking of keeping a diary: “I don’t intend to publish. I am merely going to record the facts for the information of God.”
“Don’t you think God knows the facts?” Bethe asked.
“Yes,” said Szilard. “He knows the facts, but He does not know this version of the facts.”
CEPI Seminar 3/9/05 – Ben Schumacher
Ben Schumacher, quantum informationista extraordinare, and inventor of the word “qubit” will be givin the next Complexity, Entrophy, and the Physics of Information Distinguished Lecture at the Santa Fe Institute this Wednesday, 3/9/05, reception at 4:15, talk starts at 5:00:
Information Engines and the Second Law
Ben Schumacher
Department of Physics, Kenyon College
Maxwell’s demon, which extracts work from a thermodynamic system by acquiring information about it, has for more than a century been a favorite thought-experiment in the foundations of statistical physics. The demon has variously been viewed as a threat, an exception, an exemplar, and a means for extending the Second Law. I will describe a new formulation of thermodynamics in which such “information engines” play the central role, giving new insights about entropy, information erasure, the meaning of temperature, and the connection between fluctuation and dissipation.
Optimality Feels Good
New paper! New paper! Let’s all do the new paper dance. Posted to the arxiv today: quant-ph 0503047. This paper is a revision of an earlier paper, where now it is shown that the protocol in the earlier paper is in fact optimal.
Optimal classical-communication-assisted local model of n-qubit Greenberger-Horne-Zeilinger correlations
Authors: Tracey E. Tessier, Carlton M. Caves, Ivan H. Deutsch, Dave Bacon, Bryan Eastin
Comments: This submission supersedes quant-ph/0407133. It is a substantially revised version of the previous document and now includes an optimality proof of our model
We present a model, motivated by the criterion of reality put forward by Einstein, Podolsky, and Rosen and supplemented by classical communication, which correctly reproduces the quantum-mechanical predictions for measurements of all products of Pauli operators on an n-qubit GHZ state (or "cat state"). The n-2 bits employed by our model is shown to be optimal for the allowed set of measurements, demonstrating that the required communication overhead scales linearly with n. We formulate a connection between the generation of the local values utilized by our model and the stabilizer formalism, which leads us to conjecture that a generalization of this method will shed light on the content of the Gottesman-Knill theorem.
Day 9
It’s been far too long since my last ski trip. Yesterday I went skiing at the Santa Fe Ski Basin. It’s amazing what a small amout of new snow can do to make the conditions enjoyable. Steve Flammia came up with following interesting question: “How many chairs (what percentage) do you pass on your way from the top to the bottom of the chair lift?” [correction: As Joe points out, I somehow managed to totally mangle this question. Of course the question should be how many chairs you pass on the way from the bottom to the top of the chair. God Mondays are rough.] Make a first intuitive guess without thinking about the problem. I’d love to hear what people’s first guesses are in the comments.
Stop Blaming the Bugs
I just got through watching the movie “The Butterfly Effect.” (decent movie, I could probably form a religion from its basic plot.) The name of the movie comes from a statement you sometimes hear from those who work in chaos theory:
The flapping of a single butterfly’s wing today produces a tiny change in the state of the atmosphere. Over a period of time, what the atmosphere actually does diverges from what it would have done. So, in a month’s time, a tornado that would have devastated the Indonesian coast doesn’t happen. Or maybe one that wasn’t going to happen, does. (Ian Stewart, “Does God Play Dice? The Mathematics of Chaos”)
And I have to say that I’ve never understood what I’m supposed to take from this statement. Sure many systems are chaotic and we can have large differences in behavior from seemingly small changes in the initial conditions. But I sometimes get the feeling that a causal relationship is being made in this statement: if it weren’t for the butterfly, the people in the path of the tornado would be fine, i.e. the butterfly caused the tornado. But this clearly isn’t true. There are plenty of other effects which are also casually necessary for the tornado. Do I get to blame the butterfly if an even smaller change in the wavefunction of single proton somewhere in the upper atmosphere changes the initial conditions by even a smaller amount than the butterfly and this in turn changes the entire outcome of whether there is a tornado? In fact, I would argue that we can only blame the butterfly if other changes in initial conditions of comparable size do not change the outcome of whether there is a tornado or not. Chaos may be ubiquitous, but I wish we’d all stop blaming the butterfly.
Probability of Greatness
An amusing anecdote from cond-mat 0305150 by Simikin and Roychowdhury:
During the “Manhattan project” (the making of nuclear bomb[sic]), Fermi asked Gen. Groves, the head of the project, what is the definition of a “great” general. Groves replied that any general who had won five battles in a row might safely be called great. Fermi then asked how many generals were great. Groves said about three out of every hundred. Fermi conjectured that considering that opposing forces for most battles are rougly equal in strength, the chance of winning one battle is 1/2 and the chance of winning five battles in a row is (1/2)^5=1/32. “So your right General, about three out of every hundred. Mathematical probability, not genius.”