Monthly Archives: January 2005

Ghost Council [Open Thread]

I’m late with the open thread, but hey, it was a three-day weekend.
Space Ghost Coast to Coast: Volume 1: This of course is Cartoon Network’s hilarious talk show, hosted by 60’s Hanna Barbera superhero Space Ghost. A typical episode involves Space Ghost conducting absurdist interviews with celebrity guests who appear to be under the influence of controlled substances, while various cartoon mayhem rages around them. The best episode so far is “Girlie Show”, in which Space Ghost decides to give a tribute to women, and so invites Fran Drescher, Carol Channing, and “rock and roll riot grrl Alice Cooper”.
Iron Council: (Follow-up) Although I didn’t enjoy this as much as Perdido Street Station or The Scar, it was still a good read. It did pick up toward the end, moving toward a climactic boss battle (to use video game terminology) that was the high point—but there were about a hundred pages left after that, so the pacing was a bit weird. Still, the ending was satisfying. There were lots of sly references to Station throughout the book, which was fun, but I would have liked to see some follow-up on Scar as well—perhaps a sighting of my favorite Miéville character, Bellis Coldwine.
Funeral: This album got a lot of buzz in indie-rock circles last year, so I finally just picked it up. And hey, it’s pretty good! Intense and passionate, and multilayered; “Crown of Love” sounded like a standard (if well-done) love anthem until I read the lyrics closely and realized that some of the lines I couldn’t make out put it in a rather different light. My favorite song is probably “Rebellion (Lies)” . (Apparently their live show is pretty good as well.)

Women in the Sciences

Matt Yglesias has a funny yet insightful post on the recent infamous comments from Larry Summers:

Now in my experience with any dorky, male-dominated activity, the problem is this: Every time a woman begins to participate in the dorky, male-dominated activity, she is immediately pounced upon by dozens of dorky, unappealing men. Some people have sufficient commitment to electrical engineering (or blogging or philosophy or whatever) to press forward nevertheless. The faint of heart, however, are driven away by the nerds never to be seen again.

I’m impressed that a Harvard alum could so eloquently summarize the Caltech gender dynamic. After you read his post, follow the link to PZ Myers’ equally good remarks on the subject.

Flickr post: Tilden Park

clouds
Yesterday I went hiking in Tilden Park. (It’s like 2 miles from where I live–why haven’t I done this before?) I came back with a number of photos (posted to Flickr here) and one weird story.
So I’m walking up Meadows Canyon Trail, and I see two women coming the opposite way: one is blindfolded, a hand outstretched, and being led by the other. As I approach, the latter develops a slightly evil smile and starts making hand signals at me which I find difficult to interpret. It turns out she’s telling me not to speak, which is something I excel at anyway. She leads her companion up to me, and I start to understand; the blindfolded woman senses something in front of her and retracts her hand, but the other takes her wrist and places her hand on my shoulder. I’ve got the idea by now and am holding my breath so as not to give away the game. She seems confused by my denim jacket, moves her hand past my collar and to the bare skin at my neck. Jumping back, she yelps, “oh my god it’s a person!” and I release my breath in a burst of laughter. The guide (also laughing) leads her down the path and thanks me as we pass.
Anyone know what this was about? Under what circumstances does one find oneself being led blindfolded down hiking trails?

Quantum scheduling

I was thinking about schedule conflicts today, and it occurred to me that as a physicist working in quantum coherence, such things shouldn’t be a problem for me. I should be able to build some Miévillian device to go to multiple events at once. And then I realized that I already have such a device: the qubit we currently study has this capability.
Consider what I hope will remain a purely hypothetical situation: a friend’s wedding in Los Angeles being on the same day as my brother’s graduation in Chicago. I’d like to go to both places, so I go into the lab and prepare to measure the qubit. A measurement of a qubit can have two possible outcomes, which I will call 0 and 1: these correspond to clockwise and counter-clockwise currents in a loop of superconducting aluminum. Ahead of time I decide that the outcome of the measurement will dictate which event I go to: if 0, I go to Chicago; if 1, I go to LA.
Next I apply a pi/2 pulse to the qubit. This is a pulse of microwave radiation tuned to the qubit’s resonance frequency, over a time duration designed to rotate the qubit 90 degrees (pi/2 radians) on the Bloch sphere, which puts it in a superposition state of 0 and 1. So the qubit is in both states simultaneously. Now I make the measurement.
According to the many-worlds interpretation, what happens when I make the measurement is that there are two parallel universes: in one I measure 0 and go to Chicago, and in the other I observe 1 and go to LA. Success!
(Unfortunately, another way of looking at it is that there are two parallel universes, one in which I don’t go to Chicago and one in which I don’t go to LA. On average I’ve still only gone one place. If only I could entangle myself with the qubit without causing decoherence…)

2005 APS March Meeting

The bulletin for the 2005 APS March Meeting is up. Here’s the abstract for my talk, scheduled for 11:39am on Friday, March 25.

Abstract: Y16.00003 : Quantum Coherence in a Superconducting Flux Qubit
Authors: T. Hime, B.L.T. Plourde, P.A. Reichardt, T.L. Robertson, C.-E. Wu, John Clarke, (University of California, Berkeley)
We report observations of quantum coherence in a superconducting flux qubit. As the flux applied to the qubit was swept through the degeneracy point, $(n+1/2)\Phi_0$, we could resolve the change in qubit screening flux produced by the reversal of the qubit circulating current. By applying microwave radiation to the qubit, we observed resonant excitation when the qubit level splitting matched the energy of the microwave photons, corresponding to a change in the qubit screening flux. We varied the microwave frequency and mapped out the dispersion of the excited state transition which fit well to the expected hyperbolic dependence. With high-resolution spectroscopy, we measured anomalous structure and splittings on the excited state line, which may correspond to coupling to defect states in the junction tunnel barriers. We performed coherent manipulation of the qubit state by applying microwave pulses of fixed amplitude and frequency, but variable width. This resulted in Rabi oscillations with a Rabi frequency which scaled linearly with the amplitude of the microwave pulses.

The Clarke qubit group is giving three other talks in this session as well:
Y16.00002 Flux Qubits and Readout Device with Two Independent Flux Lines
Y16.00004 Measurements of Dephasing in Superconducting Flux Qubits
Y16.00005 Measurements of Relaxation in Superconducting Flux Qubits
The meeting is in Los Angeles this year, so I will be dropping by Pasadena: certain readers should consider themselves warned.

Friday Catblogging Returns!

I have convinced another stray that I am not a threat, by moving real slowly like Robert Redford in Sneakers. Once he* decided I was friendly, he immediately demanded to be let inside. He refused to sit still for a picture, so every shot I took was blurry except for this one of him eyeing a comfortable spot on my couch:
friday catblogging
*Again I use “he” generically, since I have respected this cat’s privacy.

Flickr post: dilution refrigerator

There was some interest in pictures of equipment I actually use, so I’ve uploaded a couple of the fridge.
dilution refrigerator
A dilution fridge works by diluting one isotope of helium (helium-3) into another (helium-4), a process which absorbs heat under the right conditions. Excess helium-3 is then pumped off the top of the mixture and run in a closed cycle back into the dilution. I’ve used Flickr’s notes to label various parts of the apparatus; click on the image here and then mouse over it on the Flickr page to see the annotations.

Technology marches on

Via Warren Ellis:

Samsung Develops World’s 1st ‘Motion-Recognition’ Phone
SEOUL, Jan. 12 (Yonhap) — In the latest of a series of innovative product developments, South Korea’s Samsung Electronics Co. said Wednesday it has developed the world’s first mobile phone with motion-recognition capability.
Using a six-axis sensor that it says can interpret simple human motions, the SCH-S310 phone allows users to dial phone numbers by writing the numbers into the air instead of pressing buttons, Samsung Electronics said in a statement.
The new device also enables users to delete unsolicited commercial text messages by shaking the phone up and down, the company said.

I would buy it just for that feature.