Two papers in one post this time out. One of these was brought to my attention by Joerg Heber, the other I was reminded of when checking some information for last week’s mathematical post on photons. They fit extremely well together though, and both relate to the photon correlation stuff I was talking about last… Continue reading Bunches and Antibunches of Atoms: Hanbury Brown and Twiss Effects in Ultracold Atoms
Category: ResearchBlogging
Measuring Temperature by Counting Atoms: “Suppressed Fluctuations in Fermi Gases”
When one of the most recent issues of Physical Review Letters hit my inbox, I immediately flagged these two papers as something to write up for ResearchBlogging. This I looked at the accompanying viewpoint in Physics, and discovered that Chris Westbrook already did most of the work for me. And, as a bonus, you can… Continue reading Measuring Temperature by Counting Atoms: “Suppressed Fluctuations in Fermi Gases”
Quantum Mechanics Is Square: “Ruling Out Multi-Order Interference in Quantum Mechanics”
This week’s big story in physics is this Science paper by a group out of Austria Canada (edited to fix my misreading of the author affiliations), on a triple-slit interference effect. This has drawn both the usual news stories and also some complaining about badly-worded news stories. So, what’s the deal? What did they do… Continue reading Quantum Mechanics Is Square: “Ruling Out Multi-Order Interference in Quantum Mechanics”
Protons: Even Smaller Than We Thought
The big physics story at the moment is probably the new measurement of the size of the proton, which is reported in this Nature paper (which does not seem to be on the arxiv, alas). This is kind of a hybrid of nuclear and atomic physics, as it’s a spectroscopic measurement of a quasi-atom involving… Continue reading Protons: Even Smaller Than We Thought
Kids These Days: Is Our Learning Measure Valid?
Kevin Drum has done a couple of education-related posts recently, first noting a story claiming that college kids study less than they used to, and following that up with an anecdotal report on kids these days, from an email correspondent who teaches physics. Kevin’s emailer writes of his recent experiences with two different groups of… Continue reading Kids These Days: Is Our Learning Measure Valid?
Photons: Still Bosons
Last week, Dmitry Budker’s group at Berkeley published a paper in Physical Review Letters (also free on the arxiv) with the somewhat drab title “Spectroscopic Test of Bose-Einsten Statistics for Photons.” Honestly, I probably wouldn’t’ve noticed it, even though this is the sort of precision AMO test of physics that I love, had it not… Continue reading Photons: Still Bosons
Watching Individual Atoms Make a Phase Transition
A press release from Harvard caught my eye last week, announcing results from Markus Greiner’s group that were, according to the release, published in Science. The press release seems to have gotten the date wrong, though– the article didn’t appear in Science last week. It is, however, available on the arxiv, so you get the… Continue reading Watching Individual Atoms Make a Phase Transition
Dropping Bose Condensates for Fun and Science
An experiment in Germany has generated a good deal of publicity by dropping their Bose-Einstein Cendensate (BEC) apparatus from a 146 meter tower. This wasn’t an act of frustration by an enraged graduate student (anybody who has worked with BEC has probably fantasized about throwing at least part of their apparatus down a deep hole),… Continue reading Dropping Bose Condensates for Fun and Science
Table-Top X-Ray Lasers
I mentioned in a previous post that one of the cool talks I saw at DAMOP had to do with generation of coherent X-Ray beams using ultra-fast lasers. What’s particualrly cool about this work is that it doesn’t require gigantic accelerators or nuclear explosions to produce a laser-like beam of x-rays– it’s all done with… Continue reading Table-Top X-Ray Lasers
Relativity on a Human Scale
While I mostly restricted myself to watching invited talks at DAMOP last week, I did check out a few ten-minute talks, one of which ended up being just about the coolest thing I saw at the meeting. Specifically, the Friday afternoon talk on observing relativity with atomic clocks by Chin-Wen Chou of the Time and… Continue reading Relativity on a Human Scale