Last summer, there was a fair bit of hype about a paper from Mark Raizen’s group at Texas which was mostly reported with an “Einstein proven wrong” slant, probably due to this press release. While it is technically true that they measured something Einstein said would be impossible to measure, that framing is a little… Continue reading Proving Einstein Wrong…ish: Measurement of the Instantaneous Velocity of a Brownian Particle
Category: Thermo/StatMech
Treating Photons Like Atoms: “Bose-Einstein condensation of photons in an optical microcavity”
This paper made a big splash back in November, with lots of news stories talking about it; it even made the #6 spot on Physics World‘s list of breakthroughs of the year. I didn’t write it up then because I was hellishly busy, and couldn’t take time away from working on the book-in-progress to figure… Continue reading Treating Photons Like Atoms: “Bose-Einstein condensation of photons in an optical microcavity”
Photons and Atoms Approaching Equilibrium
The latest snowstorm is wreaking some havoc on my plans for the day, which means I’m going to lift another question and answer from the Physics Stack Exchange, with some modification. This one is a question about thermal radiation: What are the quantum mechanisms behind the emission and absorption of thermal radiation at and below… Continue reading Photons and Atoms Approaching Equilibrium
Winter Poll: “Bitter” Cold
A seasonally appropriate poll, brought to you by this morning’s frigid dog walk (15F/ -9C), and the memory of a newscast back when I was in Maryland that referred to an overnight low temperature of 22F/-6C as “Bitter, bitter cold”: The maximum (daytime high) temperature I would characterize as “bitter cold” would be:survey software For… Continue reading Winter Poll: “Bitter” Cold
Who Is the Velvet Underground of Science?
I’m shamelessly stealing this question from James Nicoll, who asked it about science fiction. The question is a play on the famous comment that only of order a thousand people bought the first Velvet Underground record, but every one of them went on to start a band. So, the question is, who is the Velvet… Continue reading Who Is the Velvet Underground of Science?
Melting Simulated Insulators
The Joerg Heber post that provided one of the two papers for yesterday’s Hanbury Brown Twiss-travaganza also included a write-up of a new paper in Nature on Mott insulators, which was also written up in Physics World. Most of the experimental details are quite similar to a paper by Markus Greiner’s group I wrote up… Continue reading Melting Simulated Insulators
Wind and Temperature: Why Doesn’t Windy Equal Hot?
I got forwarded a physics question last night asking about the connection between wind and temperature, which I’ll paraphrase as: Temperature is related to the motion of the atoms and molecules making a substance up, with faster motion corresponding to higher temperature. So why does it feel warmer when the air is still and why… Continue reading Wind and Temperature: Why Doesn’t Windy Equal Hot?