The most talked-about physics paper last week was probably Negative Absolute Temperature for Motional Degrees of Freedom (that link goes to the paywalled journal; there’s also a free arxiv preprint from which the above figure is taken). It’s a catchy but easily misinterpreted title– Negative absolute temperature! Below Absolute Zero! Thermodynamics is wrong!– that obscures… Continue reading What Does “Negative Temperature” Mean, Anyway?
Category: Atoms and Molecules
Using Light to Put a Mirror in the Dark: “Optomechanical Dark Mode”
In which I unpack a cryptic paper title and explain how quantum superposition lets you use light to keep things from interacting with light. ————- I joined AAAS a couple of years ago to get a break on the registration fee for their meeting, and I’ve kept up the membership mostly because I like having… Continue reading Using Light to Put a Mirror in the Dark: “Optomechanical Dark Mode”
Do the New Paper Dance
OK, it’s a paper I mentioned here before, when it went up on the arxiv, but the “Comments on Atomic, Molecular, and Optical Physics” article I wrote this summer is up on the Physica Scripta web site now, and for the next not-quite-thirty days it’s free to read and download: Searching for new physics through… Continue reading Do the New Paper Dance
What’s So Interesting About Single Quantum Systems? Physics Nobel 2012
In which we do a little imaginary Q&A to explain the significance of Tuesday’s Nobel Prize to Dave Wineland and Serge Haroche. ———— I did a quick post Tuesday morning noting that the latest Nobel Prize in Physics was awarded to two big names from my corner of the field. This would’ve been a great… Continue reading What’s So Interesting About Single Quantum Systems? Physics Nobel 2012
Congratulations to Dave Wineland, Serge Haroche, and KSC
The 2012 Nobel Prize in Physics was announced this morning, going to Serge Haroche and Dave Wineland, “for ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems”. This isn’t a pair that was getting much love from the prognosticators, but they’re an excellent choice. And, in fact, commenter KSC correctly picked Wineland… Continue reading Congratulations to Dave Wineland, Serge Haroche, and KSC
The “Ballistic” Story
Last week, in the post about fermion conduction, I left a reference hanging: There’s nothing physically blocking the atoms from flying right through the channel– in fact, an atom that enters the channel will always exit the other side without slowing down along the way. This is termed “ballistic,” a term that will always have… Continue reading The “Ballistic” Story
Simulating Wires with Atoms and Light: “Conduction of Ultracold Fermions Through a Mesoscopic Channel”
So, it’s been a while, but let’s see if we can’t hit the ground running with a good physics post. There have been a few notable physics events since I went on hiatus, but for a return to physics ResearchBlogging, we’ll go with something near and dear to my heart, ultracold atoms. Specifically, this Science… Continue reading Simulating Wires with Atoms and Light: “Conduction of Ultracold Fermions Through a Mesoscopic Channel”
The Towering Interferometer: “Testing General Relativity with Atom Interferometry”
In which we look at a slightly crazy-sounding proposal from my former boss, the experimental realization of which is getting close to completion. ———— I spent more or less the entire first day of DAMOP a couple of weeks ago going to precision measurement talks. Most of these were relatively sedate (at least by the… Continue reading The Towering Interferometer: “Testing General Relativity with Atom Interferometry”
Treating Big Molecules Like Electrons: “Real-time single-molecule imaging of quantum interference”
Richard Feyman famously once said that the double-slit experiment done with electrons contains everything that’s “‘at the heart of quantum physics.” It shows both particle and wave character very clearly: the individual electrons are detected one at a time, like particles, but the result of a huge number of detections clearly traces out an interference… Continue reading Treating Big Molecules Like Electrons: “Real-time single-molecule imaging of quantum interference”
On the Interconnectedness of Things
I finally got a copy of Cox and Forshaw’s The Quantum Universe, and a little time to read it, in hopes that it would shed some light on the great electron state controversy. I haven’t finished the book, but I got through the relevant chapter and, well, it doesn’t, really. That is, the discussion in… Continue reading On the Interconnectedness of Things