The AIP’s Physics News Update this week highlights a paper on the laser cooling and trapping of radium by a group at Argonne National Laboratory. This is a new record for the heaviest atom ever cooled and trapped. It’s not quite as cool as the previous record, which involved the trapping of francium atoms that… Continue reading Trapping Radium
Category: Physics
Quantum Gravity: Physics?
The post title is taken from the announcement for today’s colloquium talk. The abstract: Quantum gravity is the theory which is thought to underlie quantum theory and general relativity. I will introduce the subject, emphasizing recent results which suggest that spatial geometry is discrete. Such discrete geometry may have an observational signature, especially if it… Continue reading Quantum Gravity: Physics?
Thought Experiments Made Real
We’re back from Boskone, which included lots of fun stuff, and not enough sleep. I also cleverly forgot to bring my lecture notes home from work, which means I need to go in early to figure out what the hell I’m talking about in class today, so there’s not much time for blogging at the… Continue reading Thought Experiments Made Real
New Limits on Constancy
There’s a press release on EurekAlert about new measurements limiting the change in the fine structure constant from the Time and Frequency division of NIST in Boulder: Some astronomical and geological studies suggest there might have been very small changes in the values of fundamental constants over billions of years, although the results have been… Continue reading New Limits on Constancy
Not All That Much of a Paradox, Really
In general, EuerkAlert has been a useful source for drawing my attention to interesting things that I might not otherwise notice. Every now and then, though, there are press releases that just make me faintly embarrassed for everyone involved. Such as yesterday’s announcement from LSU: Subhash Kak, Delaune Distinguished Professor of Electrical and Computer Engineering… Continue reading Not All That Much of a Paradox, Really
Dorky Poll: Favorite Calculational Shortcut
I’m giving an exam at 9:00 this morning– neither snow, nor more snow, nor blowing snow, nor single-digit temperatures shall stay the progress of shaping young minds. Anyway, to keep things lively while I’m proctoring the test, here’s a poll question inspired by the exam: What’s your favorite calculational shortcut? Today’s test is on basic… Continue reading Dorky Poll: Favorite Calculational Shortcut
Want to Be a Doctor? Major in Physics
Somebody at work had printed out a table of MCAT scores by major, compiled by the AIP. I couldn’t find it on the web, but I found the original source, and made my own version of the relevant bit. This shows the average numerical scores on the three sections of the MCAT test for students… Continue reading Want to Be a Doctor? Major in Physics
Modern Experimental Physics Update
Over at metadatta, Sujit is doing spectroscopy experiments with interferometers, and has posted a very nice introduction to the technique. Basically, if you have a light source emitting two different wavelengths that are very close together, you can determine the wavelength difference by shinging the light into an interferometer, and seeing how far you need… Continue reading Modern Experimental Physics Update
New Particles and Epicycles
PhysicsWeb has a story about a new theory of axions that claims to resolve some discrepancies between past experiments. Two previous experiments looking for axions– hypothetical weakly interacting particles that might be an explanation for dark matter– have found conflicting results: the CAST experiment looking for axions produced in the Sun found nothing, while the… Continue reading New Particles and Epicycles
Scientist Cleared, Process Unclear
The New York Times reports that Purdue has officially cleared Rusi Taleyarkhan of charges of scientific wrongdoing over his claim to have produced nuclear fusion on a tabletop through the magic of sonoluminescence. You might recall that these claims were made a couple of years ago, but nobody else has been able to replicate them.… Continue reading Scientist Cleared, Process Unclear