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 […]

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 […]

The Limits of Rohirrim Vision

Over at Tor.com, Kate has a Lord of the Rings re-read post about the Battle of the Pelennor Fields, which includes a shout-out to me that I missed because I was driving to NYC: Éomer is “scarely a mile” away when the standard unfurls and is clearly seen to bear the White Tree, Seven Stars, […]

The Most Amazing Laser Application of All Time Is…

Voting has closed on the Laser Smackdown poll, with 772 people recording their opinion on the most amazing of the many things that have been done with lasers in the fifty years since the invention of the first working laser (see the Laserfest web site for more on the history and applications of lasers). The […]

Laser Smackdown: Final Days of Voting for the Most Amazing Laser Application

We’re just over 600 votes in the Laser Smackdown poll in honor of the 50th anniversary of the laser, as of early Friday morning. I notice that it has moved off the front page of the blog, though, so here’s another signal-boosting repost, just so we have as many votes as possible, to establish maximum […]

Reminder: Vote for the Most Amazing Laser Application of All Time

As of 1:45 Monday, 217 people have cast votes in the Laser Smackdown poll. That’s not bad, but it’s currently being handily beaten by the 271 people who have voted for a favorite system of units. The nice thing about using actual poll services for this sort of thing, though, is that I can re-post […]

Amazing Laser Application 12: Laser Guide Stars!

What’s the application? Producing artificial “stars” to serve as a reference for telescopes using adaptive optics to correct for atmospheric turbulence. This allows ground-based telescopes to produce images that are as good as those from the Hubble Space Telescope. What problem(s) is it the solution to? “How can I make this giant telescope produce even […]

Amazing Laser Application 11: Frequency Combs!

What’s the application? An optical frequency comb is a short-duration pulsed laser whose output can be viewed as a regularly spaced series of different frequencies. If the pulses are short enough, this can span the entire visible spectrum, giving a “comb” of colored lines on a traditional spectrometer. This can be used for a wide […]

Amazing Laser Application 10: Surgery!

What’s the application? Using lasers to cut and/or cauterize tissue during surgical procedures, instead of the traditional very small very sharp knives. What problem(s) is it the solution to? 1) “How can we do surgery without touching the tissues being operated on?” 2) “How can I get rid of these annoying glasses/contact lenses?” How does […]

Amazing Laser Application 8: Holography!

What’s the application? Holograms are images of objects that appear three-dimensional– if you move your head as you look at a hologram, you will see the usual parallax effects, unlike a normal photograph, which is fixed. So, if your hologram includes one object that is partly behind another object, you can see around the obstruction […]