The Physics Bus

SteelyKid, like most toddlers, knows a few songs, and likes to sing them over and over. Her repertoire is limited to “ABCDEFG” (the alphabet song, but that’s how she requests it), “Twinkle, Twinkle,” “Some man” (“This Old Man,” which I only figured out this weekend), and “Round and Round” (“The Wheels on the Bus”). I […]

What Every Dog Should Know About Quantum Physics

A quick check-in from Tuscaloosa, where we’re getting ready to head out for the football tailgating. While I’ve got a minute, though, here are the slides from my public lecture, via SlideShare: What Every Dog Should Know About Quantum Physics View more presentations from Chad Orzel. These are probably less comprehensible that some of my […]

What Uncertainty Means to Me– And You, and the Universe

In chapter 2 of How to Teach Physics to Your Dog, there’s a footnote about the ubiquity of uncertainty principle analogies in the mass media: To give you an idea of the breadth of subjects in which this shows up, in June 2008, Google turned up citations of the Heisenberg Uncertainty Principle in (among others) […]

Without Experiment, There Is No Theory

A lot of people have been blogging and Twittering about this subway map of science, which puts various branches of science in the place of the lines on the London Underground map, showing connections between them. It’s a huge graphic, but a kind of cool image. I do, however, have a problem with it, which […]

Indirect Excitation Control: Ultrafast Quantum Gates for Single Atomic Qubits

Last week, John Baez posted a report on a seminar by Dzimitry Matsukevich on ion trap quantum information issues. In the middle of this, he writes: Once our molecular ions are cold, how can we get them into specific desired states? Use a mode locked pulsed laser to drive stimulated Raman transitions. Huh? As far […]

Quantum Optics from the Opposite Direction: QED Limits on Laser Intensities

Most of the time, when we talk about seeing quantum effects from light, we talk about extremely weak beams– looking at intensities where one photon more or less represents a significant change in the intensity of the light. Last week, though, Physics Buzz wrote up a paper that goes in the other direction: they suggest […]

Technology, Entertainment, and Quantum Kookiness

A reader emails to ask about a new-to-me theory of physics, called “Quantum Space Theory” being promoted by a fellow named Thad Roberts. I wouldn’t usually bother with this, but Roberts was one of the speakers at TEDx Boulder. this is disappointing, to put it mildly– TED is a respected organization, and I don’t like […]

All the Myriad Inceptions

In comments to yesterday’s post about my favorite Many-Worlds story, a couple of people mention “All the Myriad Ways,” a Larry Niven short story. I don’t think I’ve ever actually read the story, but it gets brought up all the time, so I’m familiar with the concept. It’s an angle on Many-Worlds that I don’t […]

Many-Worlds in Fiction: “Divided by Infinity”

Today, has posted the complete story “Divided by Infinity” by Robert Charles Wilson. This remains probably the best science fiction story ever using the Many-Worlds interpretation of quantum physics (though it doesn’t call it that explicitly), and also the creepiest: In the year after Lorraine’s death I contemplated suicide six times. Contemplated it seriously, […]

What’s a Photon, and How Do We Know they Exist?

A reader emailed me with a few questions regarding How to Teach Physics to Your Dog, one of which is too good not to turn into a blog post: What is a photon from an experimental perspective?… Could you perhaps provide me with a reference that discusses some experiments and these definitional issues? The short […]