Theory

Most of what would ordinarily be blogging time this morning got used up writing a response to a question at thePhysics Stack Exchange. But having put all that effort in over there, I might as well put it to use here, too... The question comes from a person who did a poster on terminology at the recently concluded American Geophysical Union meeting, offering the following definition of "data": Values collected as part of a scientific investigation; may be qualified as 'science data'. This includes uncalibrated values (raw data), derived values (calibrated data), and other transformations of…
Today is the official release date for the paperback edition of How to Teach Physics to Your Dog, so I wanted to write up something cool about quantum physics to mark the occasion. I looked around the house for inspiration, and most of what we have lying around the house is SteelyKid's toys. Thus, I will now explain the physics of quantum teleportation using SteelyKid's toys: "Wait, wait, wait... You're not seriously planning to explain something quantum without me, are you?" "I could hardly expect to get away with that, could I. No, I'm happy to have your contributions-- the book is about…
I hadn't heard anything about Dance of the Photons: From Einstein to Quantum Teleportation before it turned up in my mailbox, courtesy of some kind publicist at Farrar, Straus, and Giroux, otherwise I would've been eagerly anticipating it. Anton Zeilinger is a name to conjure with in quantum optics, having built an impressive career out of doing laboratory demonstrations of weird quantum phenomena. He shared the Wolf Prize earlier this year with John Clauser and Alain Aspect, and the three of them are in a small set of people who probably ought to get a Nobel at some point in the near future…
It's Thanksgiving here in the US, so blogging will be light to nonexistent. For the sake of those looking for a quick escape from the chaos of a family gathering, or, you know, those poor benighted souls in other countries for whom this is just another Thursday, here's a thematically appropriate poll about science: What are you most thankful for?online surveys Have a great holiday/ Thursday.
Regular commenter onymous left a comment to my review of Warped Passages that struck me as a little odd: The extended analogy between the renormalization group and a bureaucracy convinced me that she was trying way too hard to make sophisticated concepts comprehensible. Also, I'm not really sure that analogies are the best way to explain concepts to people without using mathematics. I'm not talking about the implication that making sophisticated concepts comprehensible is not worth doing, but rather the negativity toward analogies. It's odd because, if you think about it, a huge chunk of…
In a case of poor communication between publicists, I have ended up with not one but two advance copies of Massive by Ian Sample, a forthcoming book about the Higgs Boson. As I barely have time to read one, I don't remotely need two; thus, I will dispose of one with a really simple contest: I am thinking of an integer between 0 and 1000 (inclusive). The person who comes closest to guessing the number by midnight Eastern time Friday, November 5 wins a copy of Massive. Leave your guess in the comments. One entry per commenter, please. In the event that two or more people choose the same…
I have nothing useful or interesting to say about electoral politics, but I suspect that's all people will want to read about today. So here's a book post that's been backlogged for quite a while. Lisa Randall's Warped Passages: Unraveling the Mysteries of the Universe's Hidden Dimensions dates from 2005, and was, I think, part of the huge spate of string-theory-related books at that time (just before the String Theory Backlash books of 2006). It includes the usual survey of the Standard Model and the problems thereof, with an emphasis on the sort of extra-dimension theories that Randall and…
It's late October, which means that the thoughts of small children and adults who have never quite grown up turn to selecting appropriate costumes for Halloween. In the spirit of these literary suggestions and these abstract concept suggestions, I thought it would be useful to offer some suggestions for physics-themed costumes, for those who want to dress as something from the greatest science. Of course, there are some really obvious choices for physics-themed costumes (Einstein: rumpled clothes, white hair, distracted manner, German accent; Feynman: black pants, white shirt, brushed-back…
A big and important argument about religion and science has flared up again on Twittter. It occurs to me, though, that nobody has taken the obvious step of polling people about their actual beliefs, so let's see if we can't settle this question with (social) SCIENCE!: I would prefer to be a member of:Market Research What? It's not like this is any more pointless than the actual science-and-religion argument that's going on in blogdom.
Melissa at Confused at a Higher Level offers some thoughts on the relative status of experimental vs. theoretical science, spinning off a comprehensive discussion of the issues at Academic Jungle. I flagged this to comment on over the weekend, but then was too busy with SteelyKid and football to get to it. since I'm late to the party, I'll offer some slightly flippant arguments in favor of experiment or theory: Argument 1: Experimentalists are better homeowners. At least in my world of low-energy experimental physics, many of the skills you are expected to have as an experimental physicist…
Not long ago, a new preprint on the fine structure constant got a bunch of press, nicely summed up by the Knight Science Journalism Tracker last week. I meant to say something about this last week, but what with it being the first week of classes and all, I didn't find the time. I still think it's worth writing about, though, so after a reproduction of the key figure, we'll have the usual Q&A-format explanation of why I don't quite trust this result: So what's this all about? The preprint in question is the latest in a series of attempts to measure possible changes in the fine structure…
The theory of relativity takes its name from a very simple and appealing idea: that the laws of physics should look the same to moving observers as to stationary ones. "Laws of physics" here includes Maxwell's equations for electricity and magnetism, which necessarily means that moving observers must see the same speed of light as stationary observers (Einstein included the constancy of the speed of light as a second postulate in his original relativity paper, but it's redundant-- the constancy of the speed of light is a direct consequence of the principle of relativity). This leads directly…
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) an article from the Vermont Free Press about traffic cameras, a Toronto Star article citing the influence of YouTube on underground artists, and a blog article about the Phoenix Suns of the NBA. Incidentally, all of these articles also use the Uncertainty Principle incorrectly--by the…
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 is illustrated by the key to the lines shown at right. The category of physics is presented as "Theoretical Physics and Quantum Mechanics." I have no problem with the quantum part, as quantum mechanics is one of the greatest intellectual achievements in human history. I do have a problem…
I'm a big fan of review articles. For those not in academic science, "review article" means a long (tens of pages) paper collecting together the important results of some field of science, and presenting an overview of the whole thing. These vary somewhat in just how specific they are-- some deal with both experiment and theory, others just theoretical approaches-- and some are more readable than others, but typically, they're written in a way that somebody from outside the field can understand. These are a great boon to lazy authors, or authors facing tight page limits ("Ref. [1] and…
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 a limit on the maximum strength of a laser pulse due to quantum effects, specifically the creation of particle-antiparticle pairs. This is a little unusual, in that most of the time when people talk about really intense lasers, they end up discussing them as an oscillating…
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 seeing them lend their support to something that is just dripping with kook signifiers. The key paragraph of the overview of the theory is: To start grasping this higher-dimensional intuÂitive picÂture check out the book excerpts in the book excerpts secÂtion. If you are more…
So, last week, I talked about how superconductors work, and I have in the past talked about the idea of making cold atoms look like electrons. And obvious question, then, whould be: Do cold atoms systems allow us to learn anything about superconductivity? The answer here is, unfortunately, "Yes and no." That's pretty weaselly, dude. Yeah, well, there's nothing I can do about that. There are a huge number of experiments out there using ultracold atom systems to look at Bose Einstein Condensation, which is related to superconductivity, and that transition has been studied in great detail. Those…
On the reader request thread, commenter Brad had several questions; one led to yesterday's post about superconductors, another is a critical issue in pedagogy: Finally, why did all of my stat[istical] mech[anics] courses suck? Statistical Mechanics is the branch of physics that deals with building up macroscopic thermal properties of materials from a microscopic model of gas atoms with particular energy states. It's an important and powerful branch of physics dealing with things like the melting and freezing of various substances, and why entropy always increases, and things like that. It's…
I had the tab open and everything, and still somehow forgot to include a link to John Baez's blog post reporting on a talk by Tony Leggett which directly addresses some of the questions asked about yesterday's superconductivity post. It's about a talk called "Cuprate superconductivity: the current state of play" ("state of play" apparently being a favorite phrase of Leggett's), and directly addresses what's weird about high-temperature superconductors and why they haven't been explained theoretically. These are notes from a talk, and thus somewhat compressed, but it's a good summary of the…