Things I’ve written

These are in roughly increasing order of technical difficulty.

  • Quite a few years ago, I wrote some answers to frequently asked questions about black holes. (The sections that describe astronomical observations of black holes are a few years out of date, but the theory of black holes hasn’t changed recently, so the theoretical parts are still current.)
  • Bayesian inference is the quantitative way of describing how a person’s opinions about a scientific (or in principle any other) issue get updated when new data come in. I wrote a description of how Bayesian inference works in a particular example, specifically how my opinion of the density of the Universe changed in the light of some new data.
  • Creationists sometimes argue that biological evolution is impossible, because it is contradicted by the Second Law of Thermodynamics.  This is nonsense, of course.  I published an article explaining why in the American Journal of Physics.  (This article uses intermediate undergraduate-level physics.)
  • Cosmology books often describe the expanding Universe using the metaphor of a stretching rubber sheet.  David Hogg and I think that this analogy often does more harm than good.  Here’s why. (Also published in A.J.P.  This journal is pretty much the only place to go for articles at the boundary between physics research and pedagogical explanation.)
  • How does the electric field get out of a black hole? This question was posed a while back in the Q&A section of the American Journal of Physics. Matt McIrvin and I wrote a brief answer that was published in the journal. You can view our answer in either HTML or PostScript format.
  • John Baez and I wrote an explanation of the meaning of Einstein’s field equation. This is one of the most important equations in physics, but it’s generally thought to be too difficult for anyone but specialists to understand. We show how to state the equation without too much daunting mathematics.  (A.J.P. yet again!)
  • I gave a series of lectures at a NATO Advanced Study Institute on the cosmic microwave background radiation.
  • You can get my Ph.D. thesis in either gzipped PostScript or PDF format.
  • In addition to the above, I’ve written a bunch of journal articles, most of which are available for download on the incredibly useful preprint arXiv.