Built on Facts

Effective today, this site has moved! The good folks at ScienceBlogs asked me if I’d be interested in writing at their site. I was, so I am. Don’t worry, everything will stay exactly the same with the sole exception of the new address. The full story is at the new location. [...]

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Tom Hudson was a retired small-town engineer, an avid remote control aircraft hobbyist, and a good friend. When I was a young person living in Slidell between 1989 and 2001, he and his wife Lucy were my family’s next door neighbor. Our families became very close, and in a way they were like [...]

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This weekend we’ll add a little statistics to our ongoing Sunday tour of the zoo of mathematical functions!

This is the Poisson distribution for λ = 4. To be formally correct, it’s only defined for integer values. This pops up in physics all the time in the context of counting discrete events with independent [...]

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This is the graph of the Bessel function of order 0, along with its asymptotic approximation for large x. You can see that the convergence is quite fast. The Bessel function is important in many problems in physics, from solutions of the Helmholtz equation in cylindrical coordinates (as in a vibrating drumhead) to [...]

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For some light weekend posting, here’s the latest xkcd. It’s a pretty funny commentary on the state of academic discourse in literary fields. Remember the Sokal affair? That’s what happens when you build a discipline on something other than facts.
Which is too bad. Literature and its study are beautiful things, but [...]

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Well. I had planned to write the story of my weekend in Atlanta watching a wedding, but a whopping six hour delay at the Hartsfield-Jackson Atlanta International Airport meant I didn’t get back home in time to write up much here to make the Monday morning post. With any luck I should have [...]

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Here’s a final scheduled post before I get back home later today. Spammers haven’t overrun my comments, I trust? Either way, consider this an open post to discuss whatever you wish if you’d like!
Until tomorrow, let’s contemplate the probability density for the Schroedinger solution of a bouncing ball in a fairly low excited [...]

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Physics is intimately bound up with probability and statistics for two main reasons. First, both thermodynamics and quantum mechanics are intrinsically probabilistic theories. So are some others, but those two in particular really embody the statistical concepts central to modern physics. Second, much of experimental physics is done at the bleeding edge [...]

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I propose an experiment. Head on over to Cosmic Variance or Bad Astronomy. Count the posts on the front page that have to do with their respective subject areas and how many have to do with politics or religion. Hold that ratio in your head for a moment.
Professor Orzel on Uncertain Principles [...]

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Grab a hydrogen atom, hit it with a photon of the appropriate energy, and bump it up to its first excited state. After a while it will spontaneously release a photon and resume its quiescence in the ground state. Simple enough, and the general idea of atoms absorbing and spontaneously releasing photons is [...]

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