Feynman Lectures, Chapter I: The Most Important Idea in Science

Back to the Feynman lectures! The writing is quite beautiful — Feynman is very clear and readable, while still packing a great deal of information into a small space. There’s no way one blog post of reasonable length could cover all of the ground that Feynman does in each chapter. And this chapter is especially densely packed, because this chapter is setup. After some brief introductory remarks — and some philosophical comments on the nature of science that I’ll get to in a later post — Feynman gives the class a killer hook, and then uses that hook to reel the students (and readers) in through a quick introduction to many, many concepts that will come up again later in the text….

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Blogging the Feynman Lectures

I’m trying something new here, starting with this post: I’m blogging the Feynman Lectures on Physics, chapter-by-chapter (approximately). For those of you unfamiliar with the Feynman Lectures, they’re a classic set of introductory college physics lectures given by the great Richard Feynman 50 years ago at Caltech, compiled into book form. But despite their provenance, the books are not really introductory. They’re more like a rite of passage…

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Entropy and Billy Pilgrim

The Second Law of Thermodynamicsentropy never decreases in a closed system — is among the more famous laws of physics. If you’re reading this blog, I’d be surprised if you’ve never heard of entropy before. You’ve probably also heard that entropy has something to do with disorder, and that the Second Law basically says that the universe tends toward disorder, but that’s not quite what the second law says — entropy isn’t really the same thing as disorder, though they’re related.

So what’s entropy? To answer that, I’ll steal a little bit from Kurt Vonnegut

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Epistolary Higgs

Over the summer, the big physics news was the discovery of a new particle which is, in all likelihood, the Higgs boson. I’m not going to give a detailed explanation of what the Higgs is and how it was found — Bruce Bassett wrote a great post about that here, there’s a more detailed post here, and a set of more detailed posts here.

Instead, here’s an e-mail exchange I had with a friend about the Higgs — he had a question, and I answered it, but there’s a bit more to it than that…

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Postcard from the Edge

This is a picture taken by a robot over one-and-a-half million kilometers away from the earth — over three times farther away than the moon — of the oldest light in the universe. This is impossibly faint light: it took a full year for the robot to collect enough light to take this picture. And even if it weren’t so faint, we wouldn’t be able to see this light with our eyes because it’s beyond the range of visible light, stretched by the expansion of the universe over the last 14 billion years…

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Neutrinos and Flux Capacitors

Apparently, a team of scientists working at CERN have found evidence suggesting that neutrinos can travel faster than the speed of light. While this has turned a few heads, the wide consensus is that this will probably turn out to be some kind of systematic error and not a real effect. Extraordinary claims require extraordinary evidence, and this evidence has to pass a hell of a lot more tests — and be reproduced by a lot more people — before anyone, including the team who produced the results, will feel comfortable saying that they’ve found a way around the ultimate speed limit. But why would this be such an extraordinary claim? The speed of light is a hard limit in Einstein’s relativity, but why?…

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