Daily Archives: February 17, 2010

Tinker, Tailor …

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Tale of a Would-Be Spy, Buried Treasure, and Uncrackable Code

When officials searched the aspiring spy, they found a paper tucked under the insole of his right shoe. On it were written the addresses of several Iraqi and Chinese embassies in Europe. In a trouser pocket they discovered a spiral pad in which Regan, who had been trained in cryptanalysis by the Air Force, had written 13 seemingly unconnected words — like tricycle, rocket, and glove. Another 26 words were written on an index card. In his wallet was a paper with a string of several dozen letters and numbers beginning “5-6-N-V-O-A- I …” And in a folder Regan had been carrying, they found four pages filled with three-digit numbers, or trinomes: 952, 832, 041, and so on. The spiral pad, the index card, the wallet note, and the sheets of trinomes: The FBI suddenly had four puzzles to solve.

Stop! In the Name of Physics

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In Brookhaven Collider, Scientists Briefly Break a Law of Nature

The departure from normal physics manifested itself in the apparent ability of the briefly freed quarks to tell right from left. That breaks one of the fundamental laws of nature, known as parity, which requires that the laws of physics remain unchanged if we view nature in a mirror.

Ok, that’s interesting — that the reaction violated parity conservation, which I imagine has implications for the matter/antimatter asymmetry issue (I have long wondered if symmetry violation conditions changed with energy, and now it appears that they can and do). But if a reaction violates parity conservation, then parity conservation is not a law of nature; at best you have a “parity conservation zone.” Laws of nature describe how nature behaves. Whatever nature does, it is in accordance with these laws.

The editor who came up with the title needs to write “It is impossible to violate the laws of nature” a thousand times.

For more on the science, and confirmation that this follows, rather than breaks, the laws of physics, check out Cosmic Variance

Update: for some backstory on parity violation, check out Symmetry: It’s More Like a Guideline about the confirmation of how weak interactions don’t “keep to the code.”

Don't Sign Them, Though

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Let’s draw Feynman diagams!

So we see that the external lines correspond to incoming or outgoing particles. What about the internal lines? These represent virtual particles that are never directly observed. They are created quantum mechanically and disappear quantum mechanically, serving only the purpose of allowing a given set of interactions to occur to allow the incoming particles to turn into the outgoing particles. We’ll have a lot to say about these guys in future posts.