connecting 1945-era “nsa” cryptanalysis to quantum mechanics and modern laser-based cryptanalysis.

Back to Turing’s crypto model, expressed by physics



lecture 11, bala

When discussing the coherent states of light (in a lecture that comes on the heels of her discussion of the compressed quantum-only state) her argument starts out, Turing like, asking about the expected value of a+.a – whose mean is 1. She shows the ket and then the bra form of the eigenvector equations, and then puts the two back to back indicating that the amplitudes can be a representation of a wheels probability distribution.

In physics terms HOWEVER, the value is the intensity of the light.

Remember the discussion of the WWII-era NSA 5205 cryptanalyzer, that used a light intensity detector to do counting superpositions of depths.

Now project that forward to world in which lasers are being used (rather than light bulges and photodiodes… No longer are folks layering lots of hollywood film together (and running through the light projected at high-speed, with an

Remember GCCS considered building this device but it never happened, since


About home_pw

Computer Programmer who often does network administration with focus on security servers. Sometimes plays at slot machine programming.
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