Re: Quantum Cryptography can not work

extrasense@xxxxxxxxxxx wrote:
Let us say we have considerable intensity of coherrent light, created
by a laser.
Do you claim, that its polarization can not be measured?

Measuring the polarization of a photon forces it into a
definite state (eigenstate). Then you can measure at a
different angle and get a value for that polarization,
and it will be *different* from what you get if you
hadn't performed the first measurement. Further, the
coherence between two split beams is *destroyed* when
the measurement is made, which is the basic principle
that enables quantum cryptography. This is all basic
quantum physics, well understood by the physics
community and well demonstrated by numerous experiments.
.

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