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Alexandr
Nov2-09, 09:42 PM
Guys,

I'm stuck with a simple and stupid question...

We have a spin "up" and "down" as a qubit 1 and 0 states.
Now can we consider a state perpendicular to this basis direction as a (0+1)/sqrt(2) state?

If not then what is the sence of the phase shift x in the state (0+exp(ix)1)/sqrt(2)?

DrChinese
Nov3-09, 11:09 AM
Guys,

I'm stuck with a simple and stupid question...

We have a spin "up" and "down" as a qubit 1 and 0 states.
Now can we consider a state perpendicular to this basis direction as a (0+1)/sqrt(2) state?

If not then what is the sence of the phase shift x in the state (0+exp(ix)1)/sqrt(2)?

An electron has spin components in the x, y and z directions where x, y and z are mutually perpendicular. These components do not commute, so knowledge of one does not represent knowledge of another.

A photon is different, as the perpendicular component is directly related.