- 43

- 0

So does this mean that if the vector is at z=0 (pointing towards the equator), then it has neither spin-up nor spin-down components?

If the vector is pointing up 45 degrees above the equator towards |1>, then how is this represented by equations as a superposition of |1> and |0> ?

Also, if a qubit is not affected by external noise, then does it remain a static unprecessing vector on the Bloch Sphere?