Phase 2

  • quantum mechanics relative phase overall phase measurement probability
  • Quantum Fundamentals 2022 Consider the three quantum states: \[\left\vert \psi_1\right\rangle = \frac{4}{5}\left\vert +\right\rangle+ i\frac{3}{5} \left\vert -\right\rangle\] \[\left\vert \psi_2\right\rangle = \frac{4}{5}\left\vert +\right\rangle- i\frac{3}{5} \left\vert -\right\rangle\] \[\left\vert \psi_3\right\rangle = -\frac{4}{5}\left\vert +\right\rangle+ i\frac{3}{5} \left\vert -\right\rangle\]
    1. For each quantum state \(\left|{\psi_i}\right\rangle \) given above, calculate the probabilities of obtaining \(+\frac{\hbar}{2}\) and \(-\frac{\hbar}{2}\) when measuring the spin component along the \(x\)-, \(y\)-, and \(z\)-axes.
    2. Look For a Pattern (and Generalize): Use your results from \((a)\) to comment on the importance of the overall phase and of the relative phases of the quantum state vector.