Homework 8 exercise 2 probabilities

Homework 8 exercise 2 probabilities

par Daniel Andrzej Polka,
Nombre de réponses : 1

Hi,

I'm not quite sure how to compute the probabilities of the different outcomes for the global shared state. I successfully computed all four possible outcomes, but I don't know what formula/method I should use to compute the probability that a certain outcome should arise in this exercise. Could someone point me to some class notes or explain it to me please? Thanks in advance.

En réponse à Daniel Andrzej Polka

Re: Homework 8 exercise 2 probabilities

par Nicolas Macris,

Hi,

If you computed the four possible outcomes, you have computed the projection P |psi> where

P is the appropriate projector and |psi> the initial state.

The probability of this outcome is then <psi| P |psi>.

Note that since P^2=P for a projector this is also equal to <psi| P^2|psi> and so it suffices to compute the norm of P|psi>.

Hope this clarifies