Past exam of the mathematics course of the University of Cambridge / 2020 / ii / Paper 1 / 10C / v

Table of contents
- Solution v

Solution

The Born rule says that the probability of a projective-measurement outcome is the squared norm of the state projected onto the corresponding eigenspace. The basis vectors in the state whose second qubit is one are

∣010 ⟩, ∣110 ⟩, ∣111 ⟩ .

They are mutually orthogonal, so

P (second qubit = 1) = ∣ b ∣^{2} + ∣ c ∣^{2} + ∣ d ∣^{2} .

 Ancestors (10)

 View article source

 Discussion (0)

There are no discussions about this article yet.

 Articles by others on the same topic (0)

There are currently no matching articles.

  See all articles in the same topic Create my own version