All Questions
3 questions
2
votes
1
answer
151
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What are non-standard ways to describe the distance between states?
I understand that when comparing two arbitrary quantum states, one may use various measures to encapsulate the difference between states such as trace distance, fidelity or relative quantum entropy. I ...
- 39
2
votes
1
answer
315
views
What is the quantum relative entropy between pure states?
Given two pure quantum state $\rho=|\psi_\rho\rangle\langle\psi_\rho\mid$ and $\sigma=\mid\psi_\sigma\rangle\langle\psi_\sigma\mid$ ($\rho\neq\sigma$).
We know that the fidelity between quantum ...
- 103
5
votes
1
answer
179
views
Is the quantum min-relative entropy $D_{\min}(\rho\|\sigma)=-\log(F(\rho, \sigma)^2)$ or $D_{\min}(\rho\|\sigma)=-\log(tr(\Pi_\rho\sigma))$?
In John Watrous' lectures, he defines the quantum min-relative entropy as
$$D_{\min}(\rho\|\sigma) = -\log(F(\rho, \sigma)^2),$$
where $F(\rho,\sigma) = tr(\sqrt{\rho\sigma})$. Here, I use this ...
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