PIRSA:12110068 Scientific Series

DOI10.48660/12110068

Series: Quantum Foundations

Pusey, M. (2012). What's an unknown POVM, and what does a two qubit state look like?. Perimeter Institute. https://pirsa.org/12110068

Pusey, Matthew. What's an unknown POVM, and what does a two qubit state look like?. Perimeter Institute, Nov. 06, 2012, https://pirsa.org/12110068 

@misc{ pirsa_PIRSA:12110068,
  doi = {10.48660/12110068},
  url = {https://pirsa.org/12110068},
  author = {Pusey, Matthew},
  keywords = {},
  language = {en},
  title = {What{\textquoteright}s an unknown POVM, and what does a two qubit state look like?},
  publisher = {Perimeter Institute},
  year = {2012},
  month = {nov},
  note = {PIRSA:12110068 see, \url{https://pirsa.org}}
}

Abstract

If probabilities represent knowledge, what is an "unknown
probability"? De Finetti's theorem licenses the view that it is simply a
convenient metaphor for a certain class of knowledge about a series of
events. There are quantum versions for "unknown states" and "unknown
channels". I will explain how "unknown measurements" can be rehabilitated
too.

I will then move to a totally different topic. The Bloch sphere is handy
for representing qubit states, but the equivalent for two qubits is
15-dimensional! I will advocate instead drawing the set of states that Bob
can steer Alice to, the "steering ellipsoid". I will show how entanglement
and discord look from this perspective, and outline a geometric
classification of separable two qubit states.

Resources

Next talk