Program
Full Program | Thursday | Friday | Saturday | All Sessions | Posters | Talks
LSU SQuInT Event Map
SESSION 6: Quantum information theory I (Theatre)Chair: (Itay Hen (Southern California)) | |
8:30am - 9:15am | Fernando Brandao, IQIM, Caltech Quantum Gibbs sampling | Abstract. Quantum thermal states, aka Gibbs states, are fundamental objects in physics. I will discuss recent results on the role of Gibbs states on quantum information theory. First I will show how we can use them to give quantum speed-ups for semidefinite programming. Then I will discuss how to prepare Gibbs states efficiently on a quantum computer. |
9:15am - 9:45am | Dawei Ding, Stanford Conditional mutual information of bipartite unitaries and scrambling | Abstract. One way to diagnose chaos in bipartite unitary channels is via the tripartite information of the corresponding Choi state, which for certain choices of the subsystems reduces to the negative conditional mutual information (CMI). We study this quantity from a quantum information-theoretic perspective to clarify its role in diagnosing scrambling. When the CMI is zero, we find that the channel has a special normal form consisting of local channels between individual inputs and outputs. However, we find that arbitrarily low CMI does not imply arbitrary proximity to a channel of this form, although it does imply a type of approximate recoverability of one of the inputs. When the CMI is maximal, we find that the residual channel from an individual input to an individual output is completely depolarizing when the other input is maximally mixed. However, we again find that this result is not robust. We also extend some of these results to the multipartite case and to the case of Haar-random pure input states. Finally, we look at the relationship between tripartite information and its Renyi-2 version which is directly related to out-of-time-order correlation functions. In particular, we demonstrate an arbitrarily large gap between the two quantities. |
SQuInT Chief Organizer
Akimasa Miyake, Assistant Professor
amiyake@unm.edu
SQuInT Co-Organizer
Mark M. Wilde, Assistant Professor LSU
mwilde@phys.lsu.edu
SQuInT Administrator
Gloria Cordova
gjcordo1@unm.edu
505 277-1850
SQuInT Event Coordinator
Karen Jones, LSU
kjones@cct.lsu.edu
SQuInT Founder
Ivan Deutsch, Regents' Professor
ideutsch@unm.edu