Hi all,
Johannes Bausch from Cambridge will give this week's QIT Seminar, which
will take place Thursday morning at 11am. He'll tell us about "Complexity,
Quantum Information and Quantum Algorithms"; see below for the abstract.
Usual zoom channel: https://ethz.zoom.us/j/362994444
Best,
Joe
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Abstract: Loosely speaking, complexity theory is the study of how hard or
easy it is to answer certain computational problems. I will be presenting
three areas of quantum theory in this context. First I will focus on the
study of error correction codes in the communication context, utilizing
novel computational techniques such as neural network quantum states and
graph states to push known noise thresholds beyond the state-of-the-art.
The next topic will be on many-body systems, utilizing spectral techniques
to prove that various macroscopic properties such as ground state energies,
spectral gaps, or phase diagrams can be hard to compute, or even
undecidable. Finally, I will focus on the algorithmic side of quantum
computation, and present our recent work on improving quantum simulation of
the Fermi Hubbard model, and recurrent (quantum) neural networks.
Hi all,
Tomorrow Jinzhao will tell us about "The refined quantum extremal surface
prescription from the asymptotic equipartition property". See below for the
abstract. Usual time and place: 2pm https://ethz.zoom.us/j/362994444.
Best,
Joe
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The quantum extremal surface prescription, born out of the Ryu Takayanagi
formula in AdS/CFT, is a general rule of computing entanglement entropy in
gravity. Its usefulness is highlighted in the recent black hole Page curve
calculation. In this talk I will introduce the recent refinement of the
QES prescription, showing the significance of the smooth conditional
min/max-entropies. Inspired by the asymptotic equipartition property, I
will sketch a path integral derivation of it in the context of holography
with a novel replica trick. In the end, I will show that the derivation
implies the correction also applies beyond AdS/CFT and in particular to the
Page curve.
Hi all,
Tomorrow Michał Bączyk will tell us about his master's thesis on "Black
Hole Holographic Models in the framework of Gaussian Quantum Information",
supervised partly by Mischa. See below for the abstract. We'll start at 2pm
on zoom: https://ethz.zoom.us/j/362994444.
Best,
Joe
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Title: Black Hole Holographic Models in the framework of Gaussian Quantum
Information
Abstract:
In this work, we make the first step towards introducing the operational
quantum information notions into the framework of Conformal Field Theories
and AdS/CFT correspondence. We provide an original toolkit for
investigating the action of Bosonic Gaussian channels on the QFTs
incorporated into the language of Gaussian Quantum Information.
Specifically, we study the quench protocol dynamics for the case of vacuum
state of 1D harmonic chain system and the TFD state. These are Gaussian
states that have meaningful dual descriptions in the language of AdS/CFT
correspondence. To evaluate the character of the free and interrupted by
channels evolution we calculate numerically for the systems of interest
quantum entropies and fidelities all using recent advances in the Gaussian
Quantum Information.