Hi all,
See below for an interesting talk by Prof. Renner this week! Note that
registration is required.
Best,
-joe
---------- Forwarded message ---------
From: QSIT Seminar <qsit-seminar(a)phys.ethz.ch>
Date: Thu, Apr 23, 2020 at 5:31 PM
Subject: QSIT Seminar - Renato Renner - Thursday, April 30, 2020
To: <qsit-announce(a)phys.ethz.ch>, <iqe-faist(a)phys.ethz.ch>
Cc: Renato Renner <renner(a)ethz.ch>, Klaus Ensslin <ensslin(a)phys.ethz.ch>
Dear QSIT collaborators
The spirit of QSIT is based on interaction, collaboration and excellent
science. Since visiting each other is strongly limited these days, we
introduce an online QSIT seminar series. QSIT PIs will give zoom talks that
should be accessible to the general QSIT audience. The first QSIT seminar
will be given by Renato Renner, ETH Zurich, on "Quantum technology and the
ultimate limits of privacy". The talk will be on Thursday, April 30, 10 am.
Registration is required, see below.
We hope that you are healthy and continue to do science from home and are
looking forward to welcoming many of you for Renato’s talk next week.
Best regards,
Klara and Klaus
------------------------------------------------------------------------------------------------------
Date: Thursday, April 30, 2020
Time: 10:00
Place: scheduled Zoom meeting
Host: Klaus Ensslin
*Quantum technology and the ultimate limits of privacy*
*Renato Renner*
ETH Zurich
Abstract:
https://nccr-qsit.ethz.ch/news/talks-seminars/abstracts-2020/abstract-2020-…
*Please register for the QSIT Seminar using this link: *
https://ethz.zoom.us/meeting/register/tJYlc--oqjIvGtM71cPT00Kj2LOW4FQcaGZV
After registering, you will receive a confirmation email containing
information about joining the meeting.
*****
ETH Zurich
Klara Berg
NCCR QSIT Coordinator
Laboratory for Solid State Physics
HPF G 3.2
Otto-Stern-Weg 1
CH - 8093 Zurich
Phone: +41 44 633 38 44
kberg(a)phys.ethz.ch
www.nccr-qsit.ethz.ch
NCCR QSIT on Twitter <https://twitter.com/NCCR_QSIT>
Office: Mon, Tue, Thu, Fri
Hi all,
Tomorrow Mischa will tell us about some of his latest research,
specifically "General relativistic time dilation and increased uncertainty
in generic quantum clocks", which I believe is arxiv:1904.02178
<https://arxiv.org/abs/1904.02178>. The abstract is below. Zoom link:
https://ethz.zoom.us/j/362994444.
Best,
-joe
Abstract:
The theory of relativity associates a proper time with each moving object
via its world line. In quantum theory however, such well-defined
trajectories are forbidden. After introducing a general characterisation of
quantum clocks, we demonstrate that, in the weak-field, low-velocity limit,
all "good" quantum clocks experience time dilation as dictated by general
relativity when their state of motion is classical (i.e. Gaussian). For
nonclassical states of motion, on the other hand, we find that quantum
interference effects may give rise to a significant discrepancy between the
proper time and the time measured by the clock. We also show how ignorance
of the clock's state of motion leads to a larger uncertainty in the time
measured by the clock --- a consequence of entanglement between the clock
time and its center-of-mass degrees of freedom. We demonstrate how this
lost precision can be recovered by performing a measurement of the clock's
state of motion alongside its time reading.
Hi all,
Tomorrow Victor Gitton will tell us about a "Solvable Criterion for the
Contextuality of Any Prepare-and-Measure Scenario", his master thesis
research with Mischa. See below for the abstract. The zoom link is the
same: https://ethz.zoom.us/j/362994444
Best,
-joe
Abstract: Starting from arbitrary sets of quantum states and measurements,
referred to as the prepare-and-measure scenario, a generalized Spekkens
non-contextual ontological model representation of the quantum statistics
associated to the prepare-and-measure scenario is constructed. Any
prepare-and-measure scenario is either classical or non-classical depending
on whether it admits such a representation. A new mathematical criterion,
called unit separability, is formulated as the relevant classicality
criterion --- the name is inspired by the usual notion of quantum state
separability. Using this criterion, we first derive simple upper and lower
bounds on the cardinality of the ontic space. Then, we recast the unit
separability criterion as a possibly infinite set of linear constraints to
be verified, from which we derive two separate converging hierarchies of
algorithmic tests to witness non-classicality or certify classicality.
(Preprint: arXiv:2003.06426)
Hi all,
Tomorrow we'll have an external talk by Raffaele Salvia from Scuola Normale
Superiore di Pisa.
He'll tell us about "The statistics of work extraction"; see below for the
abstract.
The link to the meeting is https://ethz.zoom.us/j/362994444
Best,
-joe
Title: Statistics of work extraction
Abstract: Given a closed quantum system, the states we can reach with a
cyclic process are those in the same unitary orbit as the initial state.
The talk will begin with an outline of my proof that, under a very general
assumption on the Hamiltonian, the distribution of extractable work is a
gaussian with respect to the Haar measure. I shall then provide an
estimation of the additional work we can extract from multiple copies of
the system, as a function of the degree of correlation (MPO bond link rank)
allowed between the sites.