Hi all,
this Wednesday we have Adrian Hutter from ETH Zurich speaking at 4pm
in the Time room. His title and abstract are below.
Best wishes,
Markus
Title: A Quantum Information Approach to Statistical Physics
Abstract: I will first present a theorem based on the Decoupling
Theorem of [1] which gives sufficient and necessary conditions for a
quantum channel (CPTPM) being such that it yields the same output
for almost all possible inputs. This theorem allows us to reproduce
and generalize results of [2,3], in which cornerstones of
statistical physics are derived from first principles of quantum
mechanics, in a very natural and easy way. Specifically, we express
them in a way which allows to apply results about random 2-qubit
interactions [4]. Furthermore, we apply this theorem to provide a
criterion for whether different initial states of some subspace of a
quantum mechanical system in contact with an environment have at
some given time already evolved to the same state or not. As it
turns out, this question can be answered by examining a simple
entropic inequality evaluated for just one particular state [5].
Applying this criterion to realistic Hamiltonians with local
interactions may lead to improved bounds on the thermalization times
of quantum mechanical systems. Joint work with Stephanie Wehner.
[1] F. Dupuis, M. Berta, J. Wullschleger, and R. Renner,
arXiv:1012.6044v1 (2010).
[2] S. Popescu, A. Short, and A. Winter, Nature Physics 2, 754
(2006).
[3] N. Linden, S. Popescu, A. Short, and A. Winter, New Journal of
Physics 12, 055021 (2010).
[4] A. Harrow and R. Low, Communications in Mathematical Physics
291, 257 (2009).
[5] A. Hutter and S. Wehner, arXiv:1111.3080v3 (2011).