Monotonicity of the Quantum Relative Entropy Under Positive Maps

verfasst von
Alexander Müller-Hermes, David Reeb
Abstract

We prove that the quantum relative entropy decreases monotonically under the application of any positive trace-preserving linear map, for underlying separable Hilbert spaces. This answers in the affirmative a natural question that has been open for a long time, as monotonicity had previously only been shown to hold under additional assumptions, such as complete positivity or Schwarz-positivity of the adjoint map. The first step in our proof is to show monotonicity of the sandwiched Renyi divergences under positive trace-preserving maps, extending a proof of the data processing inequality by Beigi (J Math Phys 54:122202, 2013) that is based on complex interpolation techniques. Our result calls into question several measures of non-Markovianity that have been proposed, as these would assess all positive trace-preserving time evolutions as Markovian.

Organisationseinheit(en)
Institut für Theoretische Physik
SFB 1227: Designte Quantenzustände der Materie (DQ-mat)
Externe Organisation(en)
Københavns Universitet
Typ
Artikel
Journal
Annales Henri Poincare
Band
18
Seiten
1777-1788
Anzahl der Seiten
12
ISSN
1424-0637
Publikationsdatum
01.05.2017
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Statistische und nichtlineare Physik, Kern- und Hochenergiephysik, Mathematische Physik
Elektronische Version(en)
https://doi.org/10.1007/s00023-017-0550-9 (Zugang: Geschlossen)