Quantum Darwinism: Amplification and the Acquisition of Information by Spin Environments

Zwolak, Michael P.¹  Riedel, Jess²  Zurek, Wojciech H.³ 

[1] Oregon State Univ., Corvallis, OR (United States) Dept. of Physics;IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center;Los Alamos National Lab. (LANL), Los Alamos, NM (Unite

关键词: ATOMIC AND NUCLEAR PHYSICS;   

DOI  :  10.2172/1136936
RP-ID  :  LA-UR-14-25093
PID  :  OSTI ID: 1136936

学科分类：物理（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

Quantum Darwinism recognizes the role of the environment as a communication channel: Decoherence can amplify select information ??? information about the pointer states of a system of interest (preventing access to complementary information about superpositions of those states). We examine the amplification process for a spin environment under a variety of conditions. For initially pure environment states, the contribution to decoherence and the partial record deposited in an environment spin are both determined by the overlap of conditional states generated on the spin. For mixed environments, however, decoherence and a partial record are no longer directly related. The partial record, though, is given by a generalized measure of overlap ??? the quantum Chernoff information. The latter quantity is a measure of distinguishability and gives the efficiency of the amplification process. We calculate the Chernoff information and show explicitly that, except for a set of measure zero, there is always redundant information acquired by the environment.