Alexandria Digital Research Library

Redundant Information and the Quantum-Classical Transition

Author:
Riedel, Charles Jess
Degree Grantor:
University of California, Santa Barbara. Physics
Degree Supervisor:
Mark Srednicki
Place of Publication:
[Santa Barbara, Calif.]
Publisher:
University of California, Santa Barbara
Creation Date:
2012
Issued Date:
2012
Topics:
Physics, General, Information Science, and Physics, Quantum
Keywords:
Redundant Information
Decoherence
Quantum Mechanics
Quantum-Classical Transition
Quantum Information
Genres:
Online resources and Dissertations, Academic
Dissertation:
Ph.D.--University of California, Santa Barbara, 2012
Description:

A state selected at random from the Hilbert space of a many-body system is overwhelmingly likely to exhibit highly non-classical correlations. For these typical states, half of the environment must be measured by an observer to determine the state of a given subsystem. The objectivity of classical reality---the fact that multiple observers can each agree on the state of a subsystem after measuring just a small fraction of its environment---implies that the correlations found in nature between macroscopic systems and their environments are very exceptional. This is understood through the redundant recording of information about the preferred states of a decohering system by its environment, a phenomenon known as quantum Darwinism. To see this in action in the real world, we first consider the ubiquitous case of blackbody illumination. We show that it exhibits fast and extensive proliferation of information about an object into the environment, yielding redundancies orders of magnitude larger than the exactly soluble models considered previously. Turning to a universe of qubits, we examine the conditions needed for the creation of branching states and study their demise through many-body interactions. We show that even constrained dynamics can suppress redundancies to the values typical of random states on relaxation timescales, and prove that these results hold exactly in the thermodynamic limit. Finally, we connect these ideas to the consistent histories framework. Building on the criterion of partial-trace consistency, we introduce a sensible notion of mutual information between a fragment of the universe and a history itself.

Physical Description:
1 online resource (135 pages)
Format:
Text
Collection(s):
UCSB electronic theses and dissertations
ARK:
ark:/48907/f3mc8x0c
ISBN:
9781267768223
Catalog System Number:
990039148030203776
Rights:
Inc.icon only.dark In Copyright
Copyright Holder:
Charles Riedel
Access: This item is restricted to on-campus access only. Please check our FAQs or contact UCSB Library staff if you need additional assistance.