"Decoherence and Beyond"

by

Robin J. Blume-Kohout

B.A. (Kenyon College) 1998
M.A. (University of California, Berkeley) 2000

A dissertation submitted in partial satisfaction of the
requirements for the degree of
Doctor of Philosophy
in
Physics

in the

GRADUATE DIVISION
of the
UNIVERSITY OF CALIFORNIA, BERKELEY

Spring (March 28) 2005

Abstract:  I investigate the ways in which information, about an open quantum system, is recorded in its environment.  The underlying themes are classicality and its symptom, objectivity.  How decoherence leads to redundantly recorded information is of particular importance.  Redundancy is introduced as a concrete manifestation of objectivity, and a set of tools for identifying redundancy is presented.  Several variants of spin bath and oscillator bath models for decoherence are analyzed in terms of redundancy.  Redundant information storage is shown to be a common feature of decoherence models.

   Predictability and amplification, two related symptoms of classicality, are also explored.  I introduce the operator sieve, an improved algorithm for implementing the predictability sieve, and apply it to the problem of connecting redundancy and predictability.  This leads to a general theory of information-preserving structures, which unifies pointer bases with decoherence-free subspaces/subsystems in an algebraic framework.  As a first step in exploring amplification (and its connections with redundancy), a simple analytic model of an unstable environment is solved.  I show that a single amplifying degree of freedom can produce more (and faster) decoherence than an bath of infinitely many oscillators.

Important Information:

My dissertation is quite long.  It contains quite a bit of information, including approximately 75 color figures.  The ~389 422 pages[*] of manuscript include:
For the convenience of readers, and in order to minimize the number of trees that need to die, I have provided several two versions of the same text below.  Please be aware that generating all these versions is somewhat time-consuming.  The ones labeled "*not available yet*" are ones that I haven't yet generated.  Please request one of these by email (robin AT blumekohout DOT com ) if you actually need it, and I'll be glad to generate it.  If possible, I will provide the following abstractions:
  1. UC - Official version (double spaced, 12 pt)
  2. A more efficient, single-spaced version
  3. Color pages only.  I assume that you will print double-sided, so this includes all page-pairs for which one side or the other is color.
  4. Non-color pages only.  See previous line for explanation -- this consists of all the other pages.  The idea is that you can print this one on a B&W printer, the other on a color printer, and interleave them.

[*] The University of California requires that all dissertations be double spaced (really, truly, double spaced, not space-and-a-half).  The recommended font size is 12 point.  This inflates the size of a document quite a bit.  The single-spaced version -- formatted a little less tightly than a typical Phys. Rev. paper -- is about 253 pages long.  Printing this version will save one or two trees.

Current revision: March 28, 2005
Postscript (gzipped)
Adobe PDF
Official (double-spaced, 12 pt, ~422 pages)
thesis.dsp.ps.gz
thesis.dsp.pdf
Color page-pairs only (double-spaced, 12 pt, ~136 pages) *not available any more* *not available yet*
B&W page-pairs only (double-spaced, 12 pt, ~253 pages) *not available any more* *not available yet*
Efficient (single-spaced, 10 pt, ~253 pages) thesis.ssp.ps.gz thesis.ssp.pdf
Color page-pairs only (single-spaced, 10 pt, ~111 pages) *not available any more* *not available yet*
B&W page-pairs only (single-spaced, 10 pt, ~123 pages) *not available any more* *not available yet*



1st revision: January 26, 2005
Postscript (gzipped)
Adobe PDF
Official (double-spaced, 12 pt, ~389 pages)
thesis.dsp.ps.gz
thesis.dsp.pdf
Color page-pairs only (double-spaced, 12 pt, ~136 pages) colorthesis.dsp.ps.gz *not available yet*
B&W page-pairs only (double-spaced, 12 pt, ~253 pages) bwthesis.dsp.ps.gz *not available yet*
Efficient (single-spaced, 10 pt, ~234 pages) thesis.ssp.ps.gz thesis.ssp.pdf
Color page-pairs only (single-spaced, 10 pt, ~111 pages) colorthesis.ssp.ps.gz *not available yet*
B&W page-pairs only (single-spaced, 10 pt, ~123 pages) bwthesis.ssp.ps.gz *not available yet*