Effective dimension in subshifts

CUNY Logic WorkshopFriday, February 20, 20152:00 pmGC 6417

Linda Brown Westrick

Effective dimension in subshifts

University of Connecticut

A subshift is a subset of Cantor space that is both topologically closed and closed under the shift operation. Any element of a subshift can be viewed as a trajectory in a discrete dynamical system. One way a trajectory can be complicated is to have a large effective dimension. We consider the effective dimension spectrum of a subshift X, defined as { dim x : x ∈ X }, where dim is the effective dimension. Most commonly, the dimension spectrum of X is [ 0, h(X) ], where h(X) is the entropy of X. We give examples where the dimension spectrum does not follow this pattern, and discuss partial results and open questions related to the problem of characterizing the dimension spectra of subshifts. No prior knowledge about subshifts will be assumed.

Linda Brown Westrick received her doctorate in 2014 from the University of California at Berkeley, under the supervision of Ted Slaman. Currently she holds a postdoctoral position at the University of Connecticut. She works in computability theory and effective descriptive set theory, applying techniques from these areas to questions in analysis, symbolic dynamics, and chaos.

Posted by on January 12th, 2015