« search calendars« Rutgers Discrete Mathematics Seminar

« Entropy and Letter Density for Shifts of Finite Type

Entropy and Letter Density for Shifts of Finite Type

April 17, 2023, 2:00 PM - 3:00 PM

Location:

Conference Room 705

Rutgers University

Hill Center

110 Frelinghuysen Rd

Piscataway, NJ 08854

Jacob Richey, University of British Columbia

Given an iid binary string conditioned to not have 1001 as a substring, how many 1s and 0s does it typically have? More generally, given a finite set of 'forbidden' patterns over a finite alphabet, we can study the associated shift of finite type, i.e. all strings avoiding the forbidden set. Which forbidden sets are the most/least restrictive, and which give a higher/lower density of 1s? I will present old and new results, and many unanswered questions. Combinatorics, probability, and symbolic dynamics will each play a role.