W czwartek 19.10.2023 r. o godzinie 11:15 w sali A.1.14 w budynku C19 zostanie wygłoszony wykład w ramach działalności Centrum Rylla-Nardzewskiego.
Speaker: Tomasz Downarowicz
Title: Topological normality preservation by addition
Abstract:
In this lecture, inaugural for the CRN seminar, I will present something perhaps interesting, very natural and - above all - easy to follow, namely, an answer to the question given below: A symbolic sequence x over a finite alphabet A= {0,1,2,...,r-1} is called topologically normal if it is transitive in the full shift over A (that is, every finite block of symbols occurs in x). In the shift space we introduce coordinatewise addition modulo r.
In this lecture, inaugural for the CRN seminar, I will present something perhaps interesting, very natural and - above all - easy to follow, namely, an answer to the question given below: A symbolic sequence x over a finite alphabet A= {0,1,2,...,r-1} is called topologically normal if it is transitive in the full shift over A (that is, every finite block of symbols occurs in x). In the shift space we introduce coordinatewise addition modulo r.
Question:
What sequences y over A have the property that x + y is topologically normal for every topologically normal sequence x?
The answer is surprising, because it involves a new class of sequences that presumably none of us has ever heard about before.