# The field of definition of the iterates of a rational function

Seminar

Speaker

Dr. Solomon Vishkautsan (Tel-Hai Academic College)

Date

13/03/2019 - 11:30 - 10:30Add to Calendar

`2019-03-13 10:30:00``2019-03-13 11:30:00``The field of definition of the iterates of a rational function``We will discuss the field of definition of a rational function and in what ways it can change under iteration, in particular when the degree over the base field drops. We present two families of rational functions with the property above, and prove that in the special case of polynomials, only one of these families is possible. We also explain how this relates to Ritt's decomposition theorem on polynomials. Joint work with Francesco Veneziano (SNS Pisa).``Third floor seminar room (room 201, building 216)``אוניברסיטת בר-אילן - Department of Mathematics``mathoffice@math.biu.ac.il``Asia/Jerusalem``public`Place

Third floor seminar room (room 201, building 216)

Abstract

We will discuss the field of definition of a rational function and in what ways it can change under iteration, in particular when the degree over the base field drops. We present two families of rational functions with the property above, and prove that in the special case of polynomials, only one of these families is possible. We also explain how this relates to Ritt's decomposition theorem on polynomials. Joint work with Francesco Veneziano (SNS Pisa).

Last Updated Date : 26/01/2019