Reconfiguring List Colorings

Series
Time
Tuesday, March 7, 2023 - 3:45pm for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Daniel Cranston – Virginia Commonwealth University – dcranston@vcu.eduhttps://www.people.vcu.edu/~dcranston/
Organizer
Tom Kelly

A \emph{list assignment} L gives to each vertex v in a graph G a
list L(v) of
allowable colors.  An \emph{L-coloring} is a proper coloring φ such that
φ(v)L(v) for all vV(G).  An \emph{L-recoloring move} transforms
one L-coloring to another by changing the color of a single vertex.  An
\emph{L-recoloring sequence} is a sequence of L-recoloring moves.  We study
the problem of which hypotheses on G and L imply that for that every pair
φ1 and φ2 of L-colorings of G there exists an L-recoloring
sequence that transforms φ1 into φ2.  Further, we study bounds on
the length of a shortest such L-recoloring sequence.

We will begin with a survey of recoloring and list recoloring problems (no prior
background is assumed) and end with some recent results and compelling
conjectures.  This is joint work with Stijn Cambie and Wouter Cames van
Batenburg.