Title Information
Title
Confluence in Chip-Firing and Related Combinatorial Processes
Type of Resource (primo)
dissertations
Name: Personal
Name Part
Liscio, Patrick Hirsch
Role
Role Term: Text
creator
Name: Personal
Name Part
Klivans, Caroline
Role
Role Term: Text
Advisor
Name: Personal
Name Part
Guzman, Johnny
Role
Role Term: Text
Reader
Name: Personal
Name Part
Chan, Melody
Role
Role Term: Text
Reader
Name: Corporate
Name Part
Brown University. Department of Applied Mathematics
Role
Role Term: Text
sponsor
Origin Information
Copyright Date
2022
Physical Description
Extent
xxii, 229 p.
digitalOrigin
born digital
Note: thesis
Thesis (Ph. D.)--Brown University, 2022
Genre (aat)
theses
Abstract
Confluence is an important property in many combinatorial processes. A globally confluent process is one in which a fixed initial state always leads to a fixed final state, even if different choices of moves are made throughout the process. In many processes, including chip-firing, global confluence is proven using local confluence: if two moves are available at the same time, they may be performed in either order. We consider processes that exhibit global confluence without local confluence. We begin with labeled chip-firing, a modified chip-firing process in which chips with numerical labels are fired according to certain rules. Under some conditions, the chips are guaranteed to end the process in sorted order. We provide a new proof that labeled chip-firing from an initial configuration with $2m$ chips at the origin always leads to a sorted final configuration. The proof involves analyzing a poset of firing moves, which contains a diamond of locally confluent moves at the end of the process. We use similar methods to prove confluence in related processes, including other initial configurations, variations of the line graph, and classical root system types. We also analyze the class of move posets. We show that locally confluent diamonds are generated in move posets on a much larger class of bipartite graphs. We also show that the move poset is isomorphic to the poest of join-irreducible chip configurations. We prove this by introducing edge colorings, called $S$-colorings, of lower locally distributive lattices. We show that $S$-colorings describe moves in many other combinatorial processes, and we use $S$-colorings to provide a new proof of a theorem stating that all shortest paths between flip-connected domino tilings use the same flip moves in a possibly different order.
Subject
Topic
Combinatorics
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01400410")
Topic
Applied mathematics
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20220706