Title Information
Title
Multiple Timescales in the Fitzhugh-Nagumo Model
Type of Resource (primo)
dissertations
Name: Personal
Name Part
Bergland, Erik
Role
Role Term: Text
creator
Name: Personal
Name Part
Sandstede, Bjorn
Role
Role Term: Text
Advisor
Name: Personal
Name Part
Menon, Govind
Role
Role Term: Text
Reader
Name: Personal
Name Part
Carter, Paul
Role
Role Term: Text
Reader
Name: Corporate
Name Part
Brown University. Department of Applied Mathematics
Role
Role Term: Text
sponsor
Origin Information
Copyright Date
2024
Physical Description
Extent
13, 137 p.
digitalOrigin
born digital
Note: thesis
Thesis (Ph. D.)--Brown University, 2024
Genre (aat)
theses
Abstract
Abstract of Multiple Timescales in the Fitzhugh-Nagumo Model, by Erik Bergland, Ph.D., Brown University, October 2024. In addition to its importance to the field of biology, the Fitzhugh-Nagumo model of neuron activity is a well-established laboratory in the setting of multiple-timescale analysis. However, the model is often studied in a traveling-wave setting, in order to simplify the reaction-diffusion partial differential equations to a system of ordinary differential equations. In this work, we seek to understand whether solutions to the kinetic equations obtained by neglecting diffusion are attractors to the solutions of the full model in the case where initial data is nearly constant. Since these solutions are well understood via Fenichel theory and constant initial data implies that no diffusion occurs, we can obtain a useful picture of the behavior of the full model. We make use of pointwise estimates to establish boundedness of offsets from these solutions, or algebraic decay to the kinetic solutions when the initial data meets certain geometric constraints. A full analysis is possible while the solutions to the kinetic equations travel along fast jumps or near the locally invariant slow manifold. We also compute estimates of key quantities near points where normal hyperbolicity is lost and discuss their inadequacies for controlling the solutions to the PDE. In addition to the work on the Fitzhugh-Nagumo model, we also examine the behavior of weakly-coupled oscillators of Ginzburg-Landau type, where blowup analysis is crucial to proving the existence of snaking solutions.
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00893484")
Topic
Differential equations, Partial
Subject
Topic
Geometric Singular Perturbation Theory
Subject
Topic
Ordinary Differential Equations
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01012068")
Topic
Mathematical analysis
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20241015