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This content will become publicly available on January 21, 2026

Title: Pushed and pulled fronts in a logistic Keller–Segel model with chemorepulsion *
Abstract We analyze spatial spreading in a population model with logistic growth and chemorepulsion. In a parameter range of short-range chemo-diffusion, we use geometric singular perturbation theory and functional-analytic farfield-core decompositions to identify spreading speeds with marginally stable front profiles. In particular, we identify a sharp boundary between between linearly determined, pulled propagation, and nonlinearly determined, pushed propagation, induced by the chemorepulsion. The results are motivated by recent work on singular limits in this regime using PDE methods (Grietteet al2023J. Funct. Anal.285110115).  more » « less
Award ID(s):
2205663
PAR ID:
10634060
Author(s) / Creator(s):
; ;
Publisher / Repository:
IOP
Date Published:
Journal Name:
Nonlinearity
Volume:
38
Issue:
2
ISSN:
0951-7715
Page Range / eLocation ID:
025017
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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