Bubbles and droplets in a singular limit of the FitzHugh–Nagumo system
Interfaces and free boundaries, Tome 20 (2018) no. 2, pp. 165-210

Voir la notice de l'article provenant de la source EMS Press

DOI

The FitzHugh–Nagumo system gives rise to a geometric variational problem, when its parameters take values in a particular range. A stationary set of the variational problem satisfies an Euler–Lagrange equation that involves the curvature of the boundary of the set and a nonlocal term that inhibits unlimited growth and spreading. The nonlocal term is the solution of a nonhomogeneous modified Helmholtz equation with the characteristic function of the stationary set as the inhomogeneous term. Two types of stationary sets are studied: disc shaped stationary sets in the plane, termed bubbles, and unions of perturbed small discs, termed droplet assemblies, in bounded domains. A complete description of the existence and the stability of bubbles is established. Depending on the parameters, there may be zero, one, two, or even three bubbles. Droplet assemblies are constructed by a reduction argument. Each droplet in a stationary assembly is close in size and shape to the corresponding bubble in the plane. The locations of the droplets in the assembly are determined by the Green’s function of the modified Helmholtz equation.
DOI : 10.4171/ifb/400
Classification : 49-XX, 33-XX, 35-XX, 92-XX
Mots-clés : FitzHugh–Nagumo system, standing pulse, singular limit, nonlocal geometric variational problem, bubbles, droplet assemblies

Chao-Nien Chen  1   ; Yung-Sze Choi  2   ; Xiaofeng Ren  3

1 National Tsing Hua University, Hsinchu, Taiwan
2 University of Connecticut, Storrs, USA
3 George Washington University, Washington, USA
Chao-Nien Chen; Yung-Sze Choi; Xiaofeng Ren. Bubbles and droplets in a singular limit of the FitzHugh–Nagumo system. Interfaces and free boundaries, Tome 20 (2018) no. 2, pp. 165-210. doi: 10.4171/ifb/400
@article{10_4171_ifb_400,
     author = {Chao-Nien Chen and Yung-Sze Choi and Xiaofeng Ren},
     title = {Bubbles and droplets in a singular limit of the {FitzHugh{\textendash}Nagumo} system},
     journal = {Interfaces and free boundaries},
     pages = {165--210},
     year = {2018},
     volume = {20},
     number = {2},
     doi = {10.4171/ifb/400},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ifb/400/}
}
TY  - JOUR
AU  - Chao-Nien Chen
AU  - Yung-Sze Choi
AU  - Xiaofeng Ren
TI  - Bubbles and droplets in a singular limit of the FitzHugh–Nagumo system
JO  - Interfaces and free boundaries
PY  - 2018
SP  - 165
EP  - 210
VL  - 20
IS  - 2
UR  - http://geodesic.mathdoc.fr/articles/10.4171/ifb/400/
DO  - 10.4171/ifb/400
ID  - 10_4171_ifb_400
ER  - 
%0 Journal Article
%A Chao-Nien Chen
%A Yung-Sze Choi
%A Xiaofeng Ren
%T Bubbles and droplets in a singular limit of the FitzHugh–Nagumo system
%J Interfaces and free boundaries
%D 2018
%P 165-210
%V 20
%N 2
%U http://geodesic.mathdoc.fr/articles/10.4171/ifb/400/
%R 10.4171/ifb/400
%F 10_4171_ifb_400

Cité par Sources :