English

Solutions with single radial interface of the generalized Cahn-Hilliard flow

Analysis of PDEs 2022-09-30 v1

Abstract

We consider the generalized parabolic Cahn-Hilliard equation ut=Δ[ΔuW(u)]+W(u)[ΔuW(u)](t,x)R~×Rn, u_t=-\Delta\left[\Delta u -W'(u)\right]+W''(u)\left[\Delta u -W'(u)\right] \qquad \forall\, (t, x)\in \widetilde{{\mathbb R}}\times{\mathbb R}^n, where n=2n=2 or n4n\geq 4, W()W(\cdot) is the typical double-well potential function and R~\widetilde{\mathbb R} is given by R~={(0,),\mboxifn=2,(,0),\mboxifn4. \widetilde{\mathbb R}=\left\{ \begin{array}{rl} (0, \infty), &\quad \mbox{if } n=2, (-\infty, 0), & \quad\mbox{if } n\geq 4. \end{array} \right. We construct a radial solution u(t,x)u(t, x) possessing an interface. At main order this solution consists of a traveling copy of the steady state ω(x)\omega(|x|), which satisfies ω(y)W(ω(y))=0\omega''(y)-W'(\omega(y))=0. Its interface is resemble at main order copy of the sphere of the following form x=2(n3)(n1)2t4,(t,x)R~×Rn, |x|=\sqrt[4]{-2(n-3)(n-1)^2t}, \qquad \forall\, (t, x)\in \widetilde{{\mathbb R}}\times{\mathbb R}^n, which is a solution to the Willmore flow in Differential Geometry. When n=1n=1 or 33, the result consists trivial solutions.

Cite

@article{arxiv.2209.14522,
  title  = {Solutions with single radial interface of the generalized Cahn-Hilliard flow},
  author = {Chao Liu and Jun Yang},
  journal= {arXiv preprint arXiv:2209.14522},
  year   = {2022}
}
R2 v1 2026-06-28T02:20:26.325Z