Sharp regularity of gradient blow-up solutions in the Camassa-Holm equation

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Kim, Yunjoo, Kwon, Bongsuk, Yoon, Jeongsik
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909410513649664
author Kim, Yunjoo
Kwon, Bongsuk
Yoon, Jeongsik
author_facet Kim, Yunjoo
Kwon, Bongsuk
Yoon, Jeongsik
contents We study the formation of singularities in the Camassa-Holm (CH) equation, providing a detailed description of the blow-up dynamics and identifying the precise Hölder regularity of the gradient blow-up solutions. To this end, we first construct self-similar blow-up profiles and examine their properties, including the asymptotic behavior at infinity, which determines the type of singularity. Using these profiles as a reference and employing modulation theory, we establish global pointwise estimates for the blow-up solutions in self-similar variables, thereby demonstrating the stability of the self-similar profiles we construct. Our results indicate that the solutions, evolving from smooth initial data within a fairly general open set, form $C^{3/5}$ cusps as the first singularity in finite time. These singularities are analogous to \emph{pre-shocks} emerging in the Burgers equation, exhibiting unbounded gradients while the solutions themselves remain bounded. However, the nature of the singularity differs from that of the Burgers equation, which is a cubic-root singularity, i.e., $C^{1/3}$. Our work provides the first proof that generic pre-shocks of the CH equation exhibit $C^{3/5}$ Hölder regularity. It is our construction of new self-similar profiles, incorporating the precise leading-order correction to the CH equation in the blow-up regime, that enables us to identify the sharp Hölder regularity of the singularities and to capture the detailed spatial and temporal dynamics of the blow-up. We also show that the generic singularities developed in the Hunter-Saxton (HS) equation are of the same type as those in the CH equation.
format Preprint
id arxiv_https___arxiv_org_abs_2412_00558
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Sharp regularity of gradient blow-up solutions in the Camassa-Holm equation
Kim, Yunjoo
Kwon, Bongsuk
Yoon, Jeongsik
Analysis of PDEs
35Q35, 35A21, 76B15, 35C06, 76B25
We study the formation of singularities in the Camassa-Holm (CH) equation, providing a detailed description of the blow-up dynamics and identifying the precise Hölder regularity of the gradient blow-up solutions. To this end, we first construct self-similar blow-up profiles and examine their properties, including the asymptotic behavior at infinity, which determines the type of singularity. Using these profiles as a reference and employing modulation theory, we establish global pointwise estimates for the blow-up solutions in self-similar variables, thereby demonstrating the stability of the self-similar profiles we construct. Our results indicate that the solutions, evolving from smooth initial data within a fairly general open set, form $C^{3/5}$ cusps as the first singularity in finite time. These singularities are analogous to \emph{pre-shocks} emerging in the Burgers equation, exhibiting unbounded gradients while the solutions themselves remain bounded. However, the nature of the singularity differs from that of the Burgers equation, which is a cubic-root singularity, i.e., $C^{1/3}$. Our work provides the first proof that generic pre-shocks of the CH equation exhibit $C^{3/5}$ Hölder regularity. It is our construction of new self-similar profiles, incorporating the precise leading-order correction to the CH equation in the blow-up regime, that enables us to identify the sharp Hölder regularity of the singularities and to capture the detailed spatial and temporal dynamics of the blow-up. We also show that the generic singularities developed in the Hunter-Saxton (HS) equation are of the same type as those in the CH equation.
title Sharp regularity of gradient blow-up solutions in the Camassa-Holm equation
topic Analysis of PDEs
35Q35, 35A21, 76B15, 35C06, 76B25
url https://arxiv.org/abs/2412.00558