Colloquium

Seminar information archive ~12/07Next seminarFuture seminars 12/08~

Organizer(s) ASUKE Taro, TERADA Itaru, HASEGAWA Ryu, MIYAMOTO Yasuhito (chair)
URL https://www.ms.u-tokyo.ac.jp/seminar/colloquium_e/index_e.html

2024/12/20

15:30-16:30   Room #大講義室 (Graduate School of Math. Sci. Bldg.)
Hideo Kozono (Waseda University / Tohoku University)
Helmholtz-Weyl decomposition and its application to the magnetohydrodynamic equations (日本語)
[ Abstract ]
We consider the Helmoltz-Weyl decomosition for $L^r$-vector fields in 3D bounded domains with the smooth boundary. The de Rham-Hodge-Kodaira decomposition of the $p$-form on compact Riemannian manifolds are well-known. However, in the general $L^r$-setting, such a decomposition has been relatively recently studied by
Fujiwara-Morimoto. In this talk, we deal with the 3D case and characterize two kinds of the space of harmonic vector fields in terms of the boundary condition where the vector fields are tangential or perpendicular to the boundary. Then it is clarified that the $L^r$-vector field is decomposed as a direct sum into harmonic, rotational and gradient parts. In particular, we bring the structure of the space with vector potentials into focus. As an application, we prove the asymptotic stability of the equilibrium to the magnetoydrodynamic equations associated with the harmonic vector field in the domain with the non-zero second Betti number. This is based on the joint work with Prof. Senjo Shimizu(Kyoto Univ.) and Prof. Taku Yanagisawa(Nara Women Univ.).
[ Reference URL ]
https://forms.gle/QNj3fohg3ZRMD8RHA