談話会 YORDANOV, Borislav「On the Global Behavior of Solutions to a Non-autonomous Nonlinear Wave Equation in 3D」、TORIELLI, Michele 「Sectional matrices and geometrical consequences of their extremal behaviour」

開催日時
2016年   7月 27日 15時 00分 ~   17時 30分
場所
北海道大学理学部4号館501号室
講演者
YORDANOV, Borislav、TORIELLI, Michele
 
15:00--16:00 YORDANOV, Borislav
16:00--16:30 お茶会
16:30--17:30 TORIELLI, Michele
18:30-- 懇親会

YORDANOV, Borislav
タイトル:On the Global Behavior of Solutions to a Non-autonomous Nonlinear Wave Equation in 3D
アブストラクト:We study the 3D wave equation with a non-autonomous nonlinearity which is effective only on a given space-time surface (line). Such equations are closely related to the equations arising in equivariant wave maps. For some non-characteristic surfaces (lines), we establish the global existence of unbounded solutions in the energy space using the Hardy inequality. We also show the finite time blow up of solutions when the nonlinearity is effective on a characteristic surface and the initial data are non-negative.

TORIELLI, Michele
タイトル:Sectional matrices and geometrical consequences of their extremal behaviour
アブストラクト:In this talk I will recall the definition of the sectional matrix of an homogenous ideal as given by Bigatti and Robbiano. I will describe the main properties of the sectional matrix and give some geometrical consequences of this properties, especially in the case of ideals of points in projective space. This is part of a work in progress with Bigatti and Palezzato.


関連項目

研究集会・セミナー・集中講義の一覧へ