Abstract
Alinhac solved a long-standing open problem in 2001 and established that quasilinear wave equations in two space dimensions with quadratic null nonlinearities admit global-in-time solutions,provided that the initial data are compactly supported and sufficiently small in Sobolev norm.In this work,Alinhac obtained an upper bound with polynomial growth in time for the top-order energy of the solutions.A natural question then arises whether the time-growth is a true phenomenon,despite the possible conservation of basic energy.In the present paper,we establish that the top-order energy of the solutions in Alinhac theorem remains globally bounded in time.
基金项目
中国博士后科学基金(2021M690702)
国家自然科学基金(11725102)
Sino-German Center(M-0548)
国家重点研发计划(2018AAA0100303)
National Support Program for Young Top-Notch Talents()
上海市科技计划(21JC1400600)
上海市科技计划(19JC1420101)