Nash inequality;
fractional powers of operators;
semigroup of operators;
logarithmic Sobolev inequality;
ultracontractivity property;
Dirichlet form;
D O I:
10.1090/S0002-9947-07-04020-2
中图分类号:
O1 [数学];
学科分类号:
0701 ;
070101 ;
摘要:
Assuming that a Nash type inequality is satisfied by a non-negative self-adjoint operator A, we prove a Nash type inequality for the fractional powers A(alpha) of A. Under some assumptions, we give ultracontractivity bounds for the semigroup (T-t,T-alpha) generated by -A(alpha).