2009/03/31 by A. F. M. ter Elst, Derek W. Robinson, ter Elst, A. F. M. +3
Computer Science · Mathematics · #Advanced Mathematical Modeling in Engineering #Nonlinear Partial Differential Equations #Spectral Theory in Mathematical Physics #math.AP #msc:35J70
paper · pdf · doi:10.48550/arxiv.0903.5482
arxiv created 2009/03/31 · arxiv updated 2009/12/01
Let S be the submarkovian semigroup on L2(\bf Rd) generated by a self-adjoint, second-order, divergence-form, elliptic operator H with W1,∞ coefficients ckl. Further let Ω be an open subset of \bf Rd. Under mild conditions we prove that S leaves L2(Ω) invariant if, and only if, it is invariant under the flows generated by the vector fields ∑l=1d ckl ∂l for all k.