Symmetry of numerical range and semigroup generation of in nite dimensional Hamiltonian operators

Symmetry of numerical range and semigroup generation of in nite dimensional Hamiltonian operators

This paper deals with the in nite dimensional Hamiltonian operator with unbounded entries. Using the core of its entries, we obtain the conditions under which the numerical range of such an operator is symmetric with respect to the imaginary axis. Based on the symmetry above, a necessary and sufficient condition for generating C 0 semigroups is further given.

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