On the potential operators associated with a semigroup
On the quadratic optimal control problem for Volterra integro-differential equations
On the range of a closed operator in an -space of vector-valued functions
Let be a reflexive Banach space and be a closed operator in an -space of -valued functions. Then we characterize the range of as follows. Let for all , where denotes the resolvent set of , and assume that and . Furthermore, assume that there exists such that . Then is equivalent to . This generalizes Shaw’s result for scalar-valued functions.
On the Range of the Generator of a Markovian Semigroup.
On the scattering theory for quantum dynamical semigroups
On the Schrödinger equation in L...spaces.
On the Schrödinger heat kernel in horn-shaped domains
We prove pointwise lower bounds for the heat kernel of Schrödinger semigroups on Euclidean domains under Dirichlet boundary conditions. The bounds take into account non-Gaussian corrections for the kernel due to the geometry of the domain. The results are applied to prove a general lower bound for the Schrödinger heat kernel in horn-shaped domains without assuming intrinsic ultracontractivity for the free heat semigroup.
On the semigroup of mappings on Fréchet Montel space
On the Semigroup of the Stokes Operator for Exterior Domains in Lq-Spaces.
On the semigroups of age-size dependent population dynamcis with spatial diffusion.
On the Sharpness of Non-Optimal Approximation for Semigroup Operators.
On the solutions of the inhomogeneous evolution equation in Banach spaces
Vengono dati nuovi teoremi di regolarità per le soluzioni dell'equazione nel caso in cui è il generatore infinitesimale di un semigruppo analitico in uno spazio di Banach e è una funzione continua.
On the Spectra of Certain Semi-Groups.
On the spectral bound of the generator of a -semigroup
We give several conditions implying that the spectral bound of the generator of a -semigroup is negative. Applications to stability theory are considered.
On the spectral properties of translation operators in one-dimensional tubes
We study the spectral properties of some group of unitary operators in the Hilbert space of square Lebesgue integrable holomorphic functions on a one-dimensional tube (see formula (1)). Applying the Genchev transform ([2], [5]) we prove that this group has continuous simple spectrum (Theorem 4) and that the projection-valued measure for this group has a very explicit form (Theorem 5).
On the spectrum of a one-parameter strongly continous representation.
On the spectrum of the analytic generator.
On the stability of differentiability of semigroups.
On the stability of nonlinear Feynman-Kac semigroups
On the stability of strongly continuous semigroups of positive operators on