On the Range of the Generator of a Markovian Semigroup.
On the stability of nonlinear Feynman-Kac semigroups
On the transient and recurrent parts of a quantum Markov semigroup
We define the transient and recurrent parts of a quantum Markov semigroup 𝓣 on a von Neumann algebra 𝓐 and we show that, when 𝓐 is σ-finite, we can write 𝓣 as the sum of such semigroups. Moreover, if 𝓣 is the countable direct sum of irreducible semigroups each with a unique faithful normal invariant state ρₙ, we find conditions under which any normal invariant state is a convex combination of ρₙ's.
On two quantum versions of the detailed balance condition
Quantum detailed balance conditions are often formulated as relationships between the generator of a quantum Markov semigroup and the generator of a dual semigroup with respect to a certain scalar product defined by an invariant state. In this paper we survey some results describing the structure of norm continuous quantum Markov semigroups on ℬ(h) satisfying a quantum detailed balance condition when the duality is defined by means of pre-scalar products on ℬ(h) of the form (s ∈ [0,1]) in order...
On uniformly smoothing stochastic operators
We show that a stochastic operator acting on the Banach lattice of all -integrable functions on is quasi-compact if and only if it is uniformly smoothing (see the definition below).
Perturbation des résolvantes et des semi-groupes par une mesure de Radon positive.
Poincaré inequalities and hitting times
Equivalence of the spectral gap, exponential integrability of hitting times and Lyapunov conditions is well known. We give here the correspondence (with quantitative results) for reversible diffusion processes. As a consequence, we generalize results of Bobkov in the one dimensional case on the value of the Poincaré constant for log-concave measures to superlinear potentials. Finally, we study various functional inequalities under different hitting times integrability conditions (polynomial,…)....
Poincaré inequality for some measures in Hilbert spaces and application to spectral gap for transition semigroups
Potential-theoretical methods in the construction of measure-valued Markov branching processes
We develop potential-theoretical methods in the construction of measure-valued branching processes.We complete results of P. J. Fitzsimmons and E. B. Dynkin on the construction, regularity and other properties of the superprocess associated with a given right process and a branching mechanism.
Precise estimates on the rate at which certain diffusions tend to equilibrium.
Propriétés d'invariance du domaine du générateur infinitésimal étendu d'un processus de Markov
Pseudo differential operators with negative definite symbols of variable order.
One way to represent the generator of a Markov process is given by pseudo differential operators. Above all this is due to the fact that the generator satisfies the so-called positive maximum principle (...).
Quantum detailed balance conditions with time reversal: the finite-dimensional case
We classify generators of quantum Markov semigroups on (h), with h finite-dimensional and with a faithful normal invariant state ρ satisfying the standard quantum detailed balance condition with an anti-unitary time reversal θ commuting with ρ, namely for all x,y ∈ and t ≥ 0. Our results also show that it is possible to find a standard form for the operators in the Lindblad representation of the generators extending the standard form of generators of quantum Markov semigroups satisfying the usual...
Random evolutions processes induced by discrete time Markov chains.
Recollement de semi-groupes de Feller locaux
Des semi-groupes de Feller locaux, deux à deux compatibles et définis sur des ouverts recouvrant un espace compact , se recollent en un semi-groupe de Feller local unique défini sur . Le principe du maximum joue un rôle essentiel dans la démonstration de ce résultat. Un théorème de recollement des générateurs infinitésimaux s’en déduit.
Reduction of a mean ergodic Markov semigroup on C(X) into its irreducible components.
Représentation d’un semigroupe d’opérateurs sur un espace par des noyaux. Remarques sur deux articles de S.E. Kuznetsov
Représentations de semigroupes par des opérateurs linéaires positifs sur C(X).
Reversibility for diffusions via quasi-invarience
Semi-group methods in stochastic control