**Workshops and Seminars, Year 2009**

**16 - 12 - 2009 **ore 16:00 - Aula seminari III piano

Ricardo Castro Santis (Centro de Análisis Estocástico, Pontificia Universidad Católica de Chile): *Quantum Stochastic Calculus and Continual Measurement with Unbounded Coefficients*

**09 - 12 - 2009 **ore 14:30 - Aula seminari III piano

Alessandro Toigo (Politecnico di Milano): *Covariant positive operator valued measures and instruments: an overview.*

Covariance with respect to some symmetry group representation is a natural strong request imposed upon the whole set of measurements that can be performed on a quantum system, and, as such, it greatly simplifies their mathematical description. In this seminar, we present some general structure theorems for covariant positive operator valued measures and instruments, and apply them to two classes of measurements arising in quantum physics: the position and momentum measurements for a quantum particle, and the phase observables for the photon.

**11 - 11 - 2009 **ore 14:30 - Aula Seminari - III piano

Bassano Vacchini (Università degli Studi di Milano, Dipartimento di Fisica, Sezione Teorica): *Non-Markovian quantum evolutions*

We consider recent results on the description of non-Markovian dynamics for open quantum systems. In particular we discuss quantum semi-Markov processes. Semi-Markov processes represent a well known and widely used class of random processes in classical probability theory. Here, we develop an extension of this type of non-Markovian dynamics to the quantum regime. This extension is demonstrated to yield quantum master equations with memory kernels which allow the formulation of explicit conditions for the complete positivity of the corresponding quantum dynamical maps, thus leading to important insights into the structural characterization of the non-Markovian quantum dynamics of open systems.

**08 - 06 - 2009 **ore 11:00 - Aula Seminari III piano

Roberto Quezada (UAM - Mexico City): *Invariant states for the asymmetric exclusion quantum Markov semigroup*

We describe the structure of invariant states and projections of the asymmetric exclusion quantum Markov semigroup. (Joint work with J.C. Garcia and L.P. Martinez)