Upcoming seminars

Environment Induced Decoherence is a physical concept which provides a dynamical explanation to the disappearance of quantum phenomenon in the real world. Intuitively, it states that a quantum system is never per- fectly isolated, so that quantum correlations disappear due to the action of the environment on the system. Focusing on finite-dimensional quantum systems undergoing Markovian evolutions, we propose natural generaliza- tions of certain non-commutative functional inequalities that are adapted to the study of decoherence.

This talk will consist of two parts. In the first part, 
I will present the irreducible form of a Matrix Product States (MPS),
which is a generalization of the canonical form of an MPS in the 
sense that it is also defined for states with periodicity. I will 
then present a fundamental theorem for MPS in irreducible form, 
namely one that specifies how two tensors in irreducible form are 
related if they give rise to the same MPS. Finally, I will present
two applications of this result: an equivalence between the 

It is generally believed that quantum computers can perform certain tasks faster than their classical counterparts. Identifying the resource that potentially enables this speedup is of particular interest in quantum information science. In this talk, by using the well-developed theory of phase-space quasiprobability distributions, I present two sufficient conditions for efficient classical simulation of quantum-optics experiments. These conditions show that the negativity of the phase-space quasiprobability distributions is an essential resource for quantum speedup.

This thesis is concerned with a seemingly naive question: what happens when you separate two physical systems that were previously together? One of the greatest discovery of the last century is that systems that obey quantum mechanical instead of classical laws remain inextricably linked even after they are physically separated, a phenomenon known as entanglement. This leads immediately to another, deep question: is entanglement an exclusive feature of quantum systems, or is it common to all non-classical theories?