Dear all,
This Wed Nov 23 I will introduce the very important notion of density matrix. This is a central notion in quantum information and will occupy us till the end of the semester.
The density matrix generalizes the notion of state vector to statistical mixtures, and also to systems in contact with an environment. This will then allow to introduce the von Neumann entropy (the analog of Shannon's entropy) which is used to measure the "quantity of entanglement" and is also a basic "information measure".
best
Nicolas Macris
