Tensor networks-a new tool for old problems

A new renormalization group approach that maps lattice problems to tensor networks may hold the key to solving seemingly intractable models of strongly correlated systems in any dimension. A Physics Viewpoint on arXiv:0903.1069Comment: 5 pages, 2 figure

Quantum impurity in a magnetic environment

A unified perspective is given on a number of different problems involving the coupling of a localized quantum spin degree of freedom to the low energy excitations of an antiferromagnet, a spin glass, or a Kondo insulator. The problems are related to those in the class often referred to as "Bose Kondo".Comment: 10 pages, 2 figures, conference on Field Theory and Statistical Mechanics, Rome, June 2002 in honor of G. Jona-Lasini