Relative entropy in 2d Quantum Field Theory, finite-size corrections and irreversibility of the Renormalization Group
Abstract
Description
The relative entropy in two-dimensional Field Theory is studied for its application as an irreversible quantity under the Renormalization Group, relying on a general monotonicity theorem for that quantity previously established. In the cylinder geometry, interpreted as finite-temperature field theory, one can define from the relative entropy a monotonic quantity similar to Zamolodchikov's c function. On the other hand, the one-dimensional quantum thermodynamic entropy also leads to a monotonic quantity, with different properties. The relation of thermodynamic quantities with the complex components of the stress tensor is also established and hence the entropic c theorems are proposed as analogues of Zamolodchikov's c theorem for the cylinder geometry.
5 pages, Latex file, revtex, reorganized to best show the generality of the results, version to appear in Phys. Rev. Lett
5 pages, Latex file, revtex, reorganized to best show the generality of the results, version to appear in Phys. Rev. Lett