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arXiv · hep-th/9710241

Relative entropy in 2d Quantum Field Theory, finite-size corrections and irreversibility of the Renormalization Group

J. Gaite
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Abstract

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.

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J. Gaite. 1998-09-10. Relative entropy in 2d Quantum Field Theory, finite-size corrections and irreversibility of the Renormalization Group. https://doi.org/10.1103/physrevlett.81.3587

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