Anomalies and renormalization of mixed states in quantum theories

  title={Anomalies and renormalization of mixed states in quantum theories},
  author={Kumar S. Gupta and Amilcar R. de Queiroz},
  journal={Modern Physics Letters A},
In a Hamiltonian approach to anomalies, parity and time-reversal symmetries can be restored by introducing suitable impure (or mixed) states. However, the expectation values of observables such as the Hamiltonian diverges in such impure states. Here, we show that such divergent expectation values can be treated within a renormalization group (RG) framework, leading to a set of β-functions in the moduli space of the operators representing the observables. This leads to well-defined expectation… 
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