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arXiv · 1508.04277

Quantum renormalization group

S. Nagy·J. Polonyi·I. Steib
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Abstract

The observed IR and the spectator UV particles of a regulated, cutoff quantum field theory are entangled by their interactions; hence, the IR sector can be described by the help of the density matrix only. The tree-level renormalized trajectory is obtained for a self-interacting scalar field theory, containing the mixed state contributions. One needs a sharp cutoff in the momentum space as regulator to realize the true loss of information, caused by massive particles.

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S. Nagy, J. Polonyi, I. Steib. 2016-01-09. Quantum renormalization group. https://doi.org/10.1103/physrevd.93.025008

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