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arXiv · 2311.18650

Perturbative Construction of Coherent States

Lasha Berezhiani·Giordano Cintia·Michael Zantedeschi
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Abstract

The perturbative consistency of coherent states within interacting quantum field theory requires them to be altered beyond the simple non-squeezed form. Building on this point, we perform explicit construction of consistent squeezed coherent states, required by the finiteness of physical quantities at the one-loop order. Extending this analysis to two-loops, we demonstrate that a non-Gaussian alteration of squeezed coherent states is necessary. The modifications of the coherent state we propose are perturbative in $\hbar$ and may be an indication that coherence must be viewed through a nonlinearly redefined, background-dependent, degree of freedom.

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Lasha Berezhiani, Giordano Cintia, Michael Zantedeschi. 2023-11-30. Perturbative Construction of Coherent States. https://arxiv.org/abs/2311.18650

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