One-loop effective potential of N=1 supersymmetric theory and decoupling effects

TL;DR

This paper analyzes one-loop decoupling effects in N=1 supersymmetric theories, showing how heavy fields influence low-energy couplings and the potential impact on string theory vacua predictions.

Contribution

It provides explicit calculations of decoupling effects at one-loop in supersymmetric models, including non-minimal couplings and string-inspired scenarios.

Findings

Decoupling effects grow logarithmically with heavy mass M.

Quantum corrections can modify low-energy couplings significantly.

Decoupling influences vacuum stabilization and low-energy predictions.

Abstract

We study the decoupling effects in N=1 (global) supersymmetric theories with chiral superfields at the one-loop level. The examples of gauge neutral chiral superfields with the minimal (renormalizable) as well as non-minimal (non- renormalizable) couplings are considered, and decoupling in gauge theories with U(1) gauge superfields that couple to heavy chiral matter is studied. We calculate the one-loop corrected effective Lagrangians that involve light fields and heavy fields with mass of order M. The elimination of heavy fields by equations of motion leads to decoupling effects with terms that grow logarithmically with M. These corrections renormalize light fields and couplings in the theory (in accordance with the "decoupling theorem"). When the field theory is an effective theory of the underlying fundamental theory, like superstring theory, where the couplings are calculable, such decoupling effects modify the low-energy predictions for the effective couplings of light fields. In particular, for the class of string vacua with an "anomalous" U(1) the vacuum restabilization triggers the decoupling effects, which can significantly modify the low energy predictions for the couplings of the surviving light fields. We also demonstrate that quantum corrections to the chiral potential depending on massive background superfields and corresponding to supergraphs with internal massless lines and external massive lines can also arise at the two-loop level.