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arXiv · 2602.13431

Fixing EFT equations with a reservoir model

A. Besharat·L. Lehner·J. Radkovski
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Abstract

Effective Field Theories with higher derivatives often yield equations of motion which define ill-posed problems. We present a method for enhancing control on such theories by coupling them to a field living in one extra dimension. The resulting action principle helps to define a well-posed problem introducing a mechanism to control UV behavior. Physically this is achieved by dissipating the energy in the short-wavelength modes into the extra dimension. We examine the resulting dynamics and compare it to alternative proposals for studying such theories in the non-linear regime.

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A. Besharat, L. Lehner, J. Radkovski. 2026-02-13. Fixing EFT equations with a reservoir model. https://arxiv.org/abs/2602.13431

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