How to predict a new physics scale and its uncertainty with the Inverse Amplitude Method

TL;DR

This paper discusses how to use the Inverse Amplitude Method to predict new physics scales and estimate uncertainties, extending the predictive power of effective field theories beyond their usual limits.

Contribution

It provides a practical guide on applying the Inverse Amplitude Method to identify resonances and quantify systematic uncertainties in Beyond the Standard Model physics searches.

Findings

Demonstrates how to predict a new physics resonance using the Inverse Amplitude Method.

Provides a systematic approach to estimate uncertainties in predictions.

Extends the applicability of effective field theories to higher energy scales.

Abstract

Effective Field Theories such as HEFT, organized as momentum expansions, are a controllable approximation to strong dynamics only near threshold, as they miss exact elastic unitarity, reducing their predictive power at a higher scale if small separations from the Standard Model are found at the LHC or elsewhere. Unitarized chiral perturbation theory extends their reach to the saturation of unitarity but, generally with unknown systematics. Here I present a brief "handbook" on how to put to use the Inverse Amplitude Method to predict a resonance (associated with a new physics scale in Beyond the Standard Model searches) and more especially on how to control its systematic uncertainties.