A Bayesian Model of Credence in Low Energy Supersymmetry

TL;DR

This paper uses Bayesian analysis to evaluate how empirical data, especially from the LHC, influences the scientific community's confidence in low energy supersymmetry, considering different optimism or pessimism attitudes.

Contribution

It introduces a Bayesian framework to quantify credences in low energy SUSY and assesses the impact of LHC data on these beliefs under various observer assumptions.

Findings

LHC data moderately decreases credence in low energy SUSY for optimistic observers.

Pessimistic observers maintain high credence despite LHC data.

Overall, credences remain substantial even after considering empirical constraints.

Abstract

We carry out a quantitative Bayesian analysis of the evolution of credences in low energy supersymmetry (SUSY) in light of the most relevant empirical data. The analysis is based on the assumption that observers apply principles of optimism or pessimism about theory building in a coherent way. On this basis, we provide a rough assessment of the current range of plausible credences in low energy SUSY and determine in which way LHC data changes those credences. For observers who had been optimistic about low energy SUSY before the LHC, the method reports that LHC data does lead to decreased credences in accordance with intuition. The decrease is moderate, however, and keeps posteriors at very substantial levels. The analysis further establishes that a very high but not yet indefensible degree of pessimism regarding the success chances of theory building still results in quite significant credences in GUT and low energy SUSY for the time right before the start of the LHC. The pessimist's credence in low energy SUSY remains nearly unchanged once LHC data is taken into account.