Finite Theories Before and After the Discovery of a Higgs Boson at the LHC

TL;DR

Finite Unified Theories, based on supersymmetry and reduction of couplings, can predict a Higgs mass consistent with LHC findings and suggest a heavy supersymmetric spectrum, aligning with experimental constraints.

Contribution

This paper demonstrates that finite supersymmetric GUTs can accurately predict the Higgs mass and supersymmetric particle spectrum in agreement with recent LHC results.

Findings

Predicted Higgs mass range of 121-126 GeV matches LHC discovery.

Favored models predict heavy supersymmetric particles above 1.5 TeV.

Constrained parameter space yields specific Higgs and superpartner spectra.

Abstract

Finite Unified Theories (FUTs) are N = 1 supersymmetric Grand Unified Theories (GUTs) which can be made finite to all-loop orders, based on the principle of reduction of couplings, and therefore are provided with a large predictive power. Confronting the predictions of SU(5) FUTs with the top and bottom quark masses and other low-energy experimental constraints a light Higgs-boson mass in the range M_h \sim 121-126 GeV was predicted, in striking agreement with the recent discovery of a Higgs-like state around \sim 125.5 GeV at ATLAS and CMS. Furthermore the favoured model, a finiteness constrained version of the MSSM, naturally predicts a relatively heavy spectrum with coloured supersymmetric particles above \sim 1.5 TeV, consistent with the non-observation of those particles at the LHC. Restricting further the best FUT's parameter space according to the discovery of a Higgs-like state and B-physics observables we find predictions for the rest of the Higgs masses and the supersymmetric particle spectrum.