## Abstract

The cosmological constant problem and the absence of new natural physics at the electroweak scale, if confirmed by the LHC, may either indicate that the nature is fine-tuned or that a refined notion of naturalness is required. We construct a family of toy UV complete quantum theories providing a proof of concept for the second possibility. Low energy physics is described by a tuned effective field theory, which exhibits relevant interactions not protected by any symmetries and separated by an arbitrary large mass gap from the new "gravitational" physics, represented by a set of irrelevant operators. Nevertheless, the only available language to describe dynamics at all energy scales does not require any fine-tuning. The interesting novel feature of this construction is that UV physics is not described by a fixed point, but rather exhibits asymptotic fragility. Observation of additional unprotected scalars at the LHC would be a smoking gun for this scenario. Natural tuning also favors TeV scale unification.

Original language | English (US) |
---|---|

Article number | 45 |

Journal | Journal of High Energy Physics |

Volume | 2013 |

Issue number | 9 |

DOIs | |

State | Published - 2013 |

## Keywords

- Exact S-Matrix
- Models of Quantum Gravity
- Standard Model

## ASJC Scopus subject areas

- Nuclear and High Energy Physics