quinta-feira, agosto 21, 2014

Agravity

(Submitted on 17 Mar 2014 (v1), last revised 4 Jun 2014 (this version, v2))

We explore the possibility that the fundamental theory of nature does not contain any scale. This implies a renormalizable quantum gravity theory where the graviton kinetic term has 4 derivatives, and can be reinterpreted as gravity minus an anti-graviton. We compute the super-Planckian RGE of adimensional gravity coupled to a generic matter sector. The Planck scale and a flat space can arise dynamically at quantum level provided that a quartic scalar coupling and its β function vanish at the Planck scale. This is how the Higgs boson behaves for Mh≈125 GeV at Mt≈171 GeV. Within agravity, inflation is a generic phenomenon: the slow-roll parameters are given by the β-functions of the theory, and are small if couplings are perturbative. The predictions ns≈0.967 and r≈0.13 arise if the inflaton is identified with the Higgs of gravity. Furthermore, quadratically divergent corrections to the Higgs mass vanish: a small weak scale is natural and can be generated by agravity quantum corrections.

Comments:	24 pages. References added, final version to appear on JHEP
Subjects:	High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
Report number:	FTUAM-14-9, IFT-UAM/CSIC-14-021
Cite as:	arXiv:1403.4226 [hep-ph]
	(or arXiv:1403.4226v2 [hep-ph] for this version)