Cosmological α′-corrections from the functional renormalization group

Journal of High Energy Physics

Alessia Platania¹  Ivano Basile² 

[1] Perimeter Institute for Theoretical Physics, 31 Caroline St. N, N2L 2Y5, Waterloo, ON, Canada;Service de Physique de l’Univers, Champs et Gravitation, Université de Mons, Place du Parc 20, 7000, Mons, Belgium;

关键词: Cosmology of Theories beyond the SM;    String Duality;    Nonperturbative Effects;    Renormalization Group;   

DOI  :  10.1007/JHEP06(2021)045

来源: Springer

【 摘 要 】

We employ the techniques of the Functional Renormalization Group in string theory, in order to derive an effective mini-superspace action for cosmological backgrounds to all orders in the string scale α′. To this end, T-duality plays a crucial role, classifying all perturbative curvature corrections in terms of a single function of the Hubble parameter. The resulting renormalization group equations admit an exact, albeit non-analytic, solution in any spacetime dimension D, which is however incompatible with Einstein gravity at low energies. Within an E-expansion about D = 2, we also find an analytic solution which exhibits a non-Gaussian ultraviolet fixed point with positive Newton coupling, as well as an acceptable low-energy limit. Yet, within polynomial truncations of the full theory space, we find no evidence for an analog of this solution in D = 4. Finally, we comment on potential cosmological implications of our findings.

【 授权许可】

CC BY