TY - JOUR

T1 - Singularity avoidance in classical gravity from four-fermion interaction

AU - Bambi, Cosimo

AU - Malafarina, Daniele

AU - Marcianò, Antonino

AU - Modesto, Leonardo

N1 - Funding Information:
This work was supported by the NSFC grant No. 11305038 , the Shanghai Municipal Education Commission grant for Innovative Programs No. 14ZZ001 , the Thousand Young Talents Program , and Fudan University .

PY - 2014/6/27

Y1 - 2014/6/27

N2 - We derive the dynamics of the gravitational collapse of a homogeneous and spherically symmetric cloud in a classical set-up endowed with a topological sector of gravity and a non-minimal coupling to fermions. The effective theory consists of the Einstein-Hilbert action plus Dirac fermions interacting through a four-fermion vertex. At the classical level, we obtain the same picture that has been recently studied by some of us within a wide range of effective theories inspired by a super-renormalizable and asymptotically free theory of gravity. The classical singularity is replaced by a bounce, beyond which the cloud re-expands indefinitely. We thus show that, even at a classical level, if we allow for a non-minimal coupling of gravity to fermions, event horizons may never form for a suitable choice of some parameters of the theory.

AB - We derive the dynamics of the gravitational collapse of a homogeneous and spherically symmetric cloud in a classical set-up endowed with a topological sector of gravity and a non-minimal coupling to fermions. The effective theory consists of the Einstein-Hilbert action plus Dirac fermions interacting through a four-fermion vertex. At the classical level, we obtain the same picture that has been recently studied by some of us within a wide range of effective theories inspired by a super-renormalizable and asymptotically free theory of gravity. The classical singularity is replaced by a bounce, beyond which the cloud re-expands indefinitely. We thus show that, even at a classical level, if we allow for a non-minimal coupling of gravity to fermions, event horizons may never form for a suitable choice of some parameters of the theory.

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U2 - 10.1016/j.physletb.2014.05.013

DO - 10.1016/j.physletb.2014.05.013

M3 - Article

AN - SCOPUS:84901067386

VL - 734

SP - 27

EP - 30

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

ER -