15-20 June 2014
Laurentian University / Université Laurentienne
America/Toronto timezone
Welcome to the 2014 CAP Congress! / Bienvenue au congrès de l'ACP 2014!

Cosmological Perturbations in Antigravity

17 Jun 2014, 16:45
C-309 (Laurentian University / Université Laurentienne)


Laurentian University / Université Laurentienne

Sudbury, Ontario
Oral (Student, In Competition) / Orale (Étudiant(e), inscrit à la compétition) Theoretical Physics / Physique théorique (DTP-DPT) (T3-7) Cosmology - DTP / Cosmologie - DPT


Mr Marius Oltean (McGill University)


We compute the evolution of cosmological perturbations in a recently proposed Weyl-symmetric theory of two scalar fields with oppositely-signed kinetic terms and conformal couplings (in lieu of minimal coupling) to Einstein gravity. At the background level, the theory admits novel geodesically-complete cyclic cosmological solutions characterized by a brief period of repulsive gravity, or “antigravity,” during each successive transition from a Big Crunch to a Big Bang. We show that despite the wrong-signed kinetic term in the full action, these solutions are well-behaved (i.e. ghost-free) at the perturbative level.

Primary author

Mr Marius Oltean (McGill University)


Prof. Robert Brandenberger (McGill University)

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