Regular Article - Theoretical Physics
Avoiding instabilities in antisymmetric tensor field driven inflation
Department of Physics, Indian Institute of Science Education and Research, Bhopal, 462066, India
* e-mail: firstname.lastname@example.org
Accepted: 14 September 2019
Published online: 23 September 2019
Models of inflation with antisymmetric tensor studied in the past are plagued with ghost instability even in an unperturbed FRW background. We show that it is possible to avoid ghosts in an unperturbed FRW background by considering the most general kinetic term for antisymmetric tensor field. The kinetic part acquires a new gauge symmetry violating term whose effect on perturbed modes is to prevent the appearance of nondynamical modes, and thus avoid ghosts. For completeness, we perform a check for gradient instability and derive the conditions for perturbations to be free of gradient instability.
© The Author(s), 2019