Non-Gaussianity in multiple three-form field inflation

• Autor(a) principal: Kumar, K. Sravan
• Data de Publicação: 2016
• Outros Autores: Mulryne, David J., Nunes, Nelson J., Marto, João, Moniz, Paulo
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.6/4615
• topic: Inflation; Primordial non-Gaussianity; δN formalism; Multiple three-forms

In this work, we present a method for implementing the δN formalism to study the primordial non-Gaussianity produced in multiple three-form field inflation. Using a dual description relating three-form fields to noncanonical scalar fields, and employing existing results, we produce expressions for the bispectrum of the curvature perturbation in terms of three-form quantities. We study the bispectrum generated in a two three-form field inflationary scenario for a particular potential that for suitable values of the parameters was found in earlier work to give values of the spectral index and ratio of tensor to scalar perturbations compatible with current bounds. We calculate the reduced bispectrum for this model, finding an amplitude in equilateral and orthogonal configurations of δ(1) and in the squeezed limit of δ(10-3). We confirm, therefore, that this three-form inflationary scenario is compatible with present observational constraints.