Global dynamics of the hyperbolic Chiral-Phantom model
Institute of Systems Science, Durban University of Technology, 4000, Durban, South Africa
2 Instituto de Ciencias Físicas y Matemáticas, Universidad Austral de Chile, Valdivia, Chile
3 Departamento de Matemáticas, Universidad Católica del Norte, Avda. Angamos 0610, Casilla, 1280, Antofagasta, Chile
Accepted: 12 January 2022
Published online: 24 January 2022
We perform a detailed analysis of the asymptotic behavior of a multi-field cosmological model with phantom terms. Specifically, we consider the Chiral-Phantom model consisting of two scalar fields with a mixed kinetic term, where one scalar field has negative kinetic energy, that is, it has phantom properties. We show that the Hubble function can change sign, and we study the global evolution of the field equations in the finite and infinity regions with the use of Poincaré variables. We find that in the Chiral-Phantom model the limit of the quintessence scalar field is recovered, while the cosmological evolution differs from the standard hyperbolic theory. Finally, the linear cosmological perturbations are studied.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022