2020/11/30 by Manuel Gonzalez-Espinoza, Giovanni Otalora
Physics and Astronomy · #Advanced Differential Geometry Research #Attractor #Black Holes and Theoretical Physics #Cosmology #Cosmology and Gravitation Theories #Dark energy #Dark fluid #Dark matter #Lambda-CDM model #Scalar (mathematics) #Scaling #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1140/epjc/s10052-021-09270-x
Accepted version for publication in EPJC. 17 pages, 3 tables and 10 figures
openalex created_date 2020/11/23 · openalex publication_date 2021/05/01 · arxiv created 2021/05/23 · arxiv updated 2021/06/16 · openalex updated_date 2026/08/05
Abstract It is investigated the cosmological dynamics of scalar-torsion f(T,φ ) <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>f</mml:mi> <mml:mo>(</mml:mo> <mml:mi>T</mml:mi> <mml:mo>,</mml:mo> <mml:mi>ϕ</mml:mi> <mml:mo>)</mml:mo> </mml:mrow> </mml:math> gravity as a dark energy model, where T is the torsion scalar of teleparallel gravity and φ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ϕ</mml:mi> </mml:math> is a canonical scalar field. In this context, we are concerned with the phenomenology of the class of models with non-linear coupling to gravity and exponential potential. We obtain the critical points of the autonomous system, along with the stability conditions of each one of them and their cosmological properties. Particularly, we show the existence of new attractors with accelerated expansion, as well as, new scaling solutions in which the energy density of dark energy scales as the background fluid density, thus, defining the so-called scaling radiation and scaling matter epochs. The scaling solutions are saddle points, and therefore, the system exits these solutions to the current epoch of cosmic acceleration, towards an attractor point describing the dark energy-dominated era.