Dynamical reconstruction of the $\Lambda$CDM model in scalar-tensor $f(R,T)$ gravity

Abstract

In this work, we use the dynamical system approach to explore the cosmological background evolution of the scalar-tensor representation of $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the stress-energy tensor. The motivation for this work resides in finding dynamical cosmological behaviors comparable with the $\Lambda$CDM model without the necessity of recurring to a dark energy component. We introduce a set of dynamical variables that allow for a direct comparison with the cosmological standard model and the current experimental measurements, and develop a dynamical system framework to analyze the cosmological evolution of Friedmann-Lemaître-Robertson-Walker (FLRW) universes within this theory. In this framework, we obtain the critical points in the cosmological phase space and perform fully numerical integrations of the dynamical system to extract the cosmological behavior, subjected to initial conditions compatible with the measurements by the Planck satellite. The phase space of the theory is proven to feature fixed points associated with cosmological behaviors analogous to those of GR, whereas variations in the scalar field associated to the dependency in $T$ affect the phase space structure only quantitatively. Our results indicate that cosmological solutions featuring a radiation dominated epoch, followed by a transition into a matter dominated epoch, and finally a transition into an exponentially accelerated epoch, are allowed by the theory, while maintaining a present state compatible with the current measurements from the Planck satellite and solar system dynamics, and preserving the regularity of the scalar fields and their interaction potential.

18 pages, 8 figures, 6 tables. Substantial changes made to first version

References in corpus (55)

• Dynamics of dark energy
• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• f(R,T) gravity
• Extra force in $f(R)$ modified theories of gravity
• f(R,L_m) gravity
• Nonminimal coupling of perfect fluids to curvature
• Generalized curvature-matter couplings in modified gravity
• Thermodynamic interpretation of the generalized gravity models with geometry - matter coupling
• Modelling wormholes in $f(R,T)$ gravity
• Inflation and late-time cosmic acceleration in non-minimal Maxwell-$F(R)$ gravity and the generation of large-scale magnetic fields
• Static Spherically Symmetric Wormholes in $f(R,T)$ Gravity
• Generalized energy conditions in Extended Theories of Gravity
• Compact stars in $f(R,T)$ gravity
• Dark Matter From f(R,T) Gravity
• Inflationary cosmology and the late-time accelerated expansion of the universe in non-minimal Yang-Mills-$F(R)$ gravity and non-minimal vector-$F(R)$ gravity
• Cosmological solutions from Induced Matter Model applied to 5D f(R,T) gravity and the shrinking of the extra coordinate
• Autonomous Dynamical System Approach for $f(R)$ Gravity
• Extended $f(R,L_m)$ gravity with generalized scalar field and kinetic term dependences
• Anisotropic cosmological models in $f(R,T)$ gravity with variable deceleration parameter
• Cosmological dynamics of Scalar--Tensor Gravity
• Some remarks on the dynamical systems approach to fourth order gravity
• Geodesic deviation, Raychaudhuri equation, and tidal forces in modified gravity with an arbitrary curvature-matter coupling
• Junction conditions and thin-shells in perfect-fluid $f\left(R,T\right)$ gravity
• Non-exotic traversable wormhole solutions in linear $f\left(R,T\right)$ gravity
• On dynamical systems approaches and methods in $f(R)$ cosmology
• Unveiling the Dynamics of the Universe
• Generalized dark gravity
• Cosmology in scalar-tensor $f(R,T)$ gravity
• Charged quark stars in $f(R,T)$ gravity
• Moment of inertia of slowly rotating anisotropic neutron stars in $f(R,T)$ gravity
• Dynamics of a parametrized dark energy model in $f(R,T)$ gravity
• Gravitationally induced particle production in scalar-tensor $f(R,T)$ gravity
• Cosmographic analysis of a closed bouncing universe with the varying cosmological constant in $f(R,T)$ gravity
• Gravitationally Induced Particle Production through a Nonminimal Torsion-Matter Coupling
• Slow-roll inflation in $f(R,T)$ gravity with a $RT$ mixing term
• Rapidly rotating neutron stars in $f(R,T)$ gravity
• Gravitational wave echoes from compact stars in $f(\mathcal{R},T)$ gravity
• Impact of compactlike and asymmetric configurations of thick branes on the scalar-tensor representation of $f\left(R,T\right)$ gravity
• Swampland dS conjecture in Mimetic $f(R,T)$ gravity
• Isotropic Buchdahl's relativistic fluid sphere within $f(R,T)$ gravity
• Inflationary Cosmology in the Modified $f(R,T)$ Gravity
• Dynamical system analysis of cosmological evolution in the Aether scalar tensor theory
• Lagrangian description of cosmic fluids: mapping dark energy into unified dark energy
• Curvature-matter couplings in modified gravity: from linear models to conformally invariant theories
• Junction conditions of Palatini $f\left(\mathcal{R},T\right)$ gravity
• On-shell Lagrangian of an ideal gas
• Reheating and particle creation in unimodular f(R, T) gravity
• Warm Inflation in $f(R,T)$ gravity
• The galaxy rotation curves in the $f(R,T)$ modified gravity formalism
• Dark Energy Nature in Logarithmic $f(R,T)$ Cosmology
• Beyond Einstein's General Relativity
• Inflationary Cosmology in a non-minimal $f(R,T)$ gravity theory using a $RT$ mixing term
• Wormhole generating function in $f(R,T)$ gravity
• Anisotropic Tolman V Solutions by Decoupling Approach in $f(R,T^2)$ Gravity
• Multi-kink braneworld configurations in the scalar-tensor representation of $f(R,T)$ gravity

Cited by in corpus (9)

• Dynamical systems of modified Gauss-Bonnet gravity: cosmological implications
• Dynamical reconstruction of the $\Lambda$CDM model in the scalar-tensor representation of $f\left(Q,T\right)$ gravity
• Dynamical reconstruction of the $\Lambda$CDM model in hybrid metric-Palatini gravity
• Constructing Viable Interacting Dark Matter and Dark Energy Models: A Dynamical Systems Approach
• Growth of cosmic perturbations in the modified $f(R,T)$ gravity
• Modified $f(R,T)$ theory in light of gravitational wave standard sirens
• Thermodynamics of a Non-canonical $f(\bar{R},\bar{T})$ gravity
• $\Lambda$CDM-like evolution in Einstein-scalar-Gauss-Bonnet gravity
• Lagrangian Identity and Mass Evolution of Particle-like Objects in Nonminimally Coupled Gravity