Spherical collapse and virialization in $f(T)$ gravities

Abstract

Using the classical top-hat profile, we study the non-linear growth of spherically symmetric density perturbation and structure formation in $f(T)$ gravities. In particular, three concrete models, which have been tested against the observation of large-scale evolution and linear perturbation of the universe in the cosmological scenario, are investigated in this framework, covering both minimal and nonminimal coupling cases of $f(T)$ gravities. Moreover, we consider the virialization of the overdense region in the models after they detach from the background expanding universe and turn around to collapse. We find that there are constraints in the magnitude and occurring epoch of the initial perturbation. The existence of these constraints indicates that a perturbation that is too weak or occurs too late will not be able to stop the expanding of the overdense region. The illustration of the evolution of the perturbation shows that in $f(T)$ gravities, the initial perturbation within the constraints can eventually lead to clustering and form structure. The evolution also shows that nonminimal coupling models collapse slower than the minimal coupling one.

19 pages,5 figures

References in corpus (16)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Dark torsion as the cosmic speed-up
• Einstein's Other Gravity and the Acceleration of the Universe
• Extra force in $f(R)$ modified theories of gravity
• The teleparallel equivalent of general relativity
• f(R,L_m) gravity
• Nonminimal coupling of perfect fluids to curvature
• Modified gravity with arbitrary coupling between matter and geometry
• $f(T,\mathcal{T})$ gravity and cosmology
• Generalizations of teleparallel gravity and local Lorentz symmetry
• Good and bad tetrads in f(T) gravity
• Nonminimal torsion-matter coupling extension of f(T) gravity
• Structure formation in the presence of dark energy perturbations
• Generalized virial theorem in f(R) gravity
• New derivation of the Lagrangian of a perfect fluid with a barotropic equation of state
• The spherical collapse model and cluster formation beyond the $\Lambda$ cosmology: Indications for a clustered dark energy?

Cited by in corpus (3)

• Spherically symmetric configuration in $f(Q)$ gravity
• New proper tetrad for teleparallel gravities in non-flat spacetime
• Action functional of the Cardassian universe