Abstract In this work, we use a combined approach of Hubble parameter data together with redshift-space-distortion ( f σ 8 ) data, which are used to reconstruct the teleparallel gravity (TG) Lagrangian via Gaussian processes (GP). The adopted mainly comes from cosmic chronometers, while for Type Ia supernovae latest jointly calibrated Pantheon compilation. Moreover, consider two main GP covaria...

In a recent work, it has been proposed that the cosmic passage to acceleration era is result of existence small anti-gravity sources in each galaxy and clusters galaxies. particular, swiss-cheese cosmology model which relativistically integrates contribution all these on galactic scale constructed assuming presence an infrared fixed point for dependent cosmological constant. The derived expansi...

wewanttofindthecosmologicalconstantinfluenceoncosmicmicrowavebackground(cmb)temperatureduetomovinglinearcosmicstrings.usingthespace-timemetricofalinearcosmicstringinanacceleratedexpandinguniverse,thegott-kaiser stebbins(gks)effect,asanimportantmechanisminproducingtemperaturediscontinuityinthe(cmb),isconsidered;then,itsmodificationduetotheeffectofthecosmologicalconstantiscalculated.theresultshowsthat...

In this paper the second Lyapunov method is used to study the stability of the de Sitter phase of cosmic expansion when the source of the gravitational field is a viscous fluid. Different inflationary scenarios related with reheating and decay of mini-blackholes into radiation are investigated using an effective fluid described by time–varying thermodynamical quantities.

We find the power-law solutions in (4+n)-dimensional cosmology with time-varying cosmological constant and study the phase of cosmic evolution. The model corresponds to the modification of the higher dimensional vacuum Kasner model. When a dimensionfull parameter in the model takes special value, it is shown that 4-dimensional universe is accelerated expansion. ∗[email protected]

Gravitational lenses, besides being interesting in their own right, have been demonstrated to be suitable as "gravitational standard rulers" for the measurement of the rate of expansion of the Universe (Ho), as well as to constrain the values of the cosmological parameters such as Omegao and Lambdao that control the evolution of the volume of the Universe with cosmic time.

Braneworld theory provides a natural setting to treat, at a classical level, the cosmological effects of vacuum energy. Non-static extra dimensions can generally lead to a variable vacuum energy, which in turn may explain the present accelerated cosmic expansion. We concentrate our attention in models where the vacuum energy decreases as an inverse power law of the scale factor. These models ag...