Nonlinear effects of gravity in cosmology

Modified gravity and cosmology

Lorentzian Gravity and Cosmology

If a material vacuum exists, with the properties of a superfluid through which already recognized material moves, then it is capable of acting as a universal reference frame and as an intermediary for the production of particle pairs throughout the universe, which as they cool and recombine, become the source of both high-and low-temperature cosmic background radiation, as observed. Moreover, i...

Nonlinear noise in cosmology.

This paper derives and analyzes exact, nonlocal Langevin equations appropriate in a cosmological setting to describe the interaction of some collective degree of freedom with a surrounding “environment.” Formally, these equations are much more general, involving as they do a more or less arbitrary “system,” characterized by some time-dependent potential, which is coupled via a nonlinear, time-d...

Cosmology of Nonlinear Oscillations

The nonlinear oscillations of a scalar field are shown to have cosmological equations of state with w = p/ρ ranging from −1 < w < 1. We investigate the possibility that the dark energy is due to such oscillations. ∗[email protected]

SHAPE OPTIMIZATION OF CONCRETE GRAVITY DAMS CONSIDERING DAM–WATER–FOUNDATION INTERACTION AND NONLINEAR EFFECTS

This study focuses on the shape optimization of concrete gravity dams considering dam–water–foundation interaction and nonlinear effects subject to earthquake. The concrete gravity dam is considered as a two–dimensional structure involving the geometry and material nonlinearity effects. For the description of the nonlinear behavior of concrete material under earthquake loads, the Drucker–Prager...