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In this work a satisfactory, simple theoretical prediction of the data corresponding to observationally (by fine tuning condition) estimated value of the cosmological constant is given. It is supposed (in conceptually analogy with holographic principle) that cosmological constant, like classical surface tension coefficient by a liquid drop, does not correspond to a volume (bulk) vacuum mass (energy) density distribution but that it corresponds to a surface vacuum mass (energy) density distribution. Then form of given surface mass distribution and fine tuning condition imply observed growing (for $sim$ 61 magnitude order) of the scale factor (from initial, corresponding to Planck length, to recent, at the beginning of the cosmic acceleration, corresponding to 10 Glyr length).
We will look for an implementation of new symmetries in the space-time structure and their cosmological implications. This search will allow us to find a unified vision for electrodynamics and gravitation. We will attempt to develop a heuristic model
In this work we suggest (in a formal analogy with Linde chaotic inflation scenario) simple dynamical model of the dark energy or cosmological constant. Concretely, we suggest a Lagrangian dependent of Universe scale factor and scalar field (with cons
We derive a model of dark energy which evolves with time via the scale factor. The equation of state $omega=(1-2alpha)/(1+2alpha)$ is studied as a function of a parameter $alpha$ introduced in this model. In addition to the recent accelerated expansi
In an earlier paper, it is proposed that, due to resonance tunneling effect, tunneling from a large cosmological constant $Lambda$ site in the stringy comic landscape can be fast, while tunneling from a small $Lambda$ site may take exponentially long
We consider a model with two parallel (positive tension) 3-branes separated by a distance $L$ in 5-dimensional spacetime. If the interbrane space is anti-deSitter, or is not precisely anti-deSitter but contains no event horizons, the effective 4-dime