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Deep surveys indicate a bubbly structure on cosmological large scales which should be the result of evolution of primordial density perturbations. Several models have been proposed to explain the origin and dynamics of such features but, till now, no exhaustive and fully consistent theory has been found. We discuss a model where cosmological black holes, deriving from primordial perturbations, are the seeds for large-scale-structure voids. We give details of the dynamics and accretion of the system voids-cosmological black holes from the epoch $z\simeq10^{3}$till now, finding that a void of $40~h^{-1}$Mpc diameter and under-density of -0.9 fits the observations without conflicting with the homogeneity and isotropy of the cosmic microwave background radiation.

Abstract: The probability representation for quantum states of the universe in which the states are described by a fair probability distribution instead of wave function (or density matrix) is developed to consider cosmological dynamics. The evolution of the universe state is described by standard positive transition probability (tomographic transition probability) instead of the complex transition probability amplitude (Feynman path integral) of the standard approach. The latter one is expressed in terms of the tomographic transition probability. Examples of minisuperspaces in the framework of the suggested approach are presented. Possibility of observational applications of the universe tomographs are discussed.

Abstract: The notion of standard positive probability distribution function (tomogram) which describes the quantum state of the universe alternatively to the wave function or to the density matrix is introduced. Connection of the tomographic probability distribution with the Wigner function of the universe and with the star-product (deformation) quantization procedure is established.Using the Radon transform, the Wheeler-De Witt generic equation for the probability function is written in tomographic form. Some examples of the Wheeler-DeWitt equation in the minisuperspace are elaborated explicitly for homogeneous isotropic cosmological models. Some interpretational aspects of the probability description of the quantum state are discussed.

We derive the cavity optical axis length fluctuations induced by tilts of the cavity mirrors in presence of the gravitational field of the earth. By comparison with the typical tilt-induced noises we show that this potential source of noise is negligible for the first operation gravitational wave interferometers. The possibility of utilizing the effect to perform a measurement of the post-Newtonian prameter γin improved-operation interferometers is discussed.

The small algebra of loop functionals, defined by Rovelli and Smolin, on the Ashtekar phase space of general relativity is studied. Regarded as coordinates on the phase space, the loop functionals become degenerate at certain points. All the degenerate points are found and the corresponding degeneracy is discussed. The intersection of the set of degenerate points with the real slice of the constraint surface is shown to correspond precisely the Goldberg-Kerr solutions. The evolution of the holonomy group of Ashtekar's connection is examined, and the complexification of the holonomy group is shown to be preserved under it. Thus, an observable of the gravitational field is constructed.

Analyzing the Klein-Gordon equation in a homogeneous, Isotropic and spatially flat universe model, we find the conditions for the existence of a universe dominated by a scalar field in its early stages.