MG11 
Talk detail
 

 Participant 

Institution

Session

Talk

Abstract

Simulating a Phase Transition in FRW Cosmology by the Multi-Josephson-Junction Loop

There is a dramatic discrepancy between the predicted number of topological defects formed by the phase transitions in early Universe and the observational constraints on their concentration. To resolve this problem, a number of laboratory simulations of the strongly-nonequilibrium symmetry-breaking phase transitions was undertaken in the last decade in various systems, such as liquid crystals, superfluids, and superconductors. The present report discusses the cosmological consequences of the multi-Josephson-junction loop (MJJL) experiment, which represents a close analog of 1D FRW cosmological model. As is shown, the specific nonlocal thermal correlations between the phases of order parameter, revealed in MJJL, reduce substantially the resulting number of topological defects. Moreover, such suppression is expected to be even more efficient in 2D and 3D cases.

Testing the Dark-Energy-Dominated Cosmology by the Solar-System Experiments

The effect of dark energy is sought for at interplanetary scales by comparing the rates of secular increase in the lunar orbit obtained by two ways: (1) measured immediately by the laser ranging and (2) estimated independently from deceleration of the Earth's proper rotation. The first quantity involves both the well-known effect of geophysical tides and the Kottler's effect of Lambda-term, while the second one is associated only with tidal influence. The main problem of the analysis is poor knowledge of the second quantity. For example, if it is taken from astrometric observations of Earth's deceleration for the last 350 years, a reasonable agreement with intergalactic data can be achieved. On the other hand, if the altimetric data on tidal deformations are used, the effect of Lambda-term is substantially reduced but, nevertheless, remains significantly different from zero.