6 research outputs found
Universal SSE algorithm for Heisenberg model and Bose Hubbard model with interaction
We propose universal SSE method for simulation of Heisenberg model with
arbitrary spin and Bose Hubbard model with interaction. We report on the first
calculations of soft-core bosons with interaction by the SSE method. Moreover
we develop a simple procedure for increase efficiency of the algorithm. From
calculation of integrated autocorrelation times we conclude that the method is
efficient for both models and essentially eliminates the critical slowing down
problem.Comment: 6 pages, 5 figure
Unified Model for Dark Energy
A new model for the universe filled with a generalized Chaplygin fluid is
considered which unitarily describes as a single vacuum entity both a
quintessence scalar field and a cosmological constant, so unifying the notion
of dark energy. While the evolution of the universe filled with such a fluid
does not obviously contradict the present cosmic acceleration, the introduced
single dark-energy component, for equations of state with characteristic
parameter , behaves like an usual quintessence fluid with
constant equation of state at early high densities, and like a pure
cosmological constant at late cosmological times.Comment: 5 pages, some misprints corrected, a comment on the initial equation
of state inserted, one reference adde