A paper by PhD student David Benisty (pictured above) and Prof. Eduardo Guendelman (pictured below), both from the Department of Physics, has been awarded 2nd prize in an international competition organized by the Gravity Research Foundation.
The main purpose of the Foundation is to encourage scientific research and to arrive at a more complete understanding of the phenomenon of gravitation. The Foundation encourages such research through its annual awards for essays on gravitation with the expectation that beneficial uses will ensue.
The subject of the paper, entitled "Lorentzian Quintessential Inflation" is the construction of a model of the universe from its very early state to its present state. It is known that the universe has been expanding for a long time. The accelerated expansion of the late universe is explained by a very small "vacuum energy". However, in order to explain the homogeneity of the radiation from the big bang (the Cosmic Microwave Background radiation), researchers believe that the universe expands from very large vacuum energy briefly before the big bang. This theory called "the cosmic inflation" was invented originally by Prof. Eduardo Guendelman's supervisor – Prof. Alan Guth, when Guendelman was a Ph.D. student at MIT. It seems that both vacuum energies have some similar features, but with huge different rates.
The paper contributes to formulating a simple model of the whole story of the universe as the evolution of a single field - interpolating regions of high vacuum energy in the early universe and lower vacuum energy in the late universe. The big discrepancy between the early vacuum energy and the late one appears naturally in the model.