A meshless discrete Galerkin method for solving the universe evolution differential equations based on the moving least squares approximation

Authors

1 Department of Mathematics, Faculty of Sciences, Bu-Ali Sina University, Hamedan 65178, Iran

2 Department of Physic, Faculty of Sciences, Bu-Ali Sina University, Hamedan 65178, Iran

Abstract

In terms of observational data, there are some problems in the standard Big Bang cosmological model. Inflation era, early accelerated phase of the evolution of the universe, can successfully solve these problems. The inflation epoch can be explained by scalar inflaton field. The evolution of this field is presented by a non-linear differential equation. This equation is considered in FLRW model. In FLRW model, we consider the universe as the warped product of real line with a three dimensional homogeneous and isotropic manifold _ which could have positive, negative or zero curvature. The main aim of this paper is the numerical solution of the inflation evolution differential equations using of a meshless discrete Galerkin method. The method reduces the solution of these types of differential equations to the solution of Volterra integral equations of the second kind. Therefore, we solve these integral equations using moving least squares method. Finally, a numerical example is included to show the validity and efficiency of the new technique.

Keywords

References

 
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Iranian Journal of Astronomy and Astrophysics
Volume 4, Issue 2
ویژه نامه فارسی
October 2017
Pages 97-111

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