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Folding and Fundamental Groups of Flat Robertson-walker Space


Affiliations
1 Mathematics Department, Faculty of Science, Taibah University, Madinah, Saudi Arabia
 

This paper aims to give a combinatorial characterization and also construct representations of the fundamental groups of the submanifolds on flat Robertson-Walker space by using some geometrical transformations. The homotopy groups of the limit folding on flat Robertson-Walker space are presented. The homotopy groups of the retractions and deformation retract on flat Robertson-Walker space are obtained. The fundamental groups of some types of geodesics in the flat Robertson-Walker space are discussed. New types of homotopy maps are deduced. Theorems governing this connection are achieved.

Keywords

Flat Robertson-Walker Space W4, Homotopy Groups, Foldings, Retractions, Deformation Retracts
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  • Folding and Fundamental Groups of Flat Robertson-walker Space

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Authors

A. E. El-Ahmady
Mathematics Department, Faculty of Science, Taibah University, Madinah, Saudi Arabia

Abstract


This paper aims to give a combinatorial characterization and also construct representations of the fundamental groups of the submanifolds on flat Robertson-Walker space by using some geometrical transformations. The homotopy groups of the limit folding on flat Robertson-Walker space are presented. The homotopy groups of the retractions and deformation retract on flat Robertson-Walker space are obtained. The fundamental groups of some types of geodesics in the flat Robertson-Walker space are discussed. New types of homotopy maps are deduced. Theorems governing this connection are achieved.

Keywords


Flat Robertson-Walker Space W4, Homotopy Groups, Foldings, Retractions, Deformation Retracts

References





DOI: https://doi.org/10.17485/ijst%2F2013%2Fv6i4%2F31847