A pure geometric approach to stellar structure

• Authors: Mamdouh Wanas , Samah Ammar
• Languages of publication: EN

Abstracts

EN

The present work represents a step in dealing with stellar structure using a pure geometric approach. Geometric field theory is used to construct a model for a spherically symmetric configuration. In this case, two solutions have been obtained for the field equations. The first represents an interior solution which may be considered as a pure geometric one in the sense that the tensor describing the material distributions is not a phenomenological object, but a part of the geometric structure used. A general equation of state for a perfect fluid, is obtained from, and not imposed on, the model. The second solution gives rise to Schwarzschild exterior field in its isotropic form. The two solutions are matched, at a certain boundary, to evaluate the constants of integration. The interior solution obtained shows that there are different zones characterizing the configuration: a central radiation dominant zone, a probable convection zone as a physical interpretation of the singularity of the model, and a corona like zone. The model may represent a type of main sequence stars. The present work shows that Einstein’s geometerization scheme can be extended to gain more physical information within material distribution, with some advantages.

Keywords

EN

stellar structure; geometric field theories; main sequence stars; absolute parallelism geometry

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2013
• Volume: 11
• Issue: 7
• Pages: 936-948

Dates

published

1 - 7 - 2013

online

17 - 10 - 2013

Contributors

author

Mamdouh Wanas

author

Samah Ammar

• Mathematics Department, Faculty of Girls, Ain Shams University Heliopolis, Cairo, Egypt

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Identifiers

DOI

10.2478/s11534-013-0278-1