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arXiv · 2010.09595

A Geometrical Model for the Evolution of Spherical Planetary Nebulae Based on Thin-Shell Formalism

S. Danial Forghani·Ibrahim Gullu·S. Habib Mazharimousavi
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Abstract

A spherical planetary nebula is described as a geometric model. The nebula itself is considered as a thin-shell which visualized as a boundary of two spacetimes. The inner and outer curvature tensors of the thin-shell are found in order to get an expression of the energy-momentum tensor on the thin-shell. The energy density and pressure expressions are derived using the energy-momentum tensor. The time evolution of the radius of the thin-shell is obtained in terms of the energy density. The model is tested by using a simple power function for decreasing energy density and the evolution pattern of the planetary nebula is attained.

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S. Danial Forghani, Ibrahim Gullu, S. Habib Mazharimousavi. 2020-10-19. A Geometrical Model for the Evolution of Spherical Planetary Nebulae Based on Thin-Shell Formalism. https://arxiv.org/abs/2010.09595

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