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arXiv · astro-ph/9803013

Towards the Final State of Spherical Gravitational Collapse and Likely Source of Gamma Ray Bursts

Abstract

We invoke the global properties of the actual GTR field equations for spherical collapse to directly show that the condition for formation of trapped surfaces, 2GM/R >1 is not allowed by GTR. And therefore all singularity theorems based on the assumption of formation of trapped surfaces are invalidated! Our conclusion is in perfect agreement with Einstein's intuitive idea that a Sch. like surface can not occur in reality. Further as singularity is approached R ->0, in order that 2GM/R <= 1, we must have M ->0! Harrison, et al. had also pointed out that collapse should come to a decisive end with M=0. This is possible in GTR if the fluid radiates its entire original mass-energy during the relentless graviatational contraction process, Q->M c^2! Since the actual efficiency for gamma ray production by the relevant blast wave may hardly exceed 10-20% and there could be a stronger (undetected) nu-anti-nu burst precding GRBs, the actual energy released for GRB 990123, even accounting for probable weak beaming, or for GRB 971214 (unbeamed) could be ~10^{54-55} erg. And such energy release may not be properly accountable without realizing that trapped surfaces are indeed not formed. All authors concerned with this subject, and particularly those, who would like to differ with our derivation are requested to send their criticism either directly or express the same openly for a healthy scientific discussion.

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BibTeXRIS

Abhas Mitra. 1999-09-23. Towards the Final State of Spherical Gravitational Collapse and Likely Source of Gamma Ray Bursts. https://arxiv.org/abs/astro-ph/9803013

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