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arXiv · 1109.3821

On the viability of gravitational Bose-Einstein condensates as alternatives to supermassive black holes

Abstract

Black holes are inevitable mathematical outcome of spacetime-energy coupling in general relativity. Currently these objects are of vital importance for understanding numerous phenomena in astrophysics and cosmology. However, neither theory nor observations have been capable of unequivocally prove the existence of black holes or granting us an insight of what their internal structures could look like, therefore leaving researchers to speculate about their nature. In this paper the reliability of supermassive Bose-Einstein condensates (henceforth SMBECs) as alternative to supermassive black holes is examined. Such condensates are found to suffer of a causality problem that terminates their cosmological growth toward acquiring masses typical for quasars and triggers their self-collapse into supermassive black holes (SMBHs). It is argued that a SMBEC-core most likely would be subject to an extensive deceleration of its rotational frequency as well as to vortex-dissipation induced by the magnetic fields that thread the crust, hence diminishing the superfluidity of the core. Given that rotating superfluids between two concentric spheres have been verified to be dynamically unstable to non axi-symmetric perturbations, we conclude that the remnant energy stored in the core would be sufficiently large to turn the flow turbulent and dissipative and subsequently lead to core collapse bosonova. The feasibility of a conversion mechanism of normal matter into bosonic condensates under normal astrophysical conditions is discussed as well. We finally conclude that in lack of a profound theory for quantum gravity, BHs should continue to be the favorite proposal for BH candidates.

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BibTeXRIS

A. A. Hujeirat. 2011-09-20. On the viability of gravitational Bose-Einstein condensates as alternatives to supermassive black holes. https://doi.org/10.1111/j.1365-2966.2012.21102.x

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