On the nature of the compact condensations at the centre of galaxies

Abhas Mitra

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On the nature of the compact condensations at the centre of galaxies

Abhas Mitra

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Abstract

There are many observational evidences for the existence of massive compact condensations in the range $10^6 -10^{10} M_\odot$ at the core of various galaxies. At present such condensations are commonly interpreted as Black Holes (BHs). However, we point out that while such Black Hole Candidates (BHCs) must be similar to BHs in many respects they, actually, can not be BHs because existence of Black Holes would violate the basic tenet of the General Theory of Relativity (GTR) that the worldline of a material particle must be timelike at any regular region of spacetime. On the other hand general relativistic collapse of very massive bodies should lead to Eternally Collapsing Configurations (ECOs) or Ultra Compact Objects (UCOs). While ECOs/UCOs may practically be as compact as corresponding BHs, they will have a physical surface. Also while BHs do not have any intrinsic magnetic field ECOs may have strong intrinsic magnetic field. We point out that despite many claims actually there is no real evidence for the ``Event Horizon'' (EH) of supposed BHs and on the other hand, there are tentative evidence for the existence of strong magnetic field in several BHCs (or ECOs). The presence of such intrinsic magnetic field may render the task of explaining high energy radiation phenomenon in many Active Galactic Nuclei easier.

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Abhas Mitra. 2002-05-16. On the nature of the compact condensations at the centre of galaxies. https://arxiv.org/abs/astro-ph/0205261

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