International Astronomy and Astrophysics Research Journal

On the Existence of a Hollow Neutron Star

Ramen Kumar Parui *

ARC, Room No-F101, Block-F, Mall Enclave, 13, K. B. Sarani, Kolkata-700080, India.

*Author to whom correspondence should be addressed.

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Abstract

Based on the Ni’s solution of Einstein Field Equations (EFE) we discuss the possibility of formation of a new type Neutron Star in which case the maximum density appears at a distance far from its center ( not at the center for normal neutron star case). As the inner core of such Neutron Star is a hollow sphere consideration of vacuum energy at the core offers the possibility of two types neutron star models — one with no exotic phase at the core and another one with a significant portion of it in the new phase. Ni’s solutions of EFE provide a new type neutron star model with hollow sphere in the inner core without violating the general relativity conditions. Based on the properties (i.e., findings of Ni’s solutions): a) void inside the center of the neutron star emerges naturally, and b) the solution leads to a mechanism for neutron stars to avoid collapse into black holes but remain regular, this author suggests the existence of a hollow neutron star is possible. If such type neutron stars really exist then it is also proposed that this new type Neutron Star can be detected through observation of electromagnetic counterpart by LIGO and VIRGO. Some problems related to this hollow neutron star are discussed.

Keywords: Field equations, exact solutions, relativistic stars, neutron star core, asymmetric matter

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