Speaker
Dr
Plamen Fiziev
(Sofia University Foundation for Theoretical Physics and Astrophysics)
Description
The well-known serious difficulties in numerical investigation of realistic models of neutron stars (NS) in the modified theories of gravity [1] are surmounted on a general basis. Developing the recent results of the author [2-4] we present a realistic model of static spherically symmetric NS with AMP1 EOS using the correct boundary conditions at the center, at the edge, and at the cosmological horizon of the de Sitter like Universe with only one such star. The critical step is the introduction of new field variable for the scalar degree of freedom which we call “the dark scalar”. The maximal mass or the NS turns to be around 2.7 solar masses and depends on the mass of the dark scalar. We investigate for the first time this dependence, as well as the influence of the dark scalar on the gravitational field inside the NS and its exponentially decreasing dark halo outside the star. The dark halo may give some 15 % of the total mass of the NS. The behavior of the newly introduced pressure and mass density of the dark matter and dark energy are also studied and discussed.
References:
1. E. Berti et al, Testing General Relativity with Present and Future Astrophysical Observations, TOPICAL REVIEW, Class.Quant. Grav. (2015); arXiv:1501.07274.
2. P.P. Fiziev, PRD 87, 0044053 (2013); arXiv:1209.2695.
3. P.P. Fiziev, PoS (FFP14) 080 (1914); arXiv:1402.2813, arXiv:1411.0242.
4. P.P. Fiziev, K. Marinov, BAJ, 23, (2015); arXiv:1412.3015.
Primary author
Dr
Plamen Fiziev
(Sofia University Foundation for Theoretical Physics and Astrophysics)