×

Mathematical model for Sagittarius \(\mathrm{A}^*\) and related Tolman-Oppenheimer-Volkoff equations. (English) Zbl 1538.83034

Summary: We analyze the model describing the interaction of relativistic gravitationally attracting diffusive fermionic particles evaporating at high energy motivated by the recent observations of star trajectories under the influence of the dark matter. We extend to the relativistic case the results for the Michie-King distribution obtained in our previous paper. We consider more general equation of state for the Tolman-Oppenheimer-Volkoff equation. By fixed point arguments, we prove the existence of solutions. Next, by pressure-density estimates, we show some restrictions on the data of the system. Finally, by numerical simulations, we depict the density profile governed by the specific equation of state adapted to the Sagittarius A* located in the centre of the Milky Way.
{© 2023 John Wiley & Sons, Ltd.}

MSC:

83C56 Dark matter and dark energy
85-10 Mathematical modeling or simulation for problems pertaining to astronomy and astrophysics
82B21 Continuum models (systems of particles, etc.) arising in equilibrium statistical mechanics
53Z05 Applications of differential geometry to physics
34B10 Nonlocal and multipoint boundary value problems for ordinary differential equations
Full Text: DOI

References:

[1] E. A.Becerra‐Vergara, C. R.Argüelles, A.Krut, J. A.Rueda, and R.Ruffini, Hinting a dark matter nature of Sgr A* via the S‐stars, Mon. Not. R. Astron Soc.505 (2021), 64-68.
[2] E.Giorgi, Stable black holes: in vacum and beyond, Bull. AMS60 (2023), 1-27. · Zbl 1513.83015
[3] D.Bors and R.Stańczy, Models of Michie‐King type, Commun. Math. Phys.382 (2021), 1243-1262. · Zbl 1467.82069
[4] J. R.Oppenheimer and G. M.Volkoff, On massive neutron cores, Phys. Rev.55 (1939), 374-381. · Zbl 0020.28501
[5] R. C.Tolman, Static solutions of Einstein’s field equations for spheres of fluid, Phys. Rev.55 (1939), 364-373. · JFM 65.1048.02
[6] C. R.Argüelles, A.Krut, J. A.Rueda, and R.Ruffini, Geodesic motion of S2 and G2 as a test of the fermionic dark matter nature of our Galactic core, Astron. Astrophys.641 (2020), A34.
[7] H. C.Ohanian and R.Ruffini, Gravitation and Spacetime, 2013. · Zbl 1264.53085
[8] H. A.Buchdahl, General relativistic fluid spheres, Phys. Rev.116 (1959), 1027-1034. · Zbl 0092.20802
[9] P. H.Chavanis, Gravitational instability of finite isothermal spheres in general relativity. Analogy with neutron stars, Astron. Astrophys.381 (2002), 709-730.
[10] P. H.Chavanis, Generalized thermodynamics and kinetic equations: Boltzmann, Landau, Kramers and Smoluchowski, Phys. A.332 (2004), 89-122.
[11] P. H.Chavanis, Relativistic stars with a linear equation of state: analogy with classical isothermal spheres and black holes, Astron. Astrophys.483 (2008), 673-698. · Zbl 1148.85303
[12] P.Biler and R.Stańczy, Parabolic‐elliptic systems with general density‐pressure relations, Variational Problems and Related Topics, M.Misawa (ed.) and T.Suzuki (ed.), (eds.), Vol. 1405, Sūrikaisekikenkyūsho Kōkyūroku, Kyoto, 2004, pp. 31-53.
[13] P.Biler and R.Stańczy, Nonlinear diffusion models for self‐gravitating particles, Free Boundary Problems Theory and Applications, J. F.Rodrigues (ed.) and L.Santos (ed.), (eds.), International Series of Numerical Mathematics, Vol. 154, Birkhäuser, Basel, 2006, pp. 107-116. · Zbl 1113.35328
[14] D.Bors and R.Stańczy, Dynamical system modeling fermionic limit, Discret. Contin. Dyn. Syst. B.23 (2018), 45-55. · Zbl 1374.35406
[15] P. H.Chavanis, Statistical mechanics and thermodynamic limit of self‐gravitating fermions in D dimensions, Phys. Rev. E.69 (2004), 066126.
[16] R.Stańczy, Steady states for a system describing self‐gravitating Fermi-Dirac particles, Differ. Integral Equ.18 (2005), 567-582. · Zbl 1212.35132
[17] R.Stańczy, Self‐attracting Fermi‐Dirac particles in canonical and microcanonical setting, Math. Methods Appl. Sci.28 (2005), 975-990. · Zbl 1068.35121
[18] H. J.deVega, P.Salucci, and N. G.Sanchez, Observational rotation curves and density profiles vs the Thomas-Fermi galaxy structure theory, Mon. Not. R Astron. Soc.442 (2014), 2717-2727.
[19] P. H.Chavanis and M.Lemou, Méhats F., Models of dark matter halos based on statistical mechanics: I. The classical King model, Phys. Rev.D.91 (2015), 63531.
[20] R. W.Michie, On the distribution of high energy stars in spherical stellar systems, Mon. Not. R Astron. Soc.125 (1962), 127-139.
[21] D.Bors and R.Stańczy, Existence and continuous dependence on parameters of radially symmetric solutions to astrophysical model of self-gravitating particles, Math. Meth. Appl. Sci.42 (2019), 7381-7394. · Zbl 1434.35242
[22] P. H.Chavanis, On the coarse‐grained evolution of collisionless stellar systems, Mon. Not. R Astron. Soc.300 (1998), 981-991.
[23] P. H.Chavanis, M.Lemou, and F.Méhats, Models of dark matter halos based on statistical mechanics: II. The fermionic King model, Phys. Rev. D.92 (2015), 123527.
[24] R.Ruffini and L.Stella, On semi‐degenerate equilibrium configurations of collisionless self‐gravitating Fermi gas, Astron. Astrophys.119 (1983), 35-41.
[25] G.Alberti and P. H.Chavanis, Caloric curves of self-gravitating fermions in general relativity, Eur. Phys. J.93 (2020), 208.
[26] N.Bilic, B. G.Tupper, and R. D.Viollier, Dark Matter in the Galaxy, Lect. Notes Phys.616 (2003), 24-38.
[27] R.Ruffini, C. R.Argüelles, and J. A.Rueda, On the core-halo distribution of dark-matter in galaxies, Mon. Not. R Astron. Soc.451 (2015), 622-628.
[28] P. H.Chavanis, Gravitational instability of polytropic spheres and generalized thermodynamics, Astron. Astrophys.386 (2002), 732-742.
[29] G.Alberti and P. H.Chavanis, Caloric curves of classical self-gravitating systems in general relativity, Phys. Rev. E101 (2020), no. 05, 2105.
[30] D.Bors and R.Stańczy, Dynamical system describing cloud of particles, J. Differ. Equ.342 (2023), 21-33. · Zbl 07615162
[31] P. H.Chavanis, Ph.Laurençot, and M.Lemou, Chapman‐Enskog derivation of the generalized Smoluchowski equation, Physica A.341 (2004), 145-164.
[32] J.Binney and S.Tremaine, Galactic dynamics, Princeton Series in Astrophysics, Princeton, 1987. · Zbl 1130.85301
[33] S.Chandrasekhar, The maximum mass of ideal white dwarf stars, Astrophys. J.74 (1931), 81-82. · Zbl 0002.23502
[34] S.Chandrasekhar, The highly collapsed configurations of a stellar mass, Mon. Not. R Astron. Soc.95 (1935), 207-225. · Zbl 0011.08503
[35] S.Chandrasekhar, An introduction to the study of stellar structure, 1958. Univ. Chicago Pub., reprinted by Dover Pub. · JFM 65.1543.02
[36] P. H.Chavanis, J.Sommeria, and R.Robert, Statistical mechanics of two‐dimensional vortices and collisionless stellar systems, Astrophys. J.471 (1996), 385-399.
[37] S.Chandrasekhar, A limiting case of relativistic equilibrium, General Relativity, papers in honour of J.L. Synge, L.O’Raifeartaigh (ed.), (ed.), Ofxord, 1972.
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.