We study static solutions of the Tolman--Oppenheimer--Volkoff equations for spherically symmetric objects (stars) living in a space filled with the Chaplygin gas. Two cases are considered. In the normal case all solutions (excluding the de Sitter one) realize a three-dimensional spheroidal geometry because the radial coordinate achieves a maximal value (the "equator"). After crossing the equator, three scenarios are possible: a closed spheroid having a Schwarzschild-type singularity with infinite blue-shift at the "south pole", a regular spheroid, and a truncated spheroid having a scalar curvature singularity at a finite value of the radial coordinate. The second case arises when the modulus of the pressure exceeds the energy density (the phantom Chaplygin gas). There is no more equator and all solutions have the geometry of a truncated spheroid with the same type of singularity. We consider also static spherically symmetric configurations existing in a universe filled with the phantom Chaplygin gas only. In this case two classes of solutions exist: truncated spheroids and solutions of the wormhole type with a throat. However, the latter are not asymptotically flat and possess curvature singularities at finite values of the radial coordinate. Thus, they may not be used as models of observable compact astrophysical objects.

Tolman-Oppenheimer-Volkoff equations in presence of the Chaplygin gas: stars and wormhole-like solutions / V. Gorini; A.Yu. Kamenshchik; U. Moschella; V. Pasquier; A.A. Starobinsky. - In: PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY. - ISSN 1550-7998. - STAMPA. - 78:(2008), pp. 064064-064064. [10.1103/PhysRevD.78.064064]

Tolman-Oppenheimer-Volkoff equations in presence of the Chaplygin gas: stars and wormhole-like solutions

KAMENCHTCHIK, ALEXANDR;
2008

Abstract

We study static solutions of the Tolman--Oppenheimer--Volkoff equations for spherically symmetric objects (stars) living in a space filled with the Chaplygin gas. Two cases are considered. In the normal case all solutions (excluding the de Sitter one) realize a three-dimensional spheroidal geometry because the radial coordinate achieves a maximal value (the "equator"). After crossing the equator, three scenarios are possible: a closed spheroid having a Schwarzschild-type singularity with infinite blue-shift at the "south pole", a regular spheroid, and a truncated spheroid having a scalar curvature singularity at a finite value of the radial coordinate. The second case arises when the modulus of the pressure exceeds the energy density (the phantom Chaplygin gas). There is no more equator and all solutions have the geometry of a truncated spheroid with the same type of singularity. We consider also static spherically symmetric configurations existing in a universe filled with the phantom Chaplygin gas only. In this case two classes of solutions exist: truncated spheroids and solutions of the wormhole type with a throat. However, the latter are not asymptotically flat and possess curvature singularities at finite values of the radial coordinate. Thus, they may not be used as models of observable compact astrophysical objects.
2008
Tolman-Oppenheimer-Volkoff equations in presence of the Chaplygin gas: stars and wormhole-like solutions / V. Gorini; A.Yu. Kamenshchik; U. Moschella; V. Pasquier; A.A. Starobinsky. - In: PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY. - ISSN 1550-7998. - STAMPA. - 78:(2008), pp. 064064-064064. [10.1103/PhysRevD.78.064064]
V. Gorini; A.Yu. Kamenshchik; U. Moschella; V. Pasquier; A.A. Starobinsky
File in questo prodotto:
Eventuali allegati, non sono esposti

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/62111
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 61
  • ???jsp.display-item.citation.isi??? 56
social impact