Mass-radius relation of compact objects

Maximum mass-radius ratios for charged compact general relativistic objects

– Upper limits for the mass-radius ratio and total charge are derived for stable charged general relativistic matter distributions. For charged compact objects the mass-radius ratio exceeds the value 4/9 corresponding to neutral stars. General restrictions for the red shift and total energy (including the gravitational contribution) are also obtained. It is generally accepted today that black h...

Maximum Mass-Radius Ratio for Compact General Relativistic Objects in Schwarzschild- de Sitter Geometry

Upper limits for the mass-radius ratio are derived for arbitrary general relativistic matter distributions in the presence of a cosmological constant. General restrictions for the red shift and total energy (including the gravitational contribution) for compact objects in the Schwarzschild-de Sitter geometry are also obtained in terms of the cosmological constant and of the mean density of the ...

Mass-radius Relation for Magnetic White Dwarfs

Recently, several white dwarfs with very strong surface magnetic fields have been observed. In this paper we explore the possibility that such stars could have sufficiently strong internal fields to alter their structure. We obtain a revised white dwarf mass-radius relation in the presence of strong internal magnetic fields. We first derive the equation of state for a fully degenerate ideal ele...

Radius Mass Position of Radius

Direct Detection of Intermediate Mass Compact Objects via Submillilensing

A galaxy-sized halo may contain a large number of intermediate mass 10M⊙ compact objects (IMCOs), which can be intermediate mass black holes (IMBHs) or the CDM subhalos. We propose to directly detect the IMBHs by observing multiply imaged QSO-galaxy lens systems with a high angular resolution (∼ 0.03mas), which would be achieved by the next-VLBI space missions. The silhouette of the IMBHs would...