Some models of relativistic radiating stars.

• Main Author: Mahlatji, Matsimele Ngwalodi .
• Other Authors: Govinder, Kesh S.
• Language: en_ZA
• Published: 2014
• Subjects: Stars.; Gravitational fields.; Einstein field equations.; Theses > Mathematics.
• Online Access: http://hdl.handle.net/10413/10616

In this dissertation we study radiating stars in strong gravitational elds. We generate new classes of exact solutions to the Einstein eld equations and the boundary condition applicable to radiating relativistic stars. The model of a radiating star in general relativity, matching to the Vaidya exterior spacetime, is reviewed. The boundary condition is converted to a Riccati equation and we consider both cases involving geodesic and non-geodesic particle trajectories. We present the metrics found previously. We rst solve the boundary condition for the geodesic case and nd the gravitational potentials which are expanding and shearing. This is a new result. Secondly the boundary condition is analysed for the non-geodesic case and we seek new gravitational potentials which are accelerating, expanding and shearing. We are able to identify only geodesic solutions for this second case; this appears to be a new class of models. The solutions found are presented in terms of elementary functions which are helpful in studying the physical properties. The new solutions found cannot be categorised in existing classes of known solutions; they are examples of a new generic class di erent from previous studies. The matter variables of the model are generated . === Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2012.