Departament d'Astronomia i Astrofísica
Universitat de València |

Interfaces in Numerical Relativistic Hydrodynamics

*Dr. Stephen Millmore*

*School of Mathematics, University of Southampton, England*

*Seminari del departament d'Astronomia i Astrofísica*

*Dijous 17 juny 2010*

*15:00*

**Resum**

*Current non-linear numerical simulations of neutron stars use single component models. However, evidence suggests that there are several different regions present within a neutron star. Qualitatively different behaviour is expected to occur within these regions and can be characterised by the equation of state. Problems arise when modelling a single component neutron star with a spatially varying equation of state, due to instabilities in the numerical methods. An alternative method of dealing with these regions is to use a multicomponent model. In such a case, level set methods can be used to track the interface between components. Boundary conditions must then be chosen and imposed at any interfaces to model the interaction between the ï¬‚uid components correctly. Such techniques have been used with success in Newtonian computational fluid dynamics. Here I shall present an extension of these techniques to relativistic situations, and construct a simple multicomponent star model in general relativity by applying this extension. I then will provide some insight into the extension of these techniques for multidimensional situations.*