Conveners
T4-4 General Relativity II (DTP) | Relativité générale II (DPT)
- Svetlana Barkanova (Acadia University)
Numerical studies of gravitational collapse to black holes used to predict gravitational waves make use of apparent horizons, which are intrinsically foliation-dependent. We discuss possible solutions to this problem using the Hawking-Hayward quasilocal mass. In spherical symmetry, a sensible approach consists of restricting to spherical spacetime slicings. Then the apparent horizons enjoy a...
The Tolman~VII solution for a static perfect fluid sphere
to the Einstein equations is reexamined, and a closed form
class of equations of state (EOSs) is deduced for the first time.
These EOSs allow further analysis to be carried out, leading to a
viable model for compact stars with arbitrary boundary mass density
to be obtained. Explicit application
of causality conditions...
In my talk I will discuss a recently discovered class of black holes which are the first such examples to exhibit a lambda-transition, that is a line of second order (continuous) phase transitions. The lambda-transition resembles those which occur in the context of condensed matter systems which, in the case of $^4$He marks the normal fluid/superfluid transition. The transition occurs within...
We construct several classes of exact wormhole solutions in 5-dimensional Einstein-Maxwell theory. We demonstrate that without requiring exotic matter, these spacetimes become singularity-free with an appropriate choice of parameters and maybe interpreted as models of charged or uncharged particles and particle-antiparticle pairs. We show that the electric field approaches Coulombic limit for...
Studies of massive rotating bodies in the context of General Relativity are mostly based, directly or indirectly, on the Kerr metric. The rotation is assumed from the start and investigators try to fit various parameters to mimic the observed phenomena. None of the current approaches starts from scratch and proposes a metric from which the rotation terms intrinsically emerge. Over the last CAP...
We study the possibility that a graviton in the presence of a black hole can be coherently amplified through stimulated emission. Because of the extremely weak coupling of gravitons to matter, the gain that can be obtained as the graviton passes through a lasing medium is untenably small, to achieve significant gains, with a typical absorption cross section, it will take a trajectory that is...
