Speaker
Description
In this paper, we analyze the causal aspects of evolving marginally trapped surfaces in a D dimensional
spherically symmetric spacetime, sourced by perfect fluid with a cosmological constant. The norm of the
normal to the marginally trapped tube is shown to be the product of lie derivatives of the expansion
parameter of future outgoing null rays along the incoming and outgoing null directions. We obtain a closed
form expression for this norm in terms of principal density, pressure, areal radius and cosmological
constant. For the case of a homogeneous fluid distribution, we obtain a simple formula for determining the
causal nature of the evolving horizons. We obtain the causal phase portraits and highlight the critical radius.
We identify many solutions where the causal signature of the marginally trapped tube or marginally antitrapped tube is always null despite having an evolving area. These solutions do not comply with the
standard inner and outer horizon classification for degenerate horizons. We propose an alternate
prescription for this classification of these degenerate horizons
| sashideep@hyderabad.bits-pilani.ac.in | |
| Affiliation | BITS PILANI HYDERABAD CAMPUS |
