Würzburg 2018 – scientific programme

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GR: Fachverband Gravitation und Relativitätstheorie

GR 11: Black Holes

GR 11.3: Talk

Thursday, March 22, 2018, 14:40–15:00, NW-Bau - HS3

The shadow of a collapsing dark star — Stefanie Schneider and •Volker Perlick — ZARM, U Bremen, 28359 Bremen

According to general relativity a black hole is seen as a black disc against a bright backdrop of light sources. This black disc is usually called the ``shadow'' of the black hole. A US-led coordinated project known as the Event Horizon Telescope, in partnership with a European project known as the BlackHoleCam, is under way to actually observe the shadow of the black hole candidates at the centre of our own galaxy and at the centre of M87. For theoretical considerations of the shadow, the black hole is usually considered as eternal, i.e., as existing in a time-independent state forever. Here we ask the question of how the shadow comes about in the course of time if a black hole is formed by gravitational collapse. We consider the simplest model of a gravitational collapse, assuming that the collapsing ``star'' is a dark ball of dust.