Double Shadow Of A Regular Phantom Black Hole As Photons Couple To Weyl Tensor

It is well known from general relativity that the deflection of light will be occurred in the gravitational field of compacted object.The direction of the light rays aimed originally at observer will be changed as they pass close to a black hole so that these light rays can not be detected by observer,and then a darker region appears in the observer's sky,which is so-called the shadow of the black hole.A lot of investigation indicate that the shadow carries some characteristic information about the black hole,which provides a new possible way to identify the black hole.In this thesis,we have studied the shadow of regular phantom black hole as photons couple to Weyl tensor,and obtain some interesting results.In the first chapter,we briefly introduced the basic theory of the shadow of the black hole illustrated by the cases of the static spherically symmetric black hole and Kerr black hole.Moreover,we also elaborated the model of dark energy,especially the phantom dark energy model.At last,we briefly presented the electromagnetic theory model with the coupling to Weyl tensor.In the second chapter,we studied the double shadow of a regular phantom black hole as photons couple to Weyl tensor.We find that the coupling yields that photons with different polarization directions propagate along different paths in the spacetime so that there exits double shadow for a single black hole,which is quite different from that in the non-coupling case where only a single shadow emerges.The umbra of black hole increases with the phantom charge and decreases with the coupling strength.The dependence of the penumbra on the phantom charge and the coupling strength is converse to that of the umbra.Combining with the supermassive central object in our Galaxy,we estimated the shadow of the black hole as the photons couple to Weyl tensor.Finally,we presented a summary and make some prospects of our study.