centra

<p>Abstract:</p><p> We present here some results from the numerical evolution of <br />spherically symmetric and axisymmetric spacetimes. Two basic aspects <br />were common in the cases we have treated: first, the field equations <br />are in the characteristic formulation, and second, we have employed <br />the spectral methods to solve the numerically the field equations. In <br />the spherical case black holes are produced as the result of the <br />collapse of scalar fields. The whole spectrum of black hole masses <br />which ranges from infinitesimal to large values are obtained after <br />varying the amplitude of the initial scalar field distribution. Then, <br />we have found strong numerical evidence that this spectrum is <br />described by a nonextensive distribution law. Concerning axisymmetric <br />spacetimes we have integrated the field equations of Robinson-Trautman <br />space times with a new and efficient code. We have applied the code to <br />describe in a simple scenario the non-frontal collision of two black <br />holes. Finally, a more realistic framework represented by the field <br />equations of the Bondi problem were considered. </p><p> </p><p>Place and time:</p><p>Physics Department meeting room, 2nd floor</p><p>17 Dec 2010 - 14:30 </p>