On GaussBonnet gravity in four dimensions Speaker(s): David Kubiznak
Abstract:
We comment on the recently introduced GaussBonnet gravity in four dimensions. We argue that it does not make sense to consider this theory to be defined by a set of D>4 solutions of the higherdimensional GaussBonnet gravity. We show that a welldefined D>4 limit of GaussBonnet Gravity is obtained generalizing a method employed by Mann and Ross to obtain a limit of the Einstein gravity in D=2 dimensions. This is a scalartensor theory of the Horndeski type obtained by dimensional reduction methods. By considering simple spacetimes beyond spherical symmetry (TaubNUT spaces) we show that the naive limit of the higherdimensional theory to four dimensions is not well defined and contrast the resultant metrics with the actual solutions of the new theory. Theory and solutions in lower dimensions will also be briefly discussed.
Date: 30/04/2020  1:00 pm
Series: Strong Gravity
