Gravitação holográfica

Abstract

In this work we will expose a new perspective on gravity, consequently on the dynamics of spacetime. We will present a standard treatment on the gravitational action and the conditions to hold in order to arrive on the field equations. Then we shall investigate a remarkable gravitational Lagrangean feature: even though the Lagrangean itself has second order derivatives on the metric, we can still arrive at second order field equations. After we show that imposing invariance by a special class of diffeomorphisms on the gravitational action, we can get the field equations when using surface term, rather than the bulk term as it is standard on literature. Then we show it is possibly only for pure gravity, and we discuss about it’s validity when matter is rigorously considered.