Brane worlds (Q2765190)

The theory of gravity on 3-branes with a focus on the codimension-one models, as a possible new paradigm for spacetime, is reviewed. A higher-dimensional version of the Lanczos-Israel matching conditions is derived. The need for the Gibbons-Hawking term in the action principle with codimension 1 hypersurfaces is shown. The Newtonian limit on thin branes is discussed in the framework of Arkani-Hamed, Dimopoulos and Dvali, in the Randall-Sundrum model and in the model of Dvali, Gabadadze and Porrati. The cosmological evolution of the 3-brane in the latter model may follow the standard Friedmann equation, which implies that one should rely on specifically \({\mathbf x}\)-dependent effects to observationally distinguish the Friedmann cosmology from the brane cosmology.