TY - JOUR

T1 - Gordon and Kerr-Schild ansätze in massive and bimetric gravity

AU - Baccetti, Valentina

AU - Martin-Moruno, Prado

AU - Visser, Matt

PY - 2012

Y1 - 2012

N2 - We develop the "generalized Gordon ansatz" for the ghost-free versions of both massive and bimetric gravity, an ansatz which is general enough to include almost all spacetimes commonly considered to be physically interesting, and restricted enough to greatly simplify calculations. The ansatz allows explicit calculation of the matrix square root γ = √g -lf appearing as a central feature of the ghost-free analysis. In particular, this ansatz automatically allows us to write the effective stress-energy tensor as that corresponding to a perfect fluid. A qualitatively similar "generalized Kerr-Schild ansatz" can also be easily considered, now leading to an effective stress-energy tensor that corresponds to a null fluid. Cosmological implications are considered, as are consequences for black hole physics. Finally we have a few words to say concerning the null energy condition in the framework provided by these ansätze.

AB - We develop the "generalized Gordon ansatz" for the ghost-free versions of both massive and bimetric gravity, an ansatz which is general enough to include almost all spacetimes commonly considered to be physically interesting, and restricted enough to greatly simplify calculations. The ansatz allows explicit calculation of the matrix square root γ = √g -lf appearing as a central feature of the ghost-free analysis. In particular, this ansatz automatically allows us to write the effective stress-energy tensor as that corresponding to a perfect fluid. A qualitatively similar "generalized Kerr-Schild ansatz" can also be easily considered, now leading to an effective stress-energy tensor that corresponds to a null fluid. Cosmological implications are considered, as are consequences for black hole physics. Finally we have a few words to say concerning the null energy condition in the framework provided by these ansätze.

UR - http://www.scopus.com/inward/record.url?scp=84865734803&partnerID=8YFLogxK

U2 - 10.1007/JHEP08(2012)108

DO - 10.1007/JHEP08(2012)108

M3 - Article

AN - SCOPUS:84865734803

SN - 1126-6708

SP - 1

EP - 18

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

IS - 8

M1 - 108

ER -