TY - JOUR

T1 - Fully covariant van Dam-Veltman-Zakharov discontinuity, and absence thereof

AU - Porrati, M.

N1 - Funding Information:
We should like to thank G. Dvali, A. Lue, and C. Deffayet for interesting comments. This work is supported in part by NSF grant PHY-0070787.

PY - 2002/5/16

Y1 - 2002/5/16

N2 - In both old and recent literature, it has been argued that the celebrated van Dam-Veltman-Zakharov (vDVZ) discontinuity of massive gravity is an artifact due to linearization of the true equations of motion. In this Letter, we investigate that claim. First, we exhibit an explicit - albeit somewhat arbitrary - fully covariant set of equations of motion that, upon linearization, reduce to the standard Pauli-Fierz equations. We show that the vDVZ discontinuity still persists in that non-linear, covariant theory. Then, we restrict our attention to a particular system that consistently incorporates massive gravity: the Dvali-Gabadadze-Porrati (DGP) model. DGP is fully covariant and does not share the arbitrariness and imperfections of our previous covariantization, and its linearization exhibits a vDVZ discontinuity. Nevertheless, we explicitly show that the discontinuity does disappear in the fully covariant theory, and we explain the reason for this phenomenon.

AB - In both old and recent literature, it has been argued that the celebrated van Dam-Veltman-Zakharov (vDVZ) discontinuity of massive gravity is an artifact due to linearization of the true equations of motion. In this Letter, we investigate that claim. First, we exhibit an explicit - albeit somewhat arbitrary - fully covariant set of equations of motion that, upon linearization, reduce to the standard Pauli-Fierz equations. We show that the vDVZ discontinuity still persists in that non-linear, covariant theory. Then, we restrict our attention to a particular system that consistently incorporates massive gravity: the Dvali-Gabadadze-Porrati (DGP) model. DGP is fully covariant and does not share the arbitrariness and imperfections of our previous covariantization, and its linearization exhibits a vDVZ discontinuity. Nevertheless, we explicitly show that the discontinuity does disappear in the fully covariant theory, and we explain the reason for this phenomenon.

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U2 - 10.1016/S0370-2693(02)01656-8

DO - 10.1016/S0370-2693(02)01656-8

M3 - Article

AN - SCOPUS:0037118158

VL - 534

SP - 209

EP - 215

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

IS - 1-4

ER -