| Article | |
| Report number | arXiv:1407.4991 ; CERN-PH-TH-2014-132 ; CERN-PH-TH-2014-132 |
| Title | Nonderivative Modified Gravity: a Classification |
| Author(s) | Comelli, Denis (INFN, Ferrara ; CERN) ; Nesti, Fabrizio (Boskovic Inst., Zagreb ; GSSI, Aquila) ; Pilo, Luigi (L'Aquila U. ; Gran Sasso) |
| Publication | 2014-11-12 |
| Imprint | 18 Jul 2014 |
| Number of pages | 21 |
| Note | Comments: No comment No comment |
| In: | JCAP 11 (2014) 018 |
| DOI | 10.1088/1475-7516/2014/11/018 |
| Subject category | Particle Physics - Theory |
| Abstract | We analyze the theories of gravity modified by a generic nonderivative potential built from the metric, under the minimal requirement of unbroken spatial rotations. Using the canonical analysis, we classify the potentials $V$ according to the number of degrees of freedom (DoF) that propagate at the nonperturbative level. We then compare the nonperturbative results with the perturbative DoF propagating around Minkowski and FRW backgrounds. A generic $V$ implies 6 propagating DoF at the non-perturbative level, with a ghost on Minkowski background. There exist potentials which propagate 5 DoF, as already studied in previous works. Here, no $V$ with unbroken rotational invariance admitting 4 DoF is found. Theories with 3 DoF turn out to be strongly coupled on Minkowski background. Finally, potentials with only the 2 DoF of a massive graviton exist. Their effect on cosmology is simply equivalent to a cosmological constant. Potentials with 2 or 5 DoF and explicit time dependence appear to be a further viable possibility. |
| Copyright/License | preprint: © 2014-2024 CERN (License: CC-BY-3.0) publication: © 2014-2024 The Author(s) (License: CC-BY-3.0), sponsored by SCOAP³ |
Corresponding record in: Inspire
Record created 2014-07-21, last modified 2023-10-04
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