Abstract
Canonical analysis of a recently proposed curvature gravity model in establishes its pure, irreducibly fourth derivative, quadratic curvature limit as both ghost-free and power-counting UV finite, thereby maximally violating standard folklore. This limit is representative of a generic class whose kinetic terms are conformally invariant in any dimension, but it is unique in simultaneously avoiding the transverse-traceless graviton ghosts plaguing quadratic actions as well as double pole propagators in its other variables. While the two-term model is also unitary, its additional mode’s second-derivative nature forfeits finiteness.
- Received 28 April 2009
DOI:https://doi.org/10.1103/PhysRevLett.103.101302
©2009 American Physical Society