6533b85efe1ef96bd12bf512
RESEARCH PRODUCT
Ghosts in metric-affine higher order curvature gravity
Jose Beltrán JiménezAdrià Delhomsubject
PhysicsHigh Energy Physics - TheoryPhysics and Astronomy (miscellaneous)010308 nuclear & particles physicsFOS: Physical scienceslcsh:AstrophysicsGeneral Relativity and Quantum Cosmology (gr-qc)Invariant (physics)Curvature01 natural sciencesRotation formalisms in three dimensionsGeneral Relativity and Quantum CosmologyFormalism (philosophy of mathematics)Theoretical physicsHigh Energy Physics - Theory (hep-th)0103 physical scienceslcsh:QB460-466lcsh:QC770-798lcsh:Nuclear and particle physics. Atomic energy. RadioactivityAffine transformationProjective test010306 general physicsEngineering (miscellaneous)Ricci curvaturedescription
We disprove the widespread belief that higher order curvature theories of gravity in the metric-affine formalism are generally ghost-free. This is clarified by considering a sub-class of theories constructed only with the Ricci tensor and showing that the non-projectively invariant sector propagates ghost-like degrees of freedom. We also explain how these pathologies can be avoided either by imposing a projective symmetry or additional constraints in the gravity sector. Our results put forward that higher order curvature gravity theories generally remain pathological in the metric-affine (and hybrid) formalisms and highlight the key importance of the projective symmetry and/or additional constraints for their physical viability and, by extension, of general metric-affine theories.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2019-08-01 | European Physical Journal C: Particles and Fields |