3 papers
Physical nonviability of in the scalar-tensor representation
Jose Beltrán Jiménez, Alejandro Jiménez Cano, Tomi S. Koivisto
The authors demonstrate that the scalar‑tensor representation of f(Q) gravity inevitably contains a propagating ghost degree of freedom, confirming its physical non‑viability.
Cosmological Spacetimes with Sign-Changing Spatial Curvature and Topological Transitions
Gerardo GarcÃa-Moreno, Bert Janssen, Alejandro Jiménez Cano +3
Observational evidence, together with practical computations and modeling, supports a Euclidean spatial sector in the current cosmological model based on the FLRW metric. This, how…
A class of ghost-free theories in symmetric teleparallel geometry
Antonio G. Bello-Morales, Jose Beltrán Jiménez, Alejandro Jiménez Cano +2
Theories formulated in the arena of teleparallel geometries are generically plagued by ghost-like instabilities or other pathologies that are ultimately caused by the breaking of s…