Abstract
The equation of motion for massive particles in modified theories of gravity is derived. By considering an explicit coupling between an arbitrary function of the scalar curvature, , and the Lagrangian density of matter, it is shown that an extra force arises. This extra force is orthogonal to the four-velocity and the corresponding acceleration law is obtained in the weak-field limit. Connections with MOND and with the Pioneer anomaly are further discussed.
- Received 18 April 2007
DOI:https://doi.org/10.1103/PhysRevD.75.104016
©2007 American Physical Society