Geodesic deviation, Raychaudhuri equation, Newtonian limit, and tidal forces in Weyl-type f(Q, T) gravity

Abstract We consider the geodesic deviation equation, describing relative accelerations of nearby particles, and Raychaudhuri giving evolution kinematical quantities associated with deformations (expansion, shear rotation) in Weyl-type f ( Q , T ) gravity, which non-metricity is represented standard Weyl form, fully determined by vector, while represents trace matter energy–momentum tensor. The effects geometry extra force induced non-metricity–matter coupling are explicitly taken into account. Newtonian limit theory investigated, generalized Poisson containing correction terms coming from geometry, coupling, derived. As a physical application equation modifications tidal forces, due to obtained weak-field approximation. motion test particles directly influenced gradients force, vector. concrete astrophysical example we obtain expression Roche (the orbital distance at satellite begins be tidally torn apart body it orbits) gravity.