Since force is transformed via: F'x= Fx ; F'y= Fy/ ϒ; F'z=Fz/ ϒ (F' is the force related to the moving frame, F is the force on the rest frame and ϒ=1/√1-v2/c2 ). I expect that G (Gravitational constant) will be transformed between moving and rest frame in order to satisfy force transformation since F=-Gm1m2/r2 Can you please refer me to a paper or text book on that specific topic? It is posable to see that substituting the mass Lorentz transformation m=moϒ and Lorentz-FitzGerald's contraction - ro/ϒ without applying a transformation on G, do not settle the force to get the force transformation like. Instead it gets F'=-Gm1m2 ϒ3/r2. Namely F'=F ϒ3. Can you please refer me to a paper or text book on that specific topic?