Short-Range Forces Due to Lorentz-Symmetry Violation: Going Beyond The Standard Yukawa Parametrization*

Short-range modifications to Newtonian gravity arising from spacetime-symmetry breaking are studied in this work. The first non-perturbative, i.e., to all orders in coefficients for Lorentz-symmetry breaking, are constructed in the Newtonian limit. We make use of the generic symmetry-breaking terms modifying the gravity sector and examine the isotropic coefficient limit. In which we derive the coefficients in the weak gravity limit using Green function methods. The results show new kinds of force law corrections, going beyond the standard Yukawa parameterization. Further, there are ranges of the values of the coefficients that could make the resulting forces large compared to the Newtonian prediction at short distances. Experimental signals are discussed for typical test mass arrangements.