Electrostatic self-force in (2+1)-dimensional cosmological gravity

Point sources in (2+1)-dimensional gravity are conical singularities that modify the global curvature of the space giving rise to selfinteraction effects on classical fields. In this work we study the electrostatic self-interaction of a point charge in the presence of point masses in (2+1)-dimensional gravity with a cosmological constant Λ. Exact expressions are obtained for the self-force on the charge in both Λ < 0 and Λ > 0 cases, which correspond to locally hyperbolic and spherical spaces, respectivelly. Both results, in the limit Λ → 0, coincide with the well-known flat space case. PACS numbers: 04.40.Nr, 41.20.Cv, 98.80.Cq