Ferrer, F.Nowakowski, M. [UNESP]2014-05-272014-05-271999-04-01Physical Review D - Particles, Fields, Gravitation and Cosmology, v. 59, n. 7, p. 1-7, 1999.0556-2821http://hdl.handle.net/11449/65754In certain mild extensions of the standard model, spin-independent long range forces can arise by exchange of two very light pseudoscalar spin-0 bosons. In particular, we have in mind models in which these bosons do not have direct tree level couplings to ordinary fermions. Using the dispersion theoretical method, we find a 1/r3 behavior of the potential for the exchange of very light pseudoscalars and a 1/r7 dependence if the pseudoscalars are true massless Goldstone bosons. ©1999 The American Physical Society.1-7engArtigo10.1103/PhysRevD.59.075009WOS:000079466900048Acesso aberto2-s2.0-166443747092-s2.0-16644374709.pdf