2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/179096We study the effects of a scalar field, coupled only to neutrinos, on oscillations among weak interaction current eigenstates. The effect of a real scalar field appears as effective masses for the neutrino mass eigenstates, the same for $\nbar$ as for $\n$. Under some conditions, this can lead to a vanishing of $δm^2$, giving rise to MSW-like effects. We discuss some examples and show that it is possible to resolve the apparent discrepancy in spectra required by r-process nucleosynthesis in the mantles of supernovae and by Solar neutrino solutions.9 pages, latex, 1 figureHigh Energy Physics - Phenomenologytext