Evidence for the Existence of Fractional Charge on Matter

We present results of a superconducting magnetic levitation experiment which provide evidence for the existence of fractional charge on matter. Three niobium balls heat-treated on a tungsten substrate were found to have residual charges of $(+0.337\ifmmode\pm\else\textpm\fi{}0.009)e$, $(\ensuremath{-}0.001\ifmmode\pm\else\textpm\fi{}0.025)e$, and $(\ensuremath{-}0.331\ifmmode\pm\else\textpm\fi{}0.070)e$. All five niobium balls heat-treated on a niobium substrate had residual charges near zero.