Search for Small Violations of the Symmetrization Postulate for Spin-0 Particles

An accurate test of the symmetrization postulate of quantum mechanics has been performed on the spin-0 ${}^{16}\mathrm{O}$ nuclei, by looking for transitions in the ${\mathrm{CO}}_{2}$ spectra involving states which are antisymmetric in the exchange of the nuclei. Using high-sensitivity laser spectroscopy, a bound of $2.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$ has been set to a possible violation of such postulate, with an improvement of more than 2 orders of magnitude with respect to the previous limit.