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Physical Review Letters

Test of the linearity of quantum mechanics in optically pumped Hg201

P. K. Majumder, B. J. Venema, S. K. Lamoreaux, Blayne R. Heckel, E. Norval Fortson

Published Dec 10, 1990• 56 citations
Publisher

Abstract

Measurement of the free precession of nuclear spins in optically pumped ground-state $^{201}\mathrm{Hg}$ atoms has allowed a test of Weinberg's nonlinear generalization of quantum mechanics. Shifts among the three resolved precession frequencies in the spin-3/2 system were studied as a function of the projection of spin polarization along the precession axis. Our results set an upper limit on \ensuremath{\epsilon}, Weinberg's nonlinearity parameter, of \ensuremath{\Vert}\ensuremath{\epsilon}\ensuremath{\Vert}/2\ensuremath{\pi}\ensuremath{\Elzxh}3.8\ensuremath{\mu} Hz, which corresponds to 2.0\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}27}$ of the binding energy per nucleon. This is the most stringent such limit to date.

DOI
10.1103/physrevlett.65.2931

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