2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/85324Neutron spin can be coupled to the Earth's rotating frequency. Once if the Earth's rotating frequency is time-dependent, then the neutron will acquire a Berry's topological phase (cyclic adiabatic geometric phase). So, a potential method to investigate the Earth's time-varying rotating frequency by measuring the phase difference between geometric phases of neutron spin polarized vertically down and up is proposed.1 page, LatexGeophysicstext