2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/132857We comment on the interpretation of absolute rotation measurements with superfluids, which involve the Sagnac effect. This effect, first observed in rotating optical interferometers, has now been seen in a host of different physical systems, ranging from atomic clocks to electrons, neutrons, atomic beams, ... We show that the time-honored explanation of this effect based on general relativity provides a common explanation for all these systems, including superfluids, in contradistinction with the views expressed in a recent review article.Letter to the Editors of Uspheki Fisiki Nauk - 4 pagesGeneral Relativity and Quantum CosmologyOther Condensed Mattertext