2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/129144Even though the concepts of time and space are basic concepts of physics, they have not been vouchsafed a constructive definition. As to space, this is no wonder because a correct notion of space cannot be formed in the frame of the existing physical paradigm. However, a definition of time can be given on the basis of the simple principle that each physical magnitude constitutes a feature of some physical carrier (Costa, 1987). This article deals with identifying that carrier for the feature "time". Finally this article affirms that because of the lack of a definition of time some physical experiments have been erroneously interpreted as signs of time dilation.5 pages, v2: added one referenceGeneral Physicstext