2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/205718The elasticity difference tensor, used in [1] to describe elasticity properties of a continuous medium filling a space-time, is here analysed from the point of view of the space-time connection. Principal directions associated with this tensor are compared with eigendirections of the material metric. Examples concerning spherically symmetric and axially symmetric space-times are then presented.17 pagesGeneral Relativity and Quantum Cosmologytext