caa a22 4500 445386193 CHVBK 20180317143033.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s10714-011-1244-0 doi (NATIONALLICENCE)springer-10.1007/s10714-011-1244-0 Ellis George Mathematics Department, University of Cape Town, Cape Town, South Africa aut Shear free solutions in general relativity theory [Elektronische Daten] [George Ellis] The Goldberg-Sachs theorem is an exact result on shear-free null geodesics in a vacuum spacetime. It is compared and contrasted with an exact result for pressure-free matter: shear-free flows cannot both expand and rotate. In both cases, the shear-free condition restricts the way distant matter can influence the local gravitational field. This leads to intriguing discontinuities in the relation of the General Relativity solutions to Newtonian solutions in the timelike case, and of the full theory to the linearised theory in the null case. Springer Science+Business Media, LLC, 2011 General relativity nationallicence Exact solutions nationallicence Shear-free fluid flows nationallicence Shear free null rays nationallicence Goldberg-Sachs theorem nationallicence General Relativity and Gravitation Springer US; http://www.springer-ny.com 43/12(2011-12-01), 3253-3268 0001-7701 43:12<3253 2011 43 10714 https://doi.org/10.1007/s10714-011-1244-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10714-011-1244-0 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Ellis George Mathematics Department, University of Cape Town, Cape Town, South Africa aut NATIONALLICENCE 773 0- General Relativity and Gravitation Springer US; http://www.springer-ny.com 43/12(2011-12-01), 3253-3268 0001-7701 43:12<3253 2011 43 10714 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer