Einstein's cosmic model of 1931 revisited: an analysis and translation of a forgotten model of the universe
Abstract
We present an analysis and translation of Einstein's 1931 paper "Zum kosmologischen Problem der allgemeinen Relativitätstheorie" or "On the cosmological problem of the general theory of relativity". In this littleknown paper, Einstein proposes a cosmic model in which the universe undergoes an expansion followed by a contraction, quite different to the monotonically expanding Einsteinde Sitter model of 1932. The paper offers many insights into Einstein's cosmology in the light of the first evidence for an expanding universe and we consider his views of issues such as the curvature of space, the cosmological constant, the singularity and the timespan of the expansion. A number of original findings concerning Einstein's 1931 model are presented. We find that Einstein's calculations of the present radius and matter density of the universe contain some anomalies: we suggest that his estimate of the age of the universe is based on a questionable calculation of Friedmann's: we find that the model is not periodic, contrary to what is often stated. A first English translation of Einstein's paper is included as an Appendix.
 Publication:

European Physical Journal H
 Pub Date:
 February 2014
 DOI:
 10.1140/epjh/e201340038x
 arXiv:
 arXiv:1312.2192
 Bibcode:
 2014EPJH...39...63O
 Keywords:

 Physics  History and Philosophy of Physics;
 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 Published in the European Physical Journal (H). The article includes a first English translation of Einstein's 1931 SAW paper and the discovery of an error in Einstein's calculation of the matter density of the universe. 30 pages, 2 figures