  The Universe is a physical object. Physical objects have shapes and sizes.
General relativity is insufficient to describe the global shape and size of the
Universe: the Hilbert-Einstein equations only treat limiting quantities towards
an arbitrary point. Empirical work on measuring the shape and size of the
Universe (formally: the ``3-manifold of the spatial hypersurface at constant
cosmological time'', and, e.g. the ``injectivity diameter'' respectively) has
progressed significantly in the late 1980's and the 1990's, using observational
catalogues of galaxy clusters, of quasars and of the microwave background,
though the analyses are still hindered by simplifying (and often
observationally unsupported) assumptions. A review of the different
observational strategies and claimed constraints was presented at the meeting.
