THE NO-DEFECT CONJECTURE AND ITS IMPLICATIONS

When the topology of the universe is non-trivial, there exist constrai nts on the network of topological defects that may appear during a pha se transition in the early universe. Here we review the main results o f two recent papers by Uzan and Peter concerning topological defects i n a multiconnected universe: the no-defect conjecture, the evaluation of the redshift at which all the defects (if formed) have disappeared and the consequence on the cosmic microwave background.