OPEN SUPERMEMBRANES IN 11 DIMENSIONS

We consider open supermembranes in an eleven dimensional background. W e show that, in a flat space-time, the worldvolume action is kappa-sym metric and has global space-time supersymmetry if space-time has even dimensional topological defects where the membrane can end. An example of such topological defects is provided by the space-time with bounda ries considered by Horava and Witten. In that case the world-volume ac tion has reparametrisation anomalies whose cancellation requires the i nclusion of a current algebra on the boundaries of the membrane. The r ole of kappa-anomalies in a general background is discussed. The tensi on of the membrane is related to the eleven dimensional gravitational constant with the aid of the Green-Schwarz mechanism allowing a consis tency check of M-theory. (C) 1997 Elsevier Science B.V.