UPPER AND LOWER COMPLETELY CONTINUOUS MULTIFUNCTIONS
J. K. KOHLI(1) and C. P. ARYA(2)
1. Department of Mathematics, Hindu College, University of Delhi, Delhi 110007, INDIA e-mail: jk_kohli@ yahoo.co.in 2. ISSA/DRDO, Metcalfe House, Delhi 110054, INDIA. e-mail: carya28@ gmail.com
Abstract
The notion of complete continuity of functions (Kyungpook Math. J. 14(1974), 131-143) is extended to the realm of multifunctions. Basic properties of upper (lower) completely continuous multifunctions are studied and their place in the hierarchy of variants of con-tinuity of multifunctions is elaborated. Examples are included to reflect upon the distinc-tiveness of upper (lower) complete continuity of multifunctions from that of other vari-ants of continuity of multifunctions which already exist in the literature. Interplay be-tween topological properties and completely continuous multifunctions is considered.