Homotopy extension property for multi-valued functions

Abstract

In this study, we introduce some well-known definitions and properties for multi-valued functions. We present new definitions such as, m-retraction, m-section, m-homeomorphism, m-HEP and reducible function. We give a new result on the relation between multi-homotopy groups and m-homeomorphism. We also deal with some properties of m-HEP.

Keywords

• multi-valued function
• m-retraction
• m-homeomorphism
• homotopy extension property