Pointwise convergence on the rings of functions which are discontinuous on a set of measure zero

Abstract

Consider the ring ℳ∘ ( X , μ ) of functions which are discontinuous on a set of measure zero which is introduced and studied extensively in [2]. In this paper, we have introduced a ring B1 ( X , μ ) of functions which are pointwise limits of sequences of functions in ℳ∘ ( X , μ ) . We have studied various properties of zero sets, B1 ( X , μ ) -separated and B1 ( X , μ ) -embedded subsets of B1 ( X , μ ) and also established an analogous version of Urysohn's extension theorem. We have investigated a connection between ideals of B1 ( X , μ ) and ZB -filters on X. We have studied an analogue of Gelfand-Kolmogoroff theorem in our setting. We have defined real maximal ideals of B1 ( X , μ ) and established the result | ℛ M a x ( ℳ∘ ( X , μ ) ) | = | ℛ M a x ( B1 ( X , μ ) ) | , where ℛ M a x ( ℳ∘ ( X , μ ) ) and ℛ M a x ( B1 ( X , μ ) ) are the sets of all real maximal ideals of ℳ∘ ( X , μ ) and B1 ( X , μ ) respectively.

Keywords

• measure spaces
• complete measure
• real maximal ideal
• b1-separated
• zb -filters
• b1(x,μ)-compact space