Proceedings of the American Mathematical Society

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ISSN 1088-6826(e) ISSN 0002-9939(p)

On orthogonally exponential and orthogonally additive mappings

Author(s): Janusz Brzdek
Journal: Proc. Amer. Math. Soc. 125 (1997), 2127-2132.
MSC (1991): Primary 39B52
MathSciNet review: 1376751
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Abstract: Let $E$ be a real inner product space, $(F,+)$ an abelian $\sigma$ -bounded topological group, and $K$ a discrete subgroup of $F$ . It is proved that (under suitable assumptions on $E)$ the Christensen and Baire measurable orthogonally additive functions $g\colon E\to F/K$ have particular selections. In consequence, descriptions of measurable orthogonally exponential complex functionals on $E$ are obtained.

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