On separation theorems for subadditive and superadditive functionals

• Autorzy: Zbigniew Gajda , Zygfryd Kominek
• Języki publikacji: EN

Abstrakty

EN

We generalize the well known separation theorems for subadditive and superadditive functionals to some classes of not necessarily Abelian semigroups. We also consider the problem of supporting subadditive functionals by additive ones in the not necessarily commutative case. Our results are motivated by similar extensions of the Hyers stability theorem for the Cauchy functional equation. In this context the so-called weakly commutative and amenable semigroups appear naturally. The relations between these two classes of semigroups are discussed at the end of the paper.

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Studia Mathematica
• Rocznik: 1991
• Tom: 100
• Numer: 1
• Strony: 25-38

Daty

wydano

1991

otrzymano

1990-05-10

poprawiono

1990-07-20

poprawiono

1990-10-23

Twórcy

autor

Zbigniew Gajda

• Department of Mathematics, Silesian University, Bankowa 14, 40-007 Katowice, Poland

autor

Zygfryd Kominek

• Department of Mathematics, Silesian University, Bankowa 14, 40-007 Katowice, Poland

Bibliografia

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