Projections in the convex hull of two isometries of absolutely continuous function spaces

Positivity - Tập 25 - Trang 791-799 - 2020
Maliheh Hosseini1
1Faculty of Mathematics, K. N. Toosi University of Technology, Tehran, Iran

Tóm tắt

In this paper we provide a complete description of projections in the convex hull of two surjective linear isometries (carrying a weighted composition operator form) on absolutely continuous function space AC(X, E), where X is a compact subset of $$\mathbb R$$ with at least two points and E is a strictly convex normed space. Among the consequences of the main result, it is shown that generalized bi-circular projections are the only projections on AC(X) expressed as the convex combination of two surjective linear isometries, and an affirmative answer is given to the question in Botelho and Jamison (Canad Math Bull 53:398–403, 2010) for such spaces.

Tài liệu tham khảo

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