Abstract
Let C(S)and C(T) denote the sup-normed Banach spaces of real- or complex-valued continuous functions on the compact Hausdorff spaces S and T, respectively. A linear map A∶C(T)→C(S) is calledseparating if when two functions x and y from C(T) have disjoint cozero sets then so do Ax and Ay. In the spirit of [3] and [4], we show that separating maps are automatically continuous in some important cases (Theorems 2.4 and 2.5). If a separating map is continuous, then it must be a continuous multiple of a composition map (Theorem 2.2). If A is injective, separating and detaching (Def. 2.4) then S and T are homeomorphic (Theorem 2.1).
Similar content being viewed by others
References
ABRAMOVIC, Y: Multiplicative representations of disjointness preserving operators, Indag. Math.45, 265–279 (1983)
ABRAMOVIC, Y., VEKSLER, A., and KOLDUNOV, V.: On operators preserving disjointness, Soviet Math. Dokl.20, 1089–1093 (1979)
ALBRECHT, E. and NEUMANN, M.: Automatic continuity of generalized local linear operators, Manuscripta Math.32, 263–294 (1980)
ALBRECHT, E. and NEUMANN, M.: Automatic continuity for operators of local type. Lecture Notes in Mathematics 975, 342–355, Berlin-Heidelberg-New York: Springer 1985
AMIR, D.: On isomorphisms of continuous function spaces, Israel J. Math.3, 205–210, (1965)
ARENDT, W.: Spectral properties of Lamperti operators, Indiana Univ. Math. J.32, 199–215 (1983)
BACHMAN, G.: Elements of abstract harmonic analysis. New York: Academic Press 1964
BECKENSTEIN, E. and NARICI, L.: A nonarchimedean Stone-Banach theorem, Proc. A. M. S.100, 242–246 (1987)
BECKENSTEIN, E. and NARICI, L.: Automatic continuity of certain linear isomorphisms, Acad. Roy. Belg. Bull. cl. sci. (5) Bruxelles73, 191–200 (1987)
CAMBERN, M.: On some isomorphisms with small bound, Proc. A. M. S.18, 1062–1066 (1967)
COHEN, H. B.: A bound-two isomorphism between C(X) Banach spaces, Proc. A. M. S.50, 215–217 (1975)
DE PAGTER, B.: A note on disjointness preserving operators, Proc. A. M. S.90, 543–549 (1984)
JAROSZ, K.: Automatic continuity of separating linear isomorphisms, to appear
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Beckenstein, E., Narici, L. & Todd, A.R. Automatic continuity of linear maps on spaces of continuous functions. Manuscripta Math 62, 257–275 (1988). https://doi.org/10.1007/BF01246833
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF01246833