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On the self-length of two-dimensional Banach spaces

Published online by Cambridge University Press:  17 April 2009

B. Chalmers
Affiliation:
Department of Mathematics, University of California, Riverside CA 92521, United States of America
C. Franchetti
Affiliation:
Department of Mathematics, University of California, Riverside CA 92521, United States of America
M. Giaquinta
Affiliation:
Departmento di Matematica Applicata, Università di Firenze, 50139 Firenze, Italy
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The aim of this paper is to prove the following result: if X is a 2-dimensional symmetric real Banach space, then its self-length is greater than or equal to 2π. Moreover, the minimum value 2π is uniquely attained (up to isometries) by euclidean space.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1996

References

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