Proceedings of the American Mathematical Society

The ratio of the length of the unit circle to the area of the unit disc in Minkowski planes

Author(s): Zokhrab Mustafaev
Journal: Proc. Amer. Math. Soc. 133 (2005), 1231-1237.
MSC (2000): Primary 52A10, 52A40
Posted: September 16, 2004
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Abstract: In their paper ``An Introduction to Finsler Geometry,'' J. C. Alvarez and C. Duran asked if there are other Minkowski planes besides the Euclidean for which the ratio of the Minkowski length of the unit ``circle'' to the Holmes-Thompson area of the unit disc equals 2. In this paper we show that this ratio is greater than 2, and that the ratio 2 is achieved only for Minkowski planes that are affine equivalent to the Euclidean plane. In other words, the ratio is 2 only when the unit ``circle'' is an ellipse.

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Retrieve articles in Proceedings of the American Mathematical Society with MSC (2000): 52A10, 52A40

Zokhrab Mustafaev
Affiliation: Department of Mathematics and Computer Science, 1212 Williams Hall, Ithaca College, Ithaca, New York 14850
Email: zmustafaev@ithaca.edu

DOI: 10.1090/S0002-9939-04-07662-2
PII: S 0002-9939(04)07662-2
Received by editor(s): October 28, 2003
Received by editor(s) in revised form: December 15, 2003
Posted: September 16, 2004
Communicated by: Jon G. Wolfson
Copyright of article: Copyright 2004, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.

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