Extremal problems in Minkowski space related to minimal networks

Swanepoel, K.

doi:10.1090/S0002-9939-96-03370-9

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Extremal problems in Minkowski space
related to minimal networks

Author: K. J. Swanepoel
Journal: Proc. Amer. Math. Soc. 124 (1996), 2513-2518
MSC (1991): Primary 52A40, 52A21, 49F10
MathSciNet review: 1327047
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Abstract: We solve the following problem of Z. Füredi, J. C. Lagarias and F. Morgan (1991): Is there an upper-bound polynomial in $n$ for the largest cardinality of a set $S$ of unit vectors in an $n$ -dimensional Minkowski space (or Banach space) such that the sum of any subset has norm less than 1? We prove that $|S|\leq 2n$ and that equality holds iff the space is linearly isometric to $\ell ^{n}_{\infty }$ , the space with an $n$ -cube as unit ball. We also remark on similar questions they raised that arose out of the study of singularities in length-minimizing networks in Minkowski spaces.

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