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arXiv · 0909.4962

Generalized polygons with non-discrete valuation defined by two-dimensional affine R-buildings

Koen Struyve·Hendrik Van Maldeghem
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Abstract

In this paper, we show that the building at infinity of a two-dimensional affine R-building is a generalized polygon endowed with a valuation satisfying some specific axioms. Specializing to the discrete case of affine buildings, this solves part of a long standing conjecture about affine buildings of type G~_2, and it reproves the results obtained mainly by the second author for types A~_2 and C~_2. The techniques are completely different from the ones employed in the discrete case, but they are considerably shorter, and general (i.e., independent of the type of the two-dimensional R-building).

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Koen Struyve, Hendrik Van Maldeghem. 2009-09-27. Generalized polygons with non-discrete valuation defined by two-dimensional affine R-buildings. https://arxiv.org/abs/0909.4962

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