Abstract
In this paper we study the interior angle sums of geodesic triangles in \(\mathbf {Nil}\) geometry and prove that these can be larger, equal or less than \(\pi \). We use for the computations the projective model of \(\mathbf {Nil}\) introduced by Molnár (Beitr. Algebra Geom. 38(2):261–288, 1997).
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Szirmai, J. \(\mathbf {Nil}\) Geodesic Triangles and Their Interior Angle Sums. Bull Braz Math Soc, New Series 49, 761–773 (2018). https://doi.org/10.1007/s00574-018-0077-9
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DOI: https://doi.org/10.1007/s00574-018-0077-9