Abstract
We introduce the Néron–Severi Lie algebra of a Soergel module and we determine it for a large class of Schubert varieties. This is achieved by investigating which Soergel modules admit a tensor decomposition. We also use the Néron–Severi Lie algebra to provide an easy proof of the well-known fact that a Schubert variety is rationally smooth if and only if its Betti numbers satisfy Poincaré duality.
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PATIMO, L. THE NÉRON–SEVERI LIE ALGEBRA OF A SOERGEL MODULE. Transformation Groups 23, 1063–1089 (2018). https://doi.org/10.1007/s00031-017-9448-3
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DOI: https://doi.org/10.1007/s00031-017-9448-3