Cotangent Bundle to the Flag Variety - I
  We show that there is a ${SL_n}$-stable closed subset of an affine Schubert variety in the infinite dimensional Flag variety (associated to the Kac-Moody group ${\widehat{SL_n}}$) which is a natural compactification of the cotangent bundle to the finite-dimensional Flag variety ${{SL_n/B}}$. 
V. Lakshmibai, C.S. Seshadri, R. Singh
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