Degenerate affine flag varieties and quiver Grassmannians (Q2071262)

In this paper, the author studies finite dimensional approximations to degenerate versions of affine flag varieties using quiver Grassmannians for cyclic quivers. He proves that they admit cellular decompositions parameterized by affine Dellac configurations. Moreover, he shows that their irreducible components are normal Cohen-Macaulay varieties with rational singularities. This paper is based on work by \textit{G. Cerulli Irelli} et al. [Algebra Number Theory 6, No. 1, 165--194 (2012; Zbl 1282.14083)] and on work by \textit{E. Feigin} et al. [Kyoto J. Math. 57, No. 2, 445--474 (2017; Zbl 1417.14006)].