12 Answers votes newest views recent 4Fiction books about mathematicians? 0What out-of-print books would you like to see re-printed? 1Algebraic stacks from scratch 0Good introductory references on algebraic stacks? 12Justifying a theory by a seemingly unrelated example 3Why is Riemann-Roch an Index Problem? 3When are GIT quotients projective? 2Why and how are moduli spaces of (semi)stable vector bundles well-behaved? 3Ambiguous definition of “nerve of an open covering” on wikipedia? 0Definition of longest common subsequences 2Moduli spaces of vector bundles and stability conditions 0Reference for openness of stable locus of holomorphic family of vector bundles on a compact riemann surface.