# Fortnightly links (144)

Haoyang Guo, Sanal Shivaprasad, Dylan Spence, Yueqiao Wu: Boundedness of semistable sheaves is another expository paper to be included in SPEC, which stands for Stacks Project Expository Collection (mentioned in the previous fortnightly links). It's a really nice exposition to prove that moduli of semistable torsion-free sheaves are bounded.

Marcello Bernardara, Enrico Fatighenti, Laurent Manivel, Fabio Tanturri: Fano fourfolds of K3 type is a super cool paper describing Fano 4-folds using the geometry of homogeneous varieties, and in particular zooms in on 64 families whose Hodge theory and derived categories should be particularly interesting and related to K3 surfaces. I'm a big fan of such methods, and it's great to see this combination of computational techniques, classical algebraic geometry and modern questions!

Julian Wykowski, Travis Schedler: An investigation into Lie algebra representations obtained from regular holonomic D-modules is a nice expository article on D-modules, explaining Beilinson–Bernstein localisation for $\mathbb{P}^1$ from a topological point-of-view. If you're like me and you're getting started on learning more about D-modules, this is a nice visual introduction.