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This is a survey paper on derived symplectic geometry, that will appear as a chapter contribution to the book "New Spaces for Mathematics and Physics", edited by Mathieu Anel and Gabriel Catren. Our goal is to explain how derived stacks can…

Symplectic Geometry · Mathematics 2021-04-08 Damien Calaque

This is the first part of the article we promised at the end of [FOOO13, Section 1]. We discuss the foundation of the virtual fundamental chain and cycle technique, especially its version appeared in [FOn] and also in [FOOO4, Section A1,…

Symplectic Geometry · Mathematics 2015-03-27 Kenji Fukaya , Yong-Geun Oh , Hiroshi Ohta , Kaoru Ono

This work studies $t$-structures for the derived category of quasi-coherent sheaves on a quasi-compact quasi-separated algebraic stack. Specifically, using Thomason filtrations, we classify those $t$-structures which are generated by…

Algebraic Geometry · Mathematics 2025-07-04 Pat Lank

For a certain class of real analytic varieties with Lie group actions we develop a theory of (free-monodromic) tilting sheaves, and apply it to flag varieties stratified by real group orbits. For quasi-split real groups, we construct a…

Algebraic Geometry · Mathematics 2025-09-17 Andrei Ionov , Zhiwei Yun

We show in this paper that in the context of graded Lie algebras, all cuspidal character sheaves arise from a nearby-cycle construction followed by a Fourier--Sato transform in a very specific manner. Combined with results of the last two…

Representation Theory · Mathematics 2025-12-29 Wille Liu , Cheng-Chiang Tsai , Kari Vilonen , Ting Xue

Recently, Oh and Thomas constructed algebraic virtual cycles for moduli spaces of sheaves on Calabi-Yau 4-folds. The purpose of this paper is to provide a virtual pullback formula between these Oh-Thomas virtual cycles. We find a natural…

Algebraic Geometry · Mathematics 2021-10-08 Hyeonjun Park

Let $X$ be a topologically stratified space, $p$ be any perversity on $X$, and $k$ be a field. We show that the category of $p$-perverse sheaves on $X$, constructible with respect to the stratification and with coefficients in $k$, is…

Representation Theory · Mathematics 2020-07-08 Alessio Cipriani , Jon Woolf

It is usually not straightforward to work with the category of perverse sheaves on a variety using only its definition as a heart of a $t$-structure. In this paper, the category of perverse sheaves on a smooth toric variety with its orbit…

Algebraic Geometry · Mathematics 2024-12-30 Sergey Guminov

We introduce, on a topological space X, a class of stacks of abelian categories we call "stacks of type P." This class of stacks includes the stack of perverse sheaves (of any perversity, constructible with respect to a fixed…

Representation Theory · Mathematics 2008-01-22 David Treumann

Despite the progress in cross-domain few-shot learning, a model pre-trained with DINO combined with a prototypical classifier outperforms the latest SOTA methods. A crucial limitation that needs to be overcome is that updating too many…

Computer Vision and Pattern Recognition · Computer Science 2025-11-19 Naeem Paeedeh , Mahardhika Pratama , Imam Mustafa Kamal , Wolfgang Mayer , Jimmy Cao , Ryszard Kowlczyk

Let $k$ be a field of characteristic $0$ endowed with a complex embedding $\sigma: k \hookrightarrow \mathbb{C}$. In this paper we complete the construction of the six functor formalism on perverse Nori motives over quasi-projective…

Algebraic Geometry · Mathematics 2026-02-11 Luca Terenzi

The constructions of the virtual Euler (or moduli) cycles and their properties are explained and developed systematically in the general abstract settings.

Symplectic Geometry · Mathematics 2007-07-08 Guangcun Lu , Gang Tian

This article is based on my lecture notes from summer schools at the Universities of Utah (June 2007) and Warwick (September 2007). We provide an introduction to explicit methods in the study of moduli spaces of quiver representations and…

Algebraic Geometry · Mathematics 2008-07-15 Alastair Craw

We use Donaldson hypersurfaces to construct pseudo-cycles which define Gromov-Witten invariants for any symplectic manifold which agree with the invariants in the cases where transversality could be achieved by perturbing the almost complex…

Symplectic Geometry · Mathematics 2008-04-17 Kai Cieliebak , Klaus Mohnke

We define bivariant algebraic K-theory and bivariant derived Chow on the homotopy category of derived schemes over a smooth base. The orientation on the latter corresponds to virtual Gysin homomorphisms. We then provide a morphism between…

Algebraic Geometry · Mathematics 2012-09-03 Parker Lowrey , Timo Schürg

We develop a theory of complex Kuranishi structures on projective schemes. These are sufficiently rigid to be equivalent to weak perfect obstruction theories, but sufficiently flexible to admit global complex Kuranishi charts. We apply the…

Algebraic Geometry · Mathematics 2024-03-05 Jeongseok Oh , Richard P. Thomas

We introduce semi-perfect obstruction theory of a Deligne-Mumford stack $X$ consisting of local perfect obstruction theories with weak comparisons on overlaps. We show that semi-perfect obstruction theory shares similar properties with…

Algebraic Geometry · Mathematics 2011-06-21 Huai-liang Chang , Jun Li

We generalize the construction of a moduli space of semistable pairs parametrizing isomorphism classes of morphisms from a fixed coherent sheaf to any sheaf with fixed Hilbert polynomial under a notion of stability to the case of projective…

Algebraic Geometry · Mathematics 2024-04-09 Yijie Lin

Our main result establishes functorial desingularization of noetherian quasi-excellent schemes over $\bfQ$ with ordered boundaries. A functorial embedded desingularization of quasi-excellent schemes of characteristic zero is deduced.…

Algebraic Geometry · Mathematics 2017-02-22 Michael Temkin

We use quantum and Floer homology to construct (partial) quasi-morphisms on the universal cover of the group of compactly supported Hamiltonian diffeomorphisms for a certain class of non-closed strongly semi-positive symplectic manifolds…

Symplectic Geometry · Mathematics 2016-05-10 Sergei Lanzat