Results 1 to 10 of about 3,105 (119)
Complex reflection groups and K3 surfaces I [PDF]
Épijournal de Géométrie Algébrique, 2021 We construct here many families of K3 surfaces that one can obtain as quotients of algebraic surfaces by some subgroups of the rank four complex reflection groups. We find in total 15 families with at worst $ADE$--singularities. In particular we classify
Cédric Bonnafé, Alessandra Sarti
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Le probl\`eme de la sch\'ematisation de Grothendieck revisit\'e [PDF]
Épijournal de Géométrie Algébrique, 2020 The objective of this work is to reconsider the schematization problem of [6], with a particular focus on the global case over Z. For this, we prove the conjecture [Conj. 2.3.6][15] which gives a formula for the homotopy groups of the schematization of a
Bertrand Toën
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Factorization of the Abel-Jacobi maps [PDF]
Épijournal de Géométrie Algébrique, 2021 As an application of the theory of Lawson homology and morphic cohomology, Walker proved that the Abel-Jacobi map factors through another regular homomorphism. In this note, we give a direct proof of the theorem.
Fumiaki Suzuki
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Explicit equations of the Cartwright-Steger surface [PDF]
Épijournal de Géométrie Algébrique, 2020 We construct explicit equations of Cartwright-Steger and related surfaces.
Lev A. Borisov, Sai-Kee Yeung
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The conjectures of Artin-Tate and Birch-Swinnerton-Dyer [PDF]
Épijournal de Géométrie Algébrique, 2022 We provide two proofs that the conjecture of Artin-Tate for a fibered surface is equivalent to the conjecture of Birch-Swinnerton-Dyer for the Jacobian of the generic fibre.
S. Lichtenbaum +2 more
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Serre-invariant stability conditions and Ulrich bundles on cubic threefolds [PDF]
Épijournal de Géométrie Algébrique, 2023 We prove a general criterion which ensures that a fractional Calabi--Yau category of dimension $\leq 2$ admits a unique Serre-invariant stability condition, up to the action of the universal cover of $\text{GL}^+_2(\mathbb{R})$.
Soheyla Feyzbakhsh, Laura Pertusi
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Families of stable 3-folds in positive characteristic [PDF]
Épijournal de Géométrie Algébrique, 2023 We show that flat families of stable 3-folds do not lead to proper moduli spaces in any characteristic $p>0$. As a byproduct, we obtain log canonical 4-fold pairs, whose log canonical centers are not weakly normal.
János Kollár
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Hilbert-Mumford stability on algebraic stacks and applications to $\mathcal{G}$-bundles on curves [PDF]
Épijournal de Géométrie Algébrique, 2018 In these notes we reformulate the classical Hilbert-Mumford criterion for GIT stability in terms of algebraic stacks, this was independently done by Halpern-Leinster.
Jochen Heinloth
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Stable rationality of higher dimensional conic bundles [PDF]
Épijournal de Géométrie Algébrique, 2018 We prove that a very general nonsingular conic bundle $X\rightarrow\mathbb{P}^{n-1}$ embedded in a projective vector bundle of rank $3$ over $\mathbb{P}^{n-1}$ is not stably rational if the anti-canonical divisor of $X$ is not ample and $n\geq 3$.
Hamid Ahmadinezhad, Takuzo Okada
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Exceptional collections on certain Hassett spaces [PDF]
Épijournal de Géométrie Algébrique, 2021 We construct an $S_2\times S_n$ invariant full exceptional collection on Hassett spaces of weighted stable rational curves with $n+2$ markings and weights $(\frac{1}{2}+\eta, \frac{1}{2}+\eta,\epsilon,\ldots,\epsilon)$, for ...
Ana-Maria Castravet, Jenia Tevelev
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