Results 41 to 50 of about 555 (183)
Local Factorization of Birational Maps
Advances in Mathematics, 1997 Inclusions of regular local rings \(R\subset S\) of dimension two with common quotient field have (according to a well known theorem of Zariski-Abhyankar) a simple structure, namely: \(R\subset S\) can be factored by a unique finite product of quadratic transforms. In dimension \(\geq 3\) the situation is a lot more complicated. In this sense Abhyankar
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Automorphism groups of P1$\mathbb {P}^1$‐bundles over geometrically ruled surfaces
Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.Abstract We classify the pairs (X,π)$(X,\pi)$, where π:X→S$\pi \colon X\rightarrow S$ is a P1$\mathbb {P}^1$‐bundle over a non‐rational geometrically ruled surface S$S$ and Aut∘(X)$\mathrm{Aut}^\circ (X)$ is relatively maximal, that is, maximal with respect to the inclusion in the group Bir(X/S)$\mathrm{Bir}(X/S)$.
Pascal Fong
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On the algebraic properties of difference approximations of Hamiltonian systems
Discrete and Continuous Models and Applied Computational ScienceIn this paper, we examine difference approximations for dynamic systems characterized by polynomial Hamiltonians, specifically focusing on cases where these approximations establish birational correspondences between the initial and final states of the ...
Lyubov O. Lapshenkova +2 more
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On the canonical bundle formula in positive characteristic
Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.Abstract Let f:X→Z$f:X\to Z$ be a fibration from a normal projective variety X$X$ of dimension n$n$ onto a normal curve Z$Z$ over a perfect field of characteristic p>2$p>2$. Let (X,B)$(X,B)$ be a dlt pair such that the induced pair on a general fibre is log canonical.
Marta Benozzo
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Birational Maps of X(1) into P2
Glasnik matematički, 2013 In this paper we study birational maps of modular curve X(1) attached to SL2(Z) into the projective plain P2. We prove that every curve of genus 0 and degree q in P2 can be uniformized by modular forms for SL2(Z) of weight 12q but not with modular forms of smaller weight, and that the corresponding uniformization can be chosen to be a birational ...
Muić, Goran, Mikoč, Damir
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The geometry of zonotopal algebras II: Orlik–Terao algebras and Schubert varieties
Proceedings of the London Mathematical Society, Volume 132, Issue 6, June 2026.Abstract Zonotopal algebras, introduced by Postnikov–Shapiro–Shapiro, Ardila–Postnikov, and Holtz–Ron, show up in many different contexts, including approximation theory, representation theory, Donaldson–Thomas theory, and hypertoric geometry. In the first half of this paper, we construct a perfect pairing between the internal zonotopal algebra of a ...
Colin Crowley, Nicholas Proudfoot
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Coulomb branch algebras via symplectic cohomology
Journal of Topology, Volume 19, Issue 2, June 2026.Abstract Let (M¯,ω)$(\bar{M}, \omega)$ be a compact symplectic manifold with convex boundary and c1(TM¯)=0$c_1(T\bar{M})=0$. Suppose that (M¯,ω)$(\bar{M}, \omega)$ is equipped with a convex Hamiltonian G$G$‐action for some connected, compact Lie group G$G$.
Eduardo González +2 more
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Symplectic Maps from Cluster Algebras
Symmetry, Integrability and Geometry: Methods and Applications, 2011 We consider nonlinear recurrences generated from the iteration of maps that arise from cluster algebras. More precisely, starting from a skew-symmetric integer matrix, or its corresponding quiver, one can define a set of mutation operations, as well as a
Allan P. Fordy, Andrew Hone
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On regularizable birational maps
, 2020 Bedford asked if there exists a birational self map $f$ of the complex projective plane such that for any automorphism $A$ of the complex projective plane $A\circ f$ is not conjugate to an automorphism. Blanc gave such a $f$ of degree $6$ and asked if there exists an example of smaller degree. In this article we give an example of degree $5$.
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On birational maps from cubic threefolds [PDF]
NWEJM, 2014 In the last version, the relation with the work of [CM13] has been developed and the fact that the open subset in the moduli space of curve is dense has been ...
Blanc, Jérémy, Lamy, Stéphane
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