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Mathematics Preprint PDF DOI

Ulrich bundles with $c_2(\mathcal E)^2=0$ and connectedness of Ulrich subvarieties

Valerio Buttinelli, Angelo Felice Lopez, Roberto Vacca · 2026

We give an almost complete classification of Ulrich bundles $\mathcal E$ with $c_2(\mathcal E)^2=0$ on a variety $X$ of dimension $n \ge 4$. Moreover, we show that there are strong constraints on the …

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Mathematics Preprint PDF DOI

Maximally nodal sextic surfaces and linear determinantal representations

Yonghwa Cho · 2026

We prove that every maximally nodal sextic surface\,(with 65 nodes) $X \subset \mathbb{P}_{\mathbb{C}}^3$ contains a symmetric half-even set of nodes of cardinality 35. It follows that the associated …

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AI & Data Science Preprint PDF DOI

Last-Iterate Convergence of Randomized Kaczmarz and SGD with Greedy Step Size

Micha{l} Derezinski, Xiaoyu Dong · 2026

We study last-iterate convergence of SGD with greedy step size over smooth quadratics in the interpolation regime, a setting which captures the classical Randomized Kaczmarz algorithm as well as other…

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Mathematics Preprint PDF DOI

Stability of syzygy bundles of Ulrich bundles

Rosa M. Miro-Roig · 2026

Let X be either a smooth K3 surface or a smooth Fano variety (i.e. $-K_X$ is ample) of dimension $n$ and index $i_X> n-3$ and let E be an initialized Ulrich bundle on X. In this paper, we show that th…

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Mathematics Preprint PDF DOI

Relation between Anderson Generating Functions and Weil Pairing

Chuangqiang Hu, Yixuan Ou-Yang · 2026

The existence of the Weil pairing for Drinfeld modules was proved by van~der~Heiden using the Anderson $t$-motive. Papikian's note provided the explicit formula for the rank-two Weil pairing that avoi…

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Mathematics Preprint PDF DOI

On relative Ulrich bundles and generalized Clifford algebras

Soham Mondal, Anindya Mukherjee · 2026

Let $X$ be a smooth projective scheme and $E$ a vector bundle on $X$. For a relative hypersurface $Y_f \subset \mathbb{P}(E)$ of degree $d$ defined by a global section $f$, we establish a functorial e…

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Engineering Preprint PDF DOI

Data-driven generalized perimeter control: Z\"urich case study

Alessio Rimoldi, Carlo Cenedese, Alberto Padoan, Florian Dorfler, John Lygeros · 2026

Urban traffic congestion is a key challenge for the development of modern cities, requiring advanced control techniques to optimize existing infrastructures usage. Despite the extensive availability o…

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AI & Data Science Preprint PDF DOI

One-Shot Individual Claims Reserving

Ronald Richman, Mario V. Wuthrich · 2026

Individual claims reserving has not yet become established in actuarial practice. We attribute this to the absence of a satisfactory methodology: existing approaches tend to be either overly complex o…

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Mathematics Preprint PDF DOI

Ulrich bundles on smooth toric threefolds with Picard number $2$

Debojyoti Bhattacharya, Francesco Malaspina · 2026

In this paper, we study Ulrich bundles on smooth toric threefolds with Picard number$~2$, namely $\mathbb P(\mathcal O_{\mathbb P^{2}}(a_0) \oplus \mathcal O_{\mathbb P^{2}}(a_1))$. We construct resol…

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Mathematics Preprint PDF DOI

Celebrating Women in Mathematics

Diana T. Stoeva · 2026

This paper was motivated by the worldwide May 12 initiative that aims to celebrate, encourage, and inspire women in mathematics. It presents in short how the May 12 initiative has arisen, what are som…

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Mathematics Preprint PDF DOI

Failing to keep the balance: explicit formulae and topological recursion for leaky Hurwitz numbers

Marvin Anas Hahn, Reinier Kramer · 2026

Recently a new family of enumerative invariants called leaky Hurwitz numbers was introduced by Cavalieri-Markwig-Ranganathan in the context of logarithmic intersection theory. They admit an interpreta…

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Earth & Environmental Sciences Preprint PDF DOI

Analysis of Karin and Koronis2 asteroid families: new findings and challenges

David Vokrouhlicky, David Nesvorny, William F. Bottke · 2026

We use our home catalog of the asteroid proper elements to study the Karin family. The hierarchical clustering method provides formal identification with 3,863 members, but this set also includes obje…

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Mathematics Preprint PDF DOI

Modules of minimal multiplicity over one-dimensional Cohen-Macaulay local rings

Ela Celikbas, Olgur Celikbas, Naoki Endo, Shinya Kumashiro · 2026

We study finitely generated modules of minimal multiplicity, a notion introduced by Puthenpurakal that extends the classical concept of minimal multiplicity from rings to modules. Our main result char…

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Physics Preprint PDF DOI

Calculating Feynman diagrams with matrix product states

Xavier Waintal · 2026

This text reviews, hopefully in a pedagogical manner, a series of work on the automatic calculations of Feynman diagrams in the context of quantum nanoelectronics (Keldysh formalism) with an applicati…

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Mathematics Preprint PDF DOI

Ulrich Sheaves on the Hilbert Square of K3 and Abelian Surfaces

Anindya Mukherjee, Pabitra Barik · 2026

We prove the existence of Ulrich sheaves on the Hilbert scheme of two points on a polarized K3 surface or an abelian surface. The construction proceeds by descending Ulrich bundles on the surface to t…

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Mathematics Preprint PDF DOI

On the triviality of direct image of vector bundles

Indranil Biswas, Jagadish Pine · 2026

Let $\pi\,:\, X \,\longrightarrow\, Y$ be a finite morphism of smooth projective varieties defined over an algebraically closed field of characteristic zero. We study the necessary and sufficient crit…

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AI & Data Science Preprint PDF DOI

Simulated Annealing Enhances Theory-of-Mind Reasoning in Autoregressive Language Models

Xucong Hu, Jian-Qiao Zhu · 2026

Autoregressive language models are next-token predictors and have been criticized for only optimizing surface plausibility (i.e., local coherence) rather than maintaining correct latent-state represen…

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Physics Preprint PDF DOI

Comments on Baryon Transition Form Factors

Christoph Hanhart, Maxim Mai, Ulf-G. Mei{ss}ner, Deborah Ronchen · 2026

We discuss in rather general terms the properties of space-like baryon transition form factors. In particular, we argue why these are necessarily complex-valued, what can be deduced from the respectiv…

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Computer Science Preprint PDF DOI

A New Tool to Find Lightweight (And, Xor) Implementations of Quadratic Vectorial Boolean Functions up to Dimension 9

Marie Bolzer (LORIA, CNRS, UL), Sebastien Duval (LORIA, CNRS, UL), Marine Minier (LORIA, CNRS, UL) · 2026

The problem of finding a minimal circuit to implement a given function is one of the oldest in electronics. It is known to be NP-hard. Still, many tools exist to find sub-optimal circuits to implement…

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Mathematics Preprint PDF DOI

On the Ulrichness of twisted syzygies and dual syzygies bundles

H. Torres Lopez, Alexis G. Zamora · 2026

Given a projective variety $X$ and a very ample line bundle $\mathcal{L}$ on $X$, we classify for which $X$ and $\mathcal{L}$ the twisted syzygies and twisted dual syzygies bundles are Ulrich with res…

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