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Using the new extension of the zero-divisor graph $\widetilde{\Gamma}(R)$ introduced in \cite{Groupe}, we give an approach of the diameter of $\Gamma(R)$ and $\Gamma(R[X])$ other than given in \cite{Lucas} thus we give a complete…

Commutative Algebra · Mathematics 2018-12-21 A. Cherrabi , H. Essannouni , E. Jabbouri , A. Ouadfel

In a recent paper by a superset of the authors it was proved that for every primitive 3-constrained space $\Gamma$ of finite diameter $\delta$ from Cherlin's catalogue of metrically homogeneous graphs, there exists a finite family $\mathcal…

Combinatorics · Mathematics 2025-11-03 Jan Hubička , Michael Kompatscher , Matěj Konečný

In this paper we discuss an obstruction to the integral Hodge conjecture, which arises from certain behavior of vanishing cycles. This allows us to construct new counter-examples to the integral Hodge conjecture. One typical such…

Algebraic Geometry · Mathematics 2019-01-23 Mingmin Shen

For a del Pezzo surface of degree $\geq 3$, we compute the oscillatory integral for its mirror Landau-Ginzburg model in the sense of Gross-Hacking-Keel [Mark Gross, Paul Hacking, and Sean Keel, "Mirror symmetry for log Calabi-Yau surfaces…

Algebraic Geometry · Mathematics 2023-09-06 Bohan Fang , Junxiao Wang , Yan Zhou

In the following text for arbitrary $X$ with at least two elements, nonempty set $\Gamma$ and self-map $\varphi:\Gamma\to\Gamma$ we prove the set-theoretical entropy of generalized shift $\sigma_\varphi:X^\Gamma\to X^\Gamma$…

Dynamical Systems · Mathematics 2018-06-12 Zahra Nili Ahmadabadi , Fatemah Ayatollah Zadeh Shirazi

Let $\Gamma$ be a finite group acting linearly on $\C^n$, freely outside the origin, and let $N$ be the number of conjugacy classes of $\Gamma$ minus one. A construction of Kronheimer of moduli spaces $X_\zeta$ of translation-invariant…

alg-geom · Mathematics 2008-02-03 Alexander V Sardo Infirri

A celebrated but non-effective theorem of Tibor Gallai states that for any finite set $A$ of $\Z^n$ and for any finite number of colors $c$ there is a minimal $m$ such that no coloring of the finite $m^n$-grid can avoid that a homothetic…

Combinatorics · Mathematics 2025-12-30 Bogdan Dumitru , Mihai Prunescu

We study when a smooth variety $X$, embedded diagonally in its Cartesian square, is the zero scheme of a section of a vector bundle of rank $\dim(X)$ on $X\times X$. We call this the diagonal property (D). It was known that it holds for all…

Algebraic Geometry · Mathematics 2007-05-23 Piotr Pragacz , Vasudevan Srinivas , Vishwambhar Pati

For each odd $m \geq 3$ we completely solve the problem of when an $m$-cycle system of order $u$ can be embedded in an $m$-cycle system of order $v$, barring a finite number of possible exceptions. In cases where $u$ is large compared to…

Combinatorics · Mathematics 2015-06-15 Daniel Horsley , Rosalind A. Hoyte

We prove that only finitely many Shimura curves can have gonality bounded by a given number, and we study the computability of this finite set. Motivated by the relation between hyperellipticity (that is, gonality 2) and the vanishing of…

Number Theory · Mathematics 2025-10-10 Congling Qiu

Given an embedded smooth projective variety Y in CP^n, we show how the existence of a hypersurface with high multiplicity along Y, but of relatively low degree and log canonical near Y implies vanishing of higher cohomology for certain…

alg-geom · Mathematics 2008-02-03 Aaron Bertram

A curve $\gamma$ in a Riemannian manifold $M$ is three-dimensional if its torsion (signed second curvature function) is well-defined and all higher-order curvatures vanish identically. In particular, when $\gamma$ lies on an oriented…

Differential Geometry · Mathematics 2023-08-25 Matteo Raffaelli

Suppose that $n\neq p^k$ and $n\neq 2p^k$ for all $k$ and all primes $p$. We prove that for any Hausdorff compactum $X$ with a free action of the symmetric group $\mathfrak S_n$ there exists an $\mathfrak S_n$-equivariant map $X \to…

Geometric Topology · Mathematics 2021-05-10 Sergey Avvakumov , Sergey Kudrya

In this note we are going to prove that if we have a fibration of smooth projective varieties $X\to S$ over a surface $S$ such that $X$ is of dimension four and that the geometric generic fiber has finite dimensional motive and the first…

Algebraic Geometry · Mathematics 2021-03-11 Kalyan Banerjee

The "zero in the spectrum conjecture" asserted (in its strongest form) that for any manifold M zero should be in the l2-spectrum of the Laplacian (on forms) of the universal covering of M, i.e. that at least one (unreduced) L2-cohomology…

K-Theory and Homology · Mathematics 2009-03-24 Nigel Higson , John Roe , Thomas Schick

Associated to an algebraic curve $X$, there are two canonically constructed homologically trivial algebraic $1$-cycles, the Ceresa cycle in the Jacobian of $X$, and the Gross-Kudla-Schoen modified diagonal cycle in the triple product $X…

Algebraic Geometry · Mathematics 2025-06-19 Matt Kerr , Wanlin Li , Congling Qiu , Tonghai Yang

A number of new sufficient conditions for generalized cycles (large cycles including Hamilton and dominating cycles as special cases) in an arbitrary $k$-connected graph $(k=1,2,...)$ and new lower bounds for the circumference (the length…

Combinatorics · Mathematics 2023-05-24 Zhora Nikoghosyan

A colored Gaussian graphical model is a linear concentration model in which equalities among the concentrations are specified by a coloring of an underlying graph. Marigliano and Davies conjectured that every linear binomial that appears in…

Combinatorics · Mathematics 2025-07-01 Hannah Göbel , Pratik Misra

Moduli spaces of stable objects in the derived category of a $K3$ surface provide a large class of holomorphic symplectic varieties. In this paper, we study the interplay between Chern classes of stable objects and zero-cycles on…

Algebraic Geometry · Mathematics 2019-12-04 Junliang Shen , Qizheng Yin , Xiaolei Zhao

Let X be a geometrically smooth n-dimensional projective algebraic complex hypersurface in P^{n+1}(C). Using Green-Griffiths jets, we establish the existence of nonzero global algebraic differential equations that must be satisfied by every…

Algebraic Geometry · Mathematics 2014-06-19 Joel Merker