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Related papers: Clifford index for reduced curves

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In this paper we investigate how the short-time Fourier transform can be extended in a Clifford setting. We prove some of the main properties of the Clifford short-time Fourier transform such as the orthogonality relation, the…

Classical Analysis and ODEs · Mathematics 2021-11-17 Antonino De Martino

Let X be a curve over a number field K with genus g>=2, $\pp$ a prime of O_K over an unramified rational prime p>2r, J the Jacobian of X, r=rank J(K), and $\scrX$ a regular proper model of X at $\pp$. Suppose r<g. We prove that…

Number Theory · Mathematics 2013-01-28 Eric Katz , David Zureick-Brown

We extend the theory of Koszul modules to the bi-graded case, and prove a vanishing theorem that allows us to show that the Canonical Ribbon Conjecture of Bayer and Eisenbud holds over a field of characteristic zero or at least equal to the…

Commutative Algebra · Mathematics 2022-01-27 Claudiu Raicu , Steven V Sam

Brill-Noether theory of curves has played a crucial role in the study of curves and their moduli since the 19th century, and has been extensively studied by several authors. Clifford's theorem provides a starting point in determining the…

Algebraic Geometry · Mathematics 2025-10-21 Neelarnab Raha

Categorical resolutions of singularities are a replacement of resolution of singularities within the realm of triangulated categories. They allow the study of the derived category of a singular variety $X$ via a triangulated category that…

Algebraic Geometry · Mathematics 2025-12-05 Nicolás Vilches

In this paper we prove a relative version of the classical Mumford-Newstead theorem for a family of smooth curves degenerating to a reducible curve with a simple node. We also prove a Torelli-type theorem by showing that certain moduli…

Algebraic Geometry · Mathematics 2016-05-17 Suratno Basu

We describe derivations of the Clifford algebra of a nondegenerate quadratic form on a countable dimensional vector space over an algebraically closed field of characteristic not equal to $2$. We also construct an algebraic automorphism of…

Rings and Algebras · Mathematics 2024-08-15 Oksana Bezushchak

We prove that the Clifford spectrum associated to three 2 by 2 matrices is nonempty. The structure of Clifford is described in terms "moving" level curves. We discuss some implication of a conjecture formulated for arbitrary size n by n of…

Functional Analysis · Mathematics 2026-02-18 Alexander Cerjan , Vasile Lauric , Terry A. Loring

We show, among other things, that in most cases the gonality of a subcanonical curve in projective-three space is computable by multisecants.

Algebraic Geometry · Mathematics 2007-05-23 Ph. Ellia , D. Franco

We give an inductive construction for irreducible Clifford systems on Euclidean vector spaces. We then discuss how this notion can be adapted to Riemannian manifolds, and outline some developments in octonionic geometry.

Differential Geometry · Mathematics 2016-09-13 Maurizio Parton , Paolo Piccinni , Victor Vuletescu

Let $C$ be an algebraic curve defined by a sufficiently generic bivariate Laurent polynomial with given Newton polygon $\Delta$. It is classical that the geometric genus of $C$ equals the number of lattice points in the interior of…

Algebraic Geometry · Mathematics 2016-04-05 Wouter Castryck , Filip Cools

We prove a sharp relative Clifford inequality for relatively special divisors on varieties fibered by curves. It generalizes the classical Clifford inequality about a single curve to a family of curves. It yields a geographical inequality…

Algebraic Geometry · Mathematics 2018-03-08 Tong Zhang

We give examples of curves of arbitrarily high Clifford index such that the Prym map is not injective at any of their \'etale double covers.

Algebraic Geometry · Mathematics 2010-01-21 E. Izadi , H. Lange

These are lecture notes for a course on the theory of Clifford algebras, with special emphasis on their wide range of applications in mathematics and physics. Clifford algebra is introduced both through a conventional tensor algebra…

Mathematical Physics · Physics 2009-07-31 Douglas Lundholm , Lars Svensson

We introduce a notion of matrix valued Gram decompositions for correlation matrices whose study is motivated by quantum information theory. We show that for extremal correlations, the matrices in such a factorization generate a Clifford…

Optimization and Control · Mathematics 2018-10-01 Anupam Prakash , Antonios Varvitsiotis

We give lower bounds for the degree of the discriminant with respect to y of separable polynomials f in K[x,y] over an algebraically closed field of characteristic zero. Depending on the invariants involved in the lower bound, we give a…

Algebraic Geometry · Mathematics 2015-07-07 Denis Simon , Martin Weimann

Let $f: S\longrightarrow B$ be a non-trivial fibration from a complex projective smooth surface $S$ to a smooth curve $B$ of genus $b$. Let $c_f$ the Clifford index of the generic fibre $F$ of $f$. In [arXiv:1401.7502v4] it is proved that…

Algebraic Geometry · Mathematics 2017-10-03 Filippo Francesco Favale , Juan Carlos Naranjo , Gian Pietro Pirola

It shown that if a vector space carries commuting actions of two Clifford algebras, then the quadratic monomials using generators from either Clifford algebra determine a spinor representation of an orthogonal Lie algebra. Examples of this…

Mathematical Physics · Physics 2024-10-29 John W. Barrett

In the traditional approaches to Clifford algebras, the Clifford product is evaluated by recursive application of the product of a one-vector (span of the generators) on homogeneous i.e. sums of decomposable (Grassmann), multivectors and…

Mathematical Physics · Physics 2007-05-23 Bertfried Fauser

To any nodal curve $C$ is associated the degree class group, a combinatorial invariant which plays an important role in the compactification of the generalised Jacobian of $C$ and in the construction of the N\'eron model of the Picard…

Algebraic Geometry · Mathematics 2008-08-18 Simone Busonero , Margarida Melo , Lidia Stoppino