A Combinatorial Interpretation for Schreyer’s Tetragonal Invariants
نویسندگان
چکیده
Schreyer has proved that the graded Betti numbers of a canonical tetragonal curve are determined by two integers b1 and b2, associated to the curve through a certain geometric construction. In this article we prove that in the case of a smooth projective tetragonal curve on a toric surface, these integers have easy interpretations in terms of the Newton polygon of its defining Laurent polynomial. We can use this to prove an intrinsicness result on Newton polygons of small lattice width. MSC2010: Primary 14H45, Secondary 14M25
منابع مشابه
New Improvement in Interpretation of Gravity Gradient Tensor Data Using Eigenvalues and Invariants: An Application to Blatchford Lake, Northern Canada
Recently, interpretation of causative sources using components of the gravity gradient tensor (GGT) has had a rapid progress. Assuming N as the structural index, components of the gravity vector and gravity gradient tensor have a homogeneity degree of -N and - (N+1), respectively. In this paper, it is shown that the eigenvalues, the first and the second rotational invariants of the GGT (I1 and ...
متن کاملInvariance of the barycentric subdivision of a simplicial complex
In this paper we prove that a simplicial complex is determined uniquely up to isomorphism by its barycentric subdivision as well as its comparability graph. We also put together several algebraic, combinatorial and topological invariants of simplicial complexes.
متن کاملA combinatorial approach to hypermatrix algebra
We present a formulation of the Cayley-Hamilton theorem for hypermatrices in conjunction with the corresponding combinatorial interpretation. Finally we discuss how the formulation of the Cayley-Hamilton theorem for hyermatrices leads to new graph invariants which in some cases results in symmetry breakings among cospectral graphs.
متن کاملCombinatorial Invariants of Algebraic Hamiltonian Actions
To any Hamiltonian action of a reductive algebraic group G on a smooth irreducible symplectic variety X we associate certain combinatorial invariants: Cartan space, Weyl group, weight and root lattices. For cotangent bundles these invariants essentially coincide with those arising in the theory of equivarant embeddings. Using our approach we establish some properties of the latter invariants.
متن کاملTowards Hilbert ’ s 24 th Problem : Combinatorial Proof Invariants
Proofs Without Syntax [37] introduced polynomial-time checkable combinatorial proofs for classical propositional logic. This sequel approaches Hilbert’s 24 Problem with combinatorial proofs as abstract invariants for sequent calculus proofs, analogous to homotopy groups as abstract invariants for topological spaces. The paper lifts a simple, strongly normalising cut elimination from combinatori...
متن کامل