Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2606.06849

Parabolic second-order tangent sets of semialgebraic sets and applications to polynomial optimization

Cong Trinh Le
View original source ↗Read source document ↗Export metadata ↓

Abstract

We study parabolic second-order tangent sets of semialgebraic sets and their use in local polynomial optimization. For a basic closed semialgebraic feasible set, we compare the true parabolic tangent set with the algebraic second-order linearized set determined by gradients and Hessians of the active constraints. Under directional rank stability and semialgebraic parabolic arc-realizability, the outer, inner, and arc-generated tangent sets coincide with this algebraic model. Exact formulas are obtained for smooth hypersurfaces, regular complete intersections, smooth inequality systems, and stratified semialgebraic sets. These formulas yield algebraically checkable second-order necessary conditions and sufficient conditions for quadratic growth in polynomial optimization. Examples show how the theory detects curvature, flatness, branch dependence, and the failure of ordinary quadratic scaling.

Explore related subjects

math.AG

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Cong Trinh Le. 2026-06-05. Parabolic second-order tangent sets of semialgebraic sets and applications to polynomial optimization. https://arxiv.org/abs/2606.06849

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Perverse Euler Characteristics of Hermitian Locally Symmetric Spaces

We prove that finite-volume locally Hermitian symmetric spaces of noncompact type have nonnegative perverse Euler characteristics. To show this, we obtain a nefness result for the logarithmic cotangent bundle of a smooth toroidal compactification. Combining this with a positivity criterion for Euler characteristics of perverse sheaves, we deduce the nonnegativity result. We further prove that the inequality is strict for perverse sheaves with full support. As applications, we get nonnegativity results for perverse Euler characteristics on various moduli spaces.

math.AG↗
arXiv2026

Coupled Pklt Tuples and Varieties of Pklt Type

We introduce asymptotic multiplier ideal sheaves and log canonical thresholds associated with tuples of pseudoeffective divisors on a projective klt pair. We prove that the threshold of a coupled potentially klt tuple is computed by a quasi-monomial valuation. For varieties of potentially klt type, we prove that every big divisor admits a birational Zariski decomposition with semiample positive part. We also prove finite generation of multisection rings of big divisors and give a criterion for a variety of potentially klt type to be a Mori dream space.

math.AG↗
arXiv2026

Graded Betti numbers of general curves of large degree

Let $C$ be a smooth projective complex curve of genus $g$ and gonality $k$, and $L$ be a very ample line bundle on $C$. When $L$ has sufficiently large degree, the vanishing and nonvanishing of the Koszul cohomology groups $K_{p,q}(C,L)$ have been determined previously, but the exact values of the graded Betti numbers $\kappa_{p,q}(C, L)$ remain largely unknown. In this paper, we give explicit closed formulas for all graded Betti numbers $\kappa_{p,q}(C, L)$ when the Brill--Noether locus $W_k^1(C)$ has the expected dimension and $H^1(C, L \otimes \omega_C^{-1})=0$. Consequently, we determine the complete Betti table for a general curve when $\deg L \geq 4g-3$ or when $\deg L \geq 3g-3$ and $L$ is general. We also explicitly compute the Boij--S\"{o}derberg coefficient of the section ring $R(C, L)$ governing asymptotic purity, and show eventual monotonicity of the remaining coefficients: they decrease for hyperelliptic curves and increase under a natural generic reducedness assumption on the relevant Brill--Noether loci.

math.AG↗