Symmetric Ideals and Invariant Hilbert Schemes

التفاصيل البيبلوغرافية
العنوان: Symmetric Ideals and Invariant Hilbert Schemes
المؤلفون: Debus, Sebastian, Kretschmer, Andreas
سنة النشر: 2024
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Algebraic Geometry, Mathematics - Commutative Algebra, Mathematics - Combinatorics, 14C05, 14L30, 05E14, 05E40
الوصف: A symmetric ideal is an ideal in a polynomial ring which is stable under all permutations of the variables. In this paper we initiate a global study of zero-dimensional symmetric ideals. By this we mean a geometric study of the invariant Hilbert schemes $\mathrm{Hilb}_{\rho}^{S_n}(\mathbb{C}^n)$ parametrizing symmetric subschemes of $\mathbb{C}^n$ whose coordinate rings, as $S_n$-modules, are isomorphic to a given representation $\rho$. In the case that $\rho = M^\lambda$ is a permutation module corresponding to certain special types of partitions $\lambda$ of $n$, we prove that $\mathrm{Hilb}_{\rho}^{S_n}(\mathbb{C}^n)$ is irreducible or even smooth. We also prove irreducibility whenever $\dim \rho \leq 2n$ and the invariant Hilbert scheme is non-empty. In this same range, we classify all homogeneous symmetric ideals and decide which of these define singular points of $\mathrm{Hilb}_{\rho}^{S_n}(\mathbb{C}^n)$. A central tool is the combinatorial theory of higher Specht polynomials.
Comment: Comments welcome!
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2404.15240
رقم الأكسشن: edsarx.2404.15240
قاعدة البيانات: arXiv