English

Ideals in the convolution algebra of periodic distributions

Functional Analysis 2023-04-17 v1 Commutative Algebra Rings and Algebras

Abstract

The ring of periodic distributions on Rd{\mathbb{R}}^{\tt d} with usual addition and with convolution is considered. Via Fourier series expansions, this ring is isomorphic to the ring S(Zd){\mathcal{S}}'({\mathbb{Z}}^{\tt d}) of all maps f:ZdCf:{\mathbb{Z}}^{\tt d}\rightarrow \mathbb{C} of at most polynomial growth (i.e., there exist a real M>0M>0 and a nonnegative integer m{\tt m} such that for all n=(n1,,nd)Zd\mathbf{n}=({\tt n}_1,\cdots, {\tt n}_{\tt d})\in {\mathbb{Z}}^{\tt d}, f(n)M(1+n1++nd)m |f(\mathbf{n})|\leq M(1+|{\tt n}_1|+\cdots+|{\tt n}_{\tt d}|)^{\tt m}), with pointwise operations. It is shown that finitely generated ideals in S(Zd){\mathcal{S}}'({\mathbb{Z}}^{\tt d}) are principal, and ideal membership is characterised analytically. Calling an ideal in S(Zd){\mathcal{S}}'({\mathbb{Z}}^{\tt d}) fixed if there is a common index nZd\mathbf{n} \in {\mathbb{Z}}^{\tt d} where each member vanishes, the fixed maximal ideals are described, and it is shown that not all maximal ideals are fixed. It is shown that finitely generated proper prime ideals in S(Zd){\mathcal{S}}'({\mathbb{Z}}^{\tt d}) are fixed maximal ideals. The Krull dimension of S(Zd){\mathcal{S}}'({\mathbb{Z}}^{\tt d}) is proved to be infinite, while the weak Krull dimension is shown to be equal to 11.

Keywords

Cite

@article{arxiv.2304.07285,
  title  = {Ideals in the convolution algebra of periodic distributions},
  author = {Amol Sasane},
  journal= {arXiv preprint arXiv:2304.07285},
  year   = {2023}
}

Comments

12 pages. arXiv admin note: text overlap with arXiv:2303.05316