dorsal/arxiv
View SchemaStructure and Decomposition of Deltoids in Abelian Groups
| Authors | Mohsen Aliabadi, Jozsef Losonczy |
|---|---|
| Categories | |
| ArXiv ID | 2601.09774vv1 |
| URL | https://arxiv.org/abs/2601.09774 |
| License | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
Abstract
Deltoids provide a natural framework for studying defective (partial) matchings in abelian groups, and we develop both structure and existence results in this setting. Given finite subsets $A$ and $B$ of an abelian group $G$, a matching is a bijection $f:A\to B$ such that $af(a)\notin A$ for all $a\in A$, a definition motivated by the study of canonical forms for symmetric tensors. We provide necessary and sufficient conditions for the existence of a partial matching with any prescribed defect, and then describe the minimal unavoidable defect for a pair $(A,B)$. We also define and examine a defective version of Chowla sets in the matching context. We prove a structure theorem identifying obstructions to the existence of partial matchings with small defect. Finally, within the deltoid setup, we establish max-min results on the partitioning of $A$ and $B$ into left- and right-admissible sets. Our tools mix results from transversal theory with ideas from additive number theory.
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"abstract": "Deltoids provide a natural framework for studying defective (partial) matchings in abelian groups, and we develop both structure and existence results in this setting. Given finite subsets $A$ and $B$ of an abelian group $G$, a matching is a bijection $f:A\\to B$ such that $af(a)\\notin A$ for all $a\\in A$, a definition motivated by the study of canonical forms for symmetric tensors. We provide necessary and sufficient conditions for the existence of a partial matching with any prescribed defect, and then describe the minimal unavoidable defect for a pair $(A,B)$. We also define and examine a defective version of Chowla sets in the matching context. We prove a structure theorem identifying obstructions to the existence of partial matchings with small defect. Finally, within the deltoid setup, we establish max-min results on the partitioning of $A$ and $B$ into left- and right-admissible sets. Our tools mix results from transversal theory with ideas from additive number theory.",
"arxiv_id": "2601.09774",
"authors": [
"Mohsen Aliabadi",
"Jozsef Losonczy"
],
"categories": [
"math.CO"
],
"license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
"title": "Structure and Decomposition of Deltoids in Abelian Groups",
"url": "https://arxiv.org/abs/2601.09774",
"version": "v1"
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