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Stable Andrews-Curtis trivialization of AK(3) revisited. A case study using automated deduction 对稳定的Andrews-Curtis AK(3)琐琐化进行了重新审视。使用自动推理的案例研究
Pub Date : 2025-10-13 DOI: 10.1016/j.jaca.2025.100041
Alexei Lisitsa
Recent work by Shehper et al. (2024) [13] proposed that the well-known Akbulut–Kirby presentation AK(3) is stably Andrews–Curtis (AC) equivalent to the trivial presentation, based on a reduction to a previously studied presentation P. In this paper, we present an independently obtained reduction of AK(3) to P, using a fully automated theorem proving approach. Subsequent to our initial submission, it has emerged that the earlier theoretical claim about the stable AC-trivializability of P—on which the Shehper et al. result relied—was based on an incorrect theorem, and thus the status of AK(3) remains unresolved. While this paper does not establish the stable AC-triviality of AK(3), it contributes a reproducible and verifiable case study in the use of automated reasoning to analyze deep problems in combinatorial group theory. We conclude by suggesting future directions for computational exploration of stable AC-transformations.
Shehper等人(2024)[13]最近的工作提出,基于对先前研究的表示P的约简,著名的Akbulut-Kirby表示AK(3)与平凡表示稳定地Andrews-Curtis (AC)等价。在本文中,我们使用全自动定理证明方法,提出了一个独立获得的AK(3)到P的约简。在我们最初的提交之后,我们发现早先关于稳定ac的理论主张——p的可琐碎性(Shehper等人的结果基于此)是基于一个不正确的定理,因此AK(3)的地位仍未得到解决。虽然本文没有建立AK(3)的稳定ac -平凡性,但它为使用自动推理分析组合群论中的深层问题提供了一个可重复和可验证的案例研究。最后,我们提出了稳定交流变换计算探索的未来方向。
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引用次数: 0
Machine learning mutation-acyclicity of quivers 机器学习突变-颤振的不周期性
Pub Date : 2025-09-01 DOI: 10.1016/j.jaca.2025.100040
Kymani T.K. Armstrong-Williams , Edward Hirst , Blake Jackson , Kyu-Hwan Lee
Machine learning (ML) has emerged as a powerful tool in mathematical research in recent years. This paper applies ML techniques to the study of quivers—a type of directed multigraph with significant relevance in algebra, combinatorics, computer science, and mathematical physics. Specifically, we focus on the challenging problem of determining the mutation-acyclicity of a quiver on 4 vertices, a property that is pivotal since mutation-acyclicity is often a necessary condition for theorems involving path algebras and cluster algebras. Although this classification is known for quivers with at most 3 vertices, little is known about quivers on more than 3 vertices. We give a computer-assisted proof of a theorem to prove that mutation-acyclicity is decidable for quivers on 4 vertices with edge weight at most 2. By leveraging neural networks (NNs) and support vector machines (SVMs), we then accurately classify more general 4-vertex quivers as mutation-acyclic or non-mutation-acyclic. Our results demonstrate that ML models can efficiently detect mutation-acyclicity, providing a promising computational approach to this combinatorial problem, from which the trained SVM equation provides a starting point to guide future theoretical development.
近年来,机器学习(ML)已成为数学研究中的一个强大工具。本文将机器学习技术应用于颤栗的研究,颤栗是一种与代数、组合学、计算机科学和数学物理有重要关联的有向多图。具体来说,我们专注于确定4个顶点上颤振的突变-不环性这一具有挑战性的问题,这是一个关键的性质,因为突变-不环性通常是涉及路径代数和簇代数的定理的必要条件。虽然这种分类对于最多3个顶点的箭囊是已知的,但对于超过3个顶点的箭囊却知之甚少。对于边权不超过2的4个顶点上的颤振,给出了突变-不环性可判定的一个定理的计算机辅助证明。通过利用神经网络(nn)和支持向量机(svm),我们准确地将更一般的4顶点颤振分类为突变-无环或非突变-无环。我们的研究结果表明,ML模型可以有效地检测突变-非周期性,为这一组合问题提供了一种有前途的计算方法,由此训练的SVM方程为指导未来的理论发展提供了一个起点。
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引用次数: 0
Computing quadratic subfields of number fields 计算数字域的二次子域
Pub Date : 2025-07-23 DOI: 10.1016/j.jaca.2025.100039
Andreas-Stephan Elsenhans , Jürgen Klüners
Given a number field, it is an important question in algorithmic number theory to determine all its subfields. If the search is restricted to abelian subfields, we can try to determine them by using class field theory. For this, it is necessary to know the ramified primes. We show that the ramified primes of the subfield can be computed efficiently. Using this information, we give algorithms to determine all quadratic and cyclic cubic subfields of the initial field. The approach generalises to cyclic subfields of prime degree. In the case of quadratic subfields, our approach is much faster than other methods.
给定一个数域,如何确定其所有子域是算法数论中的一个重要问题。如果搜索仅限于阿贝尔子域,我们可以尝试使用类场论来确定它们。为此,有必要知道派生素数。我们证明了子域的分支素数可以有效地计算。利用这些信息,给出了确定初始域的所有二次子域和循环三次子域的算法。该方法推广到素数次的循环子域。在二次子域的情况下,我们的方法比其他方法快得多。
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引用次数: 0
A 3-skeleton for a classifying space for the symmetric group 对称群分类空间的3-骨架
Pub Date : 2025-06-23 DOI: 10.1016/j.jaca.2025.100038
Matthew B. Day , Trevor Nakamura
We construct a 3-dimensional cell complex that is the 3-skeleton for an Eilenberg–MacLane classifying space for the symmetric group Sn. Our complex starts with the presentation for Sn with n1 adjacent transpositions with squaring, commuting, and braid relations, and adds seven classes of 3-cells that fill in certain 2-spheres bounded by these relations. We use a rewriting system and a combinatorial method of K. Brown to prove the correctness of our construction. Our main application is a computation of the second cohomology of Sn in certain twisted coefficient modules; we use this computation in a companion paper to study splitting of extensions related to braid groups. As another application, we give a concrete description of the third homology of Sn with untwisted coefficients in Z.
我们构造了一个三维细胞复合体,它是对称群Sn的Eilenberg-MacLane分类空间的3-骨架。我们的复合体从Sn的n−1相邻转置的平方,交换和编织关系开始,并添加了7类3-细胞,这些3-细胞填充在以这些关系为界的特定2-球体中。我们用一个改写系统和K. Brown的组合方法来证明我们构造的正确性。我们的主要应用是计算某些扭曲系数模中Sn的二次上同调;我们在另一篇论文中使用这种计算方法来研究与辫状群相关的扩展的分裂。作为另一个应用,我们给出了Sn在Z中具有未扭系数的第三同调的具体描述。
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引用次数: 0
An algorithm to compute the Hausdorff dimension of regular branch groups 正则分支群的Hausdorff维数计算算法
Pub Date : 2025-06-19 DOI: 10.1016/j.jaca.2025.100037
Jorge Fariña-Asategui
An explicit algorithm is given for the computation of the Hausdorff dimension of the closure of a regular branch group in terms of an arbitrary branch structure. We implement this algorithm in GAP and apply it to a family of GGS-groups acting on the 4-adic tree.
给出了一种计算任意分支结构下正则分支群闭包的Hausdorff维数的显式算法。我们在GAP中实现了该算法,并将其应用于作用于四进树的一组ggs群。
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引用次数: 0
Nested fifth root radical identities from elliptic curves 椭圆曲线的嵌套五根根恒等式
Pub Date : 2025-03-01 DOI: 10.1016/j.jaca.2025.100032
Joseph Tonien
Ramanujan discovered the following elegant identity involving cube roots:m4(m2n)3+n4m+n3=±13((4m+n)23+4(m2n)(4m+n)32(m2n)23).
The goal of this paper is to derive nested fifth root radical identities in the form ofP1Q15+P2Q25=p1q15+p2q25+p3q35+p4q45+p5q55. We show that these identities can be derived from a specific family of elliptic curves. Furthermore, we include the SageMath code for computing these expressions.
拉马努金发现了一个简洁的立方根等式:m4(m−2n)3+n4m+n3=±13((4m+n)23+4(m−2n)(4m+n)3−2(m−2n)23)。本文的目标是推导出嵌套的五根根恒等式,其形式为p1q15+ P2Q25=p1q15+ P2Q25 +p3q35+p4q45+p5q55。我们证明了这些恒等式可以从特定的椭圆曲线族中导出。此外,我们还包含了用于计算这些表达式的SageMath代码。
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引用次数: 0
Ideals of generic forms 一般形式的理想
Pub Date : 2025-03-01 DOI: 10.1016/j.jaca.2025.100033
Ralf Fröberg
We determine the Hilbert series of some classes of ideals generated by generic forms of degree two and three, and investigate the difference to the Hilbert series of ideals generated by powers of linear generic forms of the corresponding degrees.
我们确定了由二阶和三次一般形式生成的若干类理想的希尔伯特级数,并研究了它们与由相应次的线性一般形式幂生成的希尔伯特级数的区别。
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引用次数: 0
Listing words in free groups 在自由组中列出单词
Pub Date : 2025-03-01 DOI: 10.1016/j.jaca.2025.100034
Colin Ramsay
Lists of equivalence classes of words under rotation or rotation plus reversal (i.e., necklaces and bracelets) have many uses, and efficient algorithms for generating these lists exist. In combinatorial group theory elements of a group are typically written as words in the generators and their inverses, and necklaces and bracelets correspond to conjugacy classes and relators respectively. We present algorithms to generate lists of freely and cyclically reduced necklaces and bracelets in free groups. Experimental evidence suggests that these algorithms are CAT – that is, they run in constant amortized time.
在旋转或旋转加反转(即,项链和手镯)下的等效类的单词列表有许多用途,并且存在生成这些列表的有效算法。在组合群论中,群的元素通常在生成器及其逆中写成单词,项链和手镯分别对应于共轭类和关系类。我们提出算法,以产生自由和循环约简项链和手镯在自由组列表。实验证据表明这些算法是CAT -也就是说,它们在常数平摊时间内运行。
{"title":"Listing words in free groups","authors":"Colin Ramsay","doi":"10.1016/j.jaca.2025.100034","DOIUrl":"10.1016/j.jaca.2025.100034","url":null,"abstract":"<div><div>Lists of equivalence classes of words under rotation or rotation plus reversal (i.e., necklaces and bracelets) have many uses, and efficient algorithms for generating these lists exist. In combinatorial group theory elements of a group are typically written as words in the generators and their inverses, and necklaces and bracelets correspond to conjugacy classes and relators respectively. We present algorithms to generate lists of freely and cyclically reduced necklaces and bracelets in free groups. Experimental evidence suggests that these algorithms are CAT – that is, they run in constant amortized time.</div></div>","PeriodicalId":100767,"journal":{"name":"Journal of Computational Algebra","volume":"13 ","pages":"Article 100034"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144190158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Computational and theoretical aspects of rational parametrization of generalized tubular surfaces 广义管状曲面合理参数化的计算与理论研究
Pub Date : 2025-03-01 DOI: 10.1016/j.jaca.2025.100030
J. William Hoffman , Haohao Wang
This paper consists of two components - a computational part and a theoretical part. The former targets the computer-aided geometric design of tubular surfaces. The latter focuses on the algebraic geometry of a family of conic curves. At the application level, we provide a straightforward and easy to implement computational algorithm to rationally parametrize generalized real tubular surfaces via moving lines. We discover that syzygies, i.e., moving lines, can be calculated directly from a given implicit equation of a projective conic. Specifically, we describe two linear polynomial vectors in 3-space whose entries are formulated in terms of the coefficients of the given implicit equation of the conic. We then prove that these two vectors are, in fact, a μ-basis, the generators for the syzygy module of the given conic, and furnish the rational parametrization of the given conic. At the theoretical level, we first briefly review the classical projection method for a rational parametrization of a generic non-degenerate conic. This is compared to the syzygy method, i.e., moving lines. We conclude the paper with an illustrative figure that depicts and compares the classical projection method and our moving line method.
本文由计算部分和理论部分两部分组成。前者针对的是管状表面的计算机辅助几何设计。后者侧重于一组二次曲线的代数几何。在应用层面,我们提供了一种简单易行的计算算法,通过移动线合理地参数化广义实管曲面。我们发现可以从给定的投影二次曲线的隐式方程直接计算出合子,即移动线。具体地说,我们描述了三维空间中的两个线性多项式向量,它们的项是用给定的二次曲线隐式方程的系数表示的。然后证明了这两个向量实际上是一个μ基,是给定二次曲线的合模的生成子,并给出了给定二次曲线的有理参数化。在理论层面上,我们首先简要回顾了一般非退化二次曲线的有理参数化的经典投影方法。这与syzygy方法(即移动线条)相比较。最后,我们用一个插图来描述和比较经典投影法和我们的移动线法。
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引用次数: 0
Differential uniformity properties of some classes of permutation polynomials 几类置换多项式的微分均匀性
Pub Date : 2025-03-01 DOI: 10.1016/j.jaca.2025.100035
Kirpa Garg , Sartaj Ul Hasan , Pantelimon Stănică
The notion of c-differential uniformity has received a lot of attention since its proposal [5], and recently a characterization of perfect c-nonlinear functions in terms of difference sets in some quasigroups was obtained in [1]. Moreover, in a very recent manuscript by Pal and Stănică [19], an intriguing connection was discovered showing that in fact, the boomerang uniformity for an odd APN function (odd characteristic) equals its c-differential uniformity when c=1, if the function is a permutation, otherwise it is the maximum of the (1)-DDT entries disregarding the first row/column. The construction of functions, especially permutations, with low c-differential uniformity is an interesting and difficult mathematical problem in this area, and recent work has focused heavily in this direction. We provide a few classes of permutation polynomials with low c-differential uniformity. The used technique involves handling various Weil sums, as well as analyzing some equations in finite fields, and we believe these can be of independent interest, from a mathematical perspective.
自提出[5]以来,c-微分均匀性的概念受到了广泛的关注,最近在[1]中得到了一些准群中完备c-非线性函数在差分集上的刻画。此外,在Pal和striturnicei[19]最近的一篇手稿中,发现了一个有趣的联系,表明事实上,当c= - 1时,奇数APN函数(奇数特征)的回旋均匀性等于它的c-微分均匀性,如果函数是一个排列,否则它是(- 1)-DDT项的最大值,不管第一行/列。低c微分均匀性函数的构造,特别是排列的构造,是该领域中一个有趣而困难的数学问题,最近的工作主要集中在这个方向上。我们提供了几类低c微分均匀性的置换多项式。所使用的技术包括处理各种Weil和,以及分析有限域中的一些方程,我们相信从数学的角度来看,这些可能是独立的兴趣。
{"title":"Differential uniformity properties of some classes of permutation polynomials","authors":"Kirpa Garg ,&nbsp;Sartaj Ul Hasan ,&nbsp;Pantelimon Stănică","doi":"10.1016/j.jaca.2025.100035","DOIUrl":"10.1016/j.jaca.2025.100035","url":null,"abstract":"<div><div>The notion of <em>c</em>-differential uniformity has received a lot of attention since its proposal <span><span>[5]</span></span>, and recently a characterization of perfect <em>c</em>-nonlinear functions in terms of difference sets in some quasigroups was obtained in <span><span>[1]</span></span>. Moreover, in a very recent manuscript by Pal and Stănică <span><span>[19]</span></span>, an intriguing connection was discovered showing that in fact, the boomerang uniformity for an odd APN function (odd characteristic) equals its <em>c</em>-differential uniformity when <span><math><mi>c</mi><mo>=</mo><mo>−</mo><mn>1</mn></math></span>, if the function is a permutation, otherwise it is the maximum of the <span><math><mo>(</mo><mo>−</mo><mn>1</mn><mo>)</mo></math></span>-DDT entries disregarding the first row/column. The construction of functions, especially permutations, with low <em>c</em>-differential uniformity is an interesting and difficult mathematical problem in this area, and recent work has focused heavily in this direction. We provide a few classes of permutation polynomials with low <em>c</em>-differential uniformity. The used technique involves handling various Weil sums, as well as analyzing some equations in finite fields, and we believe these can be of independent interest, from a mathematical perspective.</div></div>","PeriodicalId":100767,"journal":{"name":"Journal of Computational Algebra","volume":"13 ","pages":"Article 100035"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Journal of Computational Algebra
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