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R. Thompson’s group and the amenability problem r。汤普森的团队和顺从问题
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-04-01 DOI: 10.1070/RM10040
V. Guba
This paper focuses on Richard Thompson’s group , which was discovered in the 1960s. Many papers have been devoted to this group. We are interested primarily in the famous problem of amenability of this group, which was posed by Geoghegan in 1979. Numerous attempts have been made to solve this problem in one way or the other, but it remains open. In this survey we describe the most important known properties of this group related to the word problem and representations of elements of the group by piecewise linear functions as well as by diagrams and other geometric objects. We describe the classical results of Brin and Squier concerning free subgroups and laws. We include a description of more modern important results relating to the properties of the Cayley graphs (the Belk–Brown construction) as well as Bartholdi’s theorem about the properties of equations in group rings. We consider separately the criteria for (non-)amenability of groups that are useful in the work on the main problem. At the end we describe a number of our own results about the structure of the Cayley graphs and a new algorithm for solving the word problem. Bibliography: 69 titles.
本文的研究重点是20世纪60年代发现的理查德·汤普森群体。许多论文都致力于这一群体。我们主要感兴趣的是这个群的易受性这个著名的问题,是盖根在1979年提出的。为了以这样或那样的方式解决这个问题,已经作了许多尝试,但它仍然是开放的。在这个调查中,我们描述了这个群的最重要的已知性质,这些性质与字问题有关,并通过分段线性函数以及图和其他几何对象表示这个群的元素。我们描述了Brin和Squier关于自由子群和定律的经典结果。我们包括了与Cayley图的性质(Belk-Brown构造)有关的更现代的重要结果的描述,以及关于群环中方程性质的Bartholdi定理。我们分别考虑了在主要问题的研究中有用的组的(非)适应性标准。最后,我们描述了一些我们自己的关于Cayley图的结构的结果和一个解决字问题的新算法。参考书目:69篇。
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引用次数: 1
Inequities in Telehealth Use Associated with Payer Type During the COVID-19 Pandemic. 在 COVID-19 大流行期间,与支付方类型相关的远程医疗使用不平等现象。
IF 4.7 4区 数学 Q1 MATHEMATICS Pub Date : 2022-03-31 DOI: 10.1089/tmj.2021.0618
Kanna N Lewis, Anthony Goudie, Jonathan C Wilson, Edward Tawiah, Jialiang Li, Joseph W Thompson

Introduction: The COVID-19 pandemic has prompted a shift in health care delivery and compelled a heavier reliance on telehealth. The objective of this study was to determine if differences in coverage policies by payer type resulted in differential telehealth use during the first 3 months of the COVID-19 pandemic. In this population-based cohort study of low-income Arkansans, Medicaid beneficiaries enrolled in the traditional Primary Care Case Management (PCCM) program were compared with Medicaid beneficiaries covered through premium assistance in private Qualified Health Plans (QHPs). Methods: A retrospective review was conducted of insurance claims records from June 1, 2019, to June 30, 2020, for synchronous telehealth and mobile health (m-health) visits, as well as other forms of telehealth. To establish the baseline equivalence of enrollees in the two groups, propensity score matching design was used on demographic and geographic characteristics, Charlson Comorbidity Index, broadband availability, and prior service utilization. Results: Compared with enrollees in the PCCM program, Medicaid expansion enrollees in QHPs had higher odds of having had at least one telehealth visit (adjusted odds ratio [aOR] = 1.35, 95% confidence interval [CI]: 1.29-1.42) during the early phase of the COVID-19 pandemic. Categorizing utilizations by domain, QHP enrollees were more likely to use synchronous telehealth (aOR = 1.31; 95% CI: 1.25-1.37) and m-health (aOR = 5.91; 95% CI: 4.25-8.21). A higher proportion of QHP enrollees also had at least one mental or behavioral health telehealth session (aOR = 1.13; 95% CI: 1.07-1.19). Conclusions: Our study demonstrated that within low-income populations, payer type was associated with inequitable access to telehealth during the early phase of the COVID-19 pandemic.

导言:COVID-19 大流行引发了医疗服务的转变,迫使人们更加依赖远程医疗。本研究的目的是确定在 COVID-19 大流行的前 3 个月中,不同支付方类型的承保政策是否会导致远程医疗使用的差异。在这项对阿肯色州低收入人群进行的基于人群的队列研究中,将参加传统的初级医疗个案管理 (PCCM) 计划的医疗补助受益人与通过私人合格健康计划 (QHP) 的保费补助获得保险的医疗补助受益人进行了比较。方法:对 2019 年 6 月 1 日至 2020 年 6 月 30 日期间的保险理赔记录进行了回顾性审查,以了解同步远程医疗和移动医疗 (m-health) 访问以及其他形式的远程医疗的情况。为确定两组参保者的基线等同性,对人口和地理特征、查尔森综合症指数、宽带可用性和之前的服务使用情况采用了倾向得分匹配设计。结果显示与 PCCM 计划的参保者相比,在 COVID-19 大流行的早期阶段,参加 QHPs 的医疗补助扩展计划的参保者接受过至少一次远程医疗访问的几率更高(调整后的几率比 [aOR] = 1.35,95% 置信区间 [CI]:1.29-1.42)。按领域对使用情况进行分类,QHP 参保者更有可能使用同步远程医疗(aOR = 1.31;95% CI:1.25-1.37)和移动医疗(aOR = 5.91;95% CI:4.25-8.21)。更高比例的 QHP 参保者还至少进行过一次心理或行为健康远程保健会话(aOR = 1.13;95% CI:1.07-1.19)。结论:我们的研究表明,在 COVID-19 大流行的早期阶段,在低收入人群中,支付方类型与远程医疗的不公平使用有关。
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引用次数: 0
Effect of excise tax on sugar-sweetened beverages in Catalonia, Spain, three and a half years after its introduction. 西班牙加泰罗尼亚地区对含糖饮料征收消费税三年半后的效果。
IF 5.6 4区 数学 Q1 MATHEMATICS Pub Date : 2022-03-12 DOI: 10.1186/s12966-022-01262-8
Miguel Ángel Royo-Bordonada, Carlos Fernández-Escobar, Carlos José Gil-Bellosta, Elena Ordaz

Background: The World Health Organisation urges countries to levy specific excise taxes on SSBs. Currently, more than 50 countries have introduced some type of tax on SSBs. In March 2017, the Autonomous Region of Catalonia approved the introduction of a tiered excise tax on SSBs for public health reasons. To evaluate the effect of the Catalonian excise tax on the price and purchase of sugar-sweetened beverages (SSBs) and their possible substitutes, i.e., non-sugar-sweetened beverages (NSSBs) and bottled water, three and half years after its introduction, and 1 year after the outbreak of the COVID-19 pandemic.

Methods: We analysed purchase data on soft drinks, fruit drinks and water, sourced from the Ministry of Agriculture food-consumption panel, in a random sample of 12,500 households across Spain. We applied the synthetic control method to infer the causal impact of the intervention, based on a Bayesian structural time-series model which predicts the counterfactual response that would have occurred in Catalonia, had no intervention taken place.

Results: As compared to the predicted (counterfactual) response, per capita purchases of SSBs fell by 0.17 l three and a half years after implementing the SSB tax in Catalonia, a 16.7% decline (95% CI: - 23.18, - 8.74). The mean SSB price rose by 0.11 €/L, an 11% increase (95% CI: 9.0, 14.1). Although there were no changes in mean NSSB prices, NSSB consumption rose by 0.19 l per capita, a 21.7% increase (95% CI: 18.25, 25.54). There were no variations in the price or consumption of bottled water. The effects were progressively greater over time, with SSB purchases decreasing by 10.4% at 1 year, 12.3% at 2 years, 15.3% at 3 years, and 16.7% at three and a half years of the tax's introduction.

Conclusions: The Catalonian SSB excise tax had a sustained and progressive impact over time, with a fall in consumption of as much as 16.7% three and half years after its introduction. The observed NSSB substitution effect should be borne in mind when considering the application of this type of tax to the rest of Spain.

背景:世界卫生组织敦促各国对固态饮料征收专门的消费税。目前,已有 50 多个国家对固态饮料征收了某种类型的税。2017 年 3 月,加泰罗尼亚自治区出于公共健康考虑,批准对固态饮料征收分级消费税。目的是评估加泰罗尼亚消费税对含糖饮料(SSB)及其可能的替代品(即非含糖饮料(NSSB)和瓶装水)的价格和购买量的影响:我们分析了从农业部食品消费面板中获得的软饮料、水果饮料和水的购买数据,这些数据来自西班牙全国 12,500 个家庭的随机抽样。我们采用合成控制法来推断干预措施的因果影响,该方法基于贝叶斯结构时间序列模型,可预测加泰罗尼亚地区在未采取干预措施的情况下会出现的反事实反应:与预测的(反事实)反应相比,加泰罗尼亚在征收固态饮料税三年半后,人均固态饮料购买量下降了 0.17 升,降幅为 16.7%(95% CI:- 23.18,- 8.74)。SSB 的平均价格上升了 0.11 欧元/升,增幅为 11%(95% CI:9.0,14.1)。虽然 NSSB 的平均价格没有变化,但人均 NSSB 消费量增加了 0.19 升,增幅为 21.7%(95% CI:18.25,25.54)。瓶装水的价格和消费量没有变化。随着时间的推移,效果逐渐增强,在征税 1 年后,固体饮料的购买量减少了 10.4%,2 年后减少了 12.3%,3 年后减少了 15.3%,3 年半后减少了 16.7%:加泰罗尼亚地区的苏打水消费税随着时间的推移产生了持续和渐进的影响,在征税三年半后,消费量下降了 16.7%。在考虑对西班牙其他地区征收此类税时,应考虑到观察到的 NSSB 替代效应。
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引用次数: 0
Elements of hyperbolic theory on an infinite-dimensional torus 无限维环面上双曲理论的基本原理
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-01-01 DOI: 10.1070/rm10058
S. Glyzin, A. Kolesov
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引用次数: 1
On a canonical basis of a pair of compatible Poisson brackets on a symplectic Lie algebra 辛李代数上一对相容泊松括号的正则基础
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-01-01 DOI: 10.1070/RM10035
A. A. Garazha
Every reductive complex Lie algebra g is equipped with the canonical Poisson structure {φ,ψ}(x) = (x, [dxφ, dxψ]), where φ and ψ are smooth functions on g, while dxφ and dxψ are treated as elements of g, which is identified with g∗ using the invariant inner product. Moreover, for every a ∈ g, a Poisson structure ‘with frozen argument’ is defined: {φ,ψ}a(x) = (a, [dxφ, dxψ]). An approach described in [1] makes it possible to work with Poisson structures using the language of linear algebra. The Poisson brackets { · , · }a and { · , · } are regarded as skew-symmetric bilinear forms fa and fx over the field K = C(g) on the space g⊗K of rational vector fields on g, where the element a is fixed and x is a generic element. Namely, if φ and ψ are polynomials, then dφ and dψ can be regarded as elements of g⊗K, and then {φ,ψ}(x) = fx(dφ, dψ) and {φ,ψ}a(x) = fa(dφ, dψ). The above approach can be used to solve an important problem in Hamiltonian mechanics, namely, the search for complete families of functions in bi-involution, that is, maximal families of functions commuting with respect to both Poisson brackets. The polynomials φ1, . . . , φs define a complete family of functions in bi-involution with respect to { · , · }a and { · , · } if and only if their differentials dφ1, . . . , dφs form a basis of a bi-Lagrangian subspace (that is, a maximal subspace which is isotropic with respect to both bilinear forms). Thus, to obtain a complete family of functions in bi-involution, it suffices to find a basis for a bi-Lagrangian subspace and ‘integrate with respect to x’. If a basis is found (we call it canonical) in which the matrices of both forms fa and fx are reduced simultaneously to the canonical Jordan–Kronecker form (with blocks of two types, Jordan and Kronecker, see [1]), then a basis of the bi-Lagrangian subspace is formed by the second halves of the bases in each block. The second (‘larger’) halves of the bases in Kronecker blocks span a subspace L, which is the intersection of all bi-Lagrangian subspaces for the forms fa and fx. In [4] a basis of the subspace L and the corresponding functions in bi-involution were constructed for the Lie algebras gln and sp2n. In [3] the Kronecker part of a canonical basis and the corresponding part of the complete system of functions in bi-involution were constructed for the Lie algebra gln. Now we introduce our notation and formulate the result. Let {λ1, . . . , λs} be distinct eigenvalues of a matrix A ∈ gln. Assume that Jordan cells of order nk,1 ⩾ · · · ⩾ nk,ik correspond to an eigenvalue λk. We write
每个约化复李代数g都具有正则泊松结构{φ,ψ}(x) = (x, [dxφ, dxψ]),其中φ和ψ是g上的光滑函数,而dxφ和dxψ被看作g的元素,用不变内积来标识g∗。此外,对于每一个a∈g,定义了一个'具有固定参数'的泊松结构:{φ,ψ}a(x) = (a, [dxφ, dxψ])。[1]中描述的一种方法使得使用线性代数语言处理泊松结构成为可能。将泊松括号{·,·}a和{·,·}看作g上有理向量场的空间g⊗K上K = C(g)上的偏对称双线性形式fa和fx,其中元素a是固定的,x是一般元素。即,若φ和ψ是多项式,则dφ和dψ可视为g⊗K的元素,则{φ,ψ}(x) = fx(dφ, dψ)和{φ,ψ}a(x) = fa(dφ, dψ)。上述方法可用于解决哈密顿力学中的一个重要问题,即寻找双对合函数的完全族,即在两个泊松括号中交换的极大族函数。多项式φ1,…, φs定义了关于{·,·}和{·,·}双对合的完备函数族,当且仅当它们的微分dφ1,…。, dφs构成双拉格朗日子空间(即对两种双线性形式均各向同性的极大子空间)的一组基。因此,要得到双对合的完整函数族,只要找到双拉格朗日子空间的一组基并对x积分就足够了。如果找到一个基(我们称之为正则基),其中两种形式fa和fx的矩阵同时约简为正则Jordan - Kronecker形式(具有Jordan和Kronecker两种类型的块,见[1]),则由每个块中的基的后半部分构成双拉格朗日子空间的一组基。Kronecker块中基的第二部分(“较大的”)张成一个子空间L,它是形式fa和fx的所有双拉格朗日子空间的交集。在[4]中,构造了李代数gln和sp2n的子空间L的一组基及其对合函数。在[3]中,构造了李代数gln的正则基的Kronecker部分和双对合完全函数系统的相应部分。现在我们引入我们的符号并将结果公式化。设{λ1,…, λs}是矩阵a∈gln的不同特征值。假设nk,1或大于或等于nk,ik阶的Jordan细胞对应于一个特征值λk。我们写
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引用次数: 1
Left-invariant optimal control problems on Lie groups: classification and problems integrable by elementary functions 李群上的左不变最优控制问题:分类和可被初等函数积分的问题
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-01-01 DOI: 10.1070/RM10019
Y. Sachkov
Left-invariant optimal control problems on Lie groups are an important class of problems with a large symmetry group. They are theoretically interesting because they can often be investigated in full and general laws can be studied by using these model problems. In particular, problems on nilpotent Lie groups provide a fundamental nilpotent approximation to general problems. Also, left-invariant problems often arise in applications such as classical and quantum mechanics, geometry, robotics, visual perception models, and image processing. The aim of this paper is to present a survey of the main concepts, methods, and results pertaining to left-invariant optimal control problems on Lie groups that can be integrated by elementary functions. The focus is on describing extremal trajectories and their optimality, the cut time and cut locus, and optimal synthesis. Questions concerning the classification of left-invariant sub-Riemannian problems on Lie groups of dimension three and four are also addressed. Bibliography: 91 titles.
李群上的左不变最优控制问题是一类具有大对称群的重要问题。它们在理论上很有趣,因为它们通常可以被完整地研究,并且可以通过使用这些模型问题来研究一般定律。特别地,幂零李群问题为一般问题提供了一个基本的幂零近似。此外,左不变问题经常出现在经典力学和量子力学、几何、机器人、视觉感知模型和图像处理等应用中。本文的目的是提出一个主要的概念,方法和结果有关的左不变最优控制问题的李群,可由初等函数积分。重点是描述极值轨迹及其最优性,切割时间和切割轨迹,以及最优合成。讨论了三维和四维李群上的左不变子黎曼问题的分类问题。参考书目:91篇。
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引用次数: 7
On Voronoi’s conjecture for four- and five-dimensional parallelohedra 关于四维和五维平行四面体的Voronoi猜想
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-01-01 DOI: 10.1070/RM10020
A. Garber, A. Magazinov
1. Parallelohedra and Voronoi’s conjecture. A convex d-dimensional polytope is called a parallelohedron or a d-parallelohedron if there is a tiling of the space R into parallel copies of P . In particular, all parallelograms and all hexagons with a centre of symmetry are 2-parallelohedra. All five types of 3-parallelohedra were classified by Fedorov at the end of the 19th century. The theory of parallelohedra has its origins in the works by Fedorov, Minkowski, Voronoi, and Delone. Parallelohedra are closely connected with mathematical crystallography, the classification of crystallographic groups, algorithmic and geometric questions relating to integer lattices, and, in particular, with Hilbert’s 18th problem. Voronoi’s conjecture [1] is one of the central conjectures in the theory of parallelohedra. It states that for each d-parallelohedron P , there is a d-dimensional lattice Λ such that P is affinely equivalent to the Dirichlet–Voronoi cell of Λ. If Voronoi’s conjecture holds for P , then we call it a V-parallelohedron. Voronoi’s conjecture has been proved fully for d ⩽ 5. The cases d = 1, 2, 3 are common wisdom. The proof for d = 4 was given by Delone [2] in 1929. For d = 5, the proof was obtained by the authors of the present paper in 2019; see [3]. A review of key results in the theory of parallelohedra can be found in [4], Chap. 3, and in [5]. In this note we present a new proof of Voronoi’s conjecture in R, which uses ideas from [3] adapted for d = 4. For instance, our proof relies on a combinatorial approach, in contrast to Delone’s geometric methods. Both approaches use a number of general properties of parallelohedra, and, in particular, a classification of the types of coincidence of parallelohedra at faces of codimension three and the existence of a layered structure of tilings into parallelohedra under certain constraints. However, we rely on combinatorial methods developed long after Delone’s publication. In conclusion, we present a sketch of the proof of Voronoi’s conjecture for d = 5 from [3].
1. 平行四面体和Voronoi猜想。如果空间R被平铺成P的平行副本,那么一个凸的d维多面体就被称为平行四面体或d平行四面体。特别地,所有平行四边形和所有有对称中心的六边形都是2平行四面体。费多罗夫在19世纪末对所有五种三平行四面体进行了分类。平行四面体理论起源于费多罗夫、闵可夫斯基、沃罗诺伊和德龙的著作。平行四面体与数学晶体学、晶体群的分类、与整数晶格有关的算法和几何问题,特别是与希尔伯特第18个问题密切相关。Voronoi猜想[1]是平行四面体理论的中心猜想之一。它指出,对于每个d平行四面体P,存在一个d维晶格Λ,使得P与Λ的Dirichlet-Voronoi细胞仿射等效。如果Voronoi的猜想对P成立,那么我们称它为v平行四面体。对于d≤5,Voronoi猜想得到了充分证明。情况d = 1,2,3是常识。d = 4的证明是由Delone[2]在1929年给出的。对于d = 5,证明由本文作者在2019年获得;参见[3]。平行四面体理论的主要结果的回顾可以在b[4],第3章和b[5]中找到。在这篇文章中,我们给出了Voronoi猜想在R中的一个新的证明,它使用了[3]的思想,适用于d = 4。例如,我们的证明依赖于组合方法,而不是德龙的几何方法。这两种方法都使用了平行四面体的一些一般性质,特别是对平行四面体在余维三面的重合类型的分类,以及在某些约束下平行四面体的分层结构的存在。然而,我们依赖的是在德龙发表论文很久之后发展起来的组合方法。最后,我们给出了从[3]证明d = 5的Voronoi猜想的一个草图。
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引用次数: 0
Spectrum of a convolution operator with potential 具有势的卷积算子的谱
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-01-01 DOI: 10.1070/rm10038
D. Borisov, E. Zhizhina, Andrey L. Piatnitski
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引用次数: 0
Boris Abramovich Trakhtenbrot 鲍里斯·阿布拉莫维奇·特拉赫滕布罗特
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-01-01 DOI: 10.1070/RM10048
S. Artemov, J. Bārzdiņš, L. A. Bokut', Yuri Gurevich, A. M. Dekhtyar', L. Levin, I. Lomazova, Y. Matiyasevich, V. A. Nepomnyashchii, S. P. Novikov, A. Rabinovich, V. Sazonov, A. O. Slisenko, V. Sokolov, M. Trakhtenbrot, N. V. Shilov
Boris Abramovich Trakhtenbrot (20.02.1921– 19.09.2016), the centenary of whose birth was celebrated on 20 February 2021, was one of the founders of theoretical computer science, who was widely recognised both in the Soviet Union and all over the world. His scientific biography is also interesting in both its humanistic and historical aspects. He was born on 20 February 1921 in Bessarabia, in the village of Brichevo (which during various periods of time belonged to Russia, Romania, USSR, and Moldova). In 1940 he started studying mathematics at the Kishinev Pedagogical Institute (now Ion Creangă State Pedagogical University). At the beginning of World War II he was evacuated to the Urals with the Institute. By that time Kishinev was already under bombardment. Until 1943 he was completely out of touch with his family, which was separated and deported from Bessarabia to the Urals and Siberia during the large-scale eviction in June of 1941 (paradoxically, this exile saved his family from the Holocaust). Trakhtenbrot was disqualified from active military service because of his weak eyesight. During that period he combined intermittent studies with working at a footwear factory and in a gas trust company. In 1944 he returned from evacuation. For a year he worked as a teacher of mathematics in the town of Beltsy (now Moldovan Bălţi). He completed his mathematical studies at the University of Chernovtsy (now Ukrainian Chernivtsi) in 1945–1947. Parallel to his studies, he took an active part in the restoration of the well-stocked mathematical library of Chernovtsy State University, and this activity played an important role in his education and familiarization with science. A number of teachers at Chernovtsy State University were disciples of Moscow mathematical schools. Among those who had great influence on Trakhtenbrot was A.A. Bobrov, a former student of A. N. Kolmogorov. It was at Bobrov’s seminar on Hausdorff’s monograph that Trakhtenbrot became fascinated by descriptive set theory. On the
鲍里斯·阿布拉莫维奇·特拉赫滕布罗特(Boris Abramovich Trakhtenbrot, 1921年2月20日- 2016年9月19日)是理论计算机科学的创始人之一,在苏联和全世界都得到了广泛的认可。他的科学传记在人文和历史方面也很有趣。他于1921年2月20日出生于比萨拉比亚的布里切沃村(该村在不同时期属于俄罗斯、罗马尼亚、苏联和摩尔多瓦)。1940年,他开始在基什涅夫教育学院(现为伊昂·克里昂热国立教育大学)学习数学。第二次世界大战开始时,他和研究所一起被疏散到乌拉尔。那时基什涅夫已经处于轰炸之中。直到1943年,他与家人完全失去了联系,在1941年6月的大规模驱逐中,他的家人被分开并从比萨拉比亚驱逐到乌拉尔和西伯利亚(矛盾的是,这次流放使他的家人免于大屠杀)。由于视力不佳,特拉赫滕布罗特被取消了现役资格。在此期间,他一边断断续续地学习,一边在一家鞋厂和一家天然气信托公司工作。1944年,他从撤离中回来。他在Beltsy镇(现在的摩尔多瓦Bălţi)当了一年的数学老师。1945年至1947年,他在切尔诺夫茨大学(现乌克兰切尔诺夫茨)完成了数学研究。在学习的同时,他还积极参与了切尔诺夫茨国立大学藏书丰富的数学图书馆的修复工作,这项活动对他的教育和熟悉科学起了重要作用。切尔诺夫茨国立大学的许多教师都是莫斯科数学学校的学生。在对特拉赫滕布罗特有很大影响的人当中,有a·a·博布罗夫,他以前是a·n·科尔莫哥罗夫的学生。正是在Bobrov关于Hausdorff专著的研讨会上,Trakhtenbrot开始对描述性集合论着迷。在
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引用次数: 0
Evgenii Vital'evich Shchepin (on his seventieth birthday) 叶夫根尼·维塔耶维奇·谢普平(庆祝他七十大寿)
IF 0.9 4区 数学 Q1 MATHEMATICS Pub Date : 2022-01-01 DOI: 10.1070/rm10043
V. Buslaev, V. Buchstaber, A. Dranishnikov, Vitalii Mendelevich Kliatskin, S. A. Melikhov, L. Montejano, S. Novikov, P. Semenov
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引用次数: 0
期刊
Russian Mathematical Surveys
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