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POLYNOMIAL REPRESENTATIONS OF THE AFFINE NAPPI-WITTEN LIE ALGEBRA H_4 被引量:1
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作者 陈雪 黄智力 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2105-2118,共14页
In this paper, the representation theory for the arlene Lie algebra H4 associated to the Nappi-Witten Lie algebra H4 is studied. Polynomial representations of the affine Nappi-Witten Lie algebra H4 are given.
关键词 affine Nappi-Witten Lie algebra POLYNOMIAL REPRESENTATION
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Pairing Problem of Generators in Non twisted Affine Lie Algebras 被引量:1
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作者 徐海霞 卢才辉 《Northeastern Mathematical Journal》 CSCD 2001年第1期111-119,共9页
In this paper, we discuss the pairing problem of generators in four affine Lie algebra. That is, for any given imaginary root vector x∈g(A) , there exists y such that x and y generate a subalgebra cont... In this paper, we discuss the pairing problem of generators in four affine Lie algebra. That is, for any given imaginary root vector x∈g(A) , there exists y such that x and y generate a subalgebra containing g′(A). 展开更多
关键词 affine Lie algebra imaginary root vector pairing generator
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水环境中BPAF光化学转化及其影响因素
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作者 黄睿媛 曾祥英 +4 位作者 吴毅钉 吴杨 王典 梁医 于志强 《地球化学》 CAS CSCD 北大核心 2024年第6期793-800,共8页
随着双酚A的限用和禁用,双酚AF(BPAF)作为替代品被广泛使用,BPAF在环境中的检出频率和浓度水平也逐渐增加。本研究通过光化学模拟实验探索水体环境中BPAF光化学行为,考察初始浓度、溶液pH值以及水体中共存溶解有机质(DOM)对光降解转化... 随着双酚A的限用和禁用,双酚AF(BPAF)作为替代品被广泛使用,BPAF在环境中的检出频率和浓度水平也逐渐增加。本研究通过光化学模拟实验探索水体环境中BPAF光化学行为,考察初始浓度、溶液pH值以及水体中共存溶解有机质(DOM)对光降解转化的影响。结果显示,BPAF可吸收一定波长紫外光直接发生光降解转化,生成OH-BPAF和BPAF-(COOH)_(2),也可能聚合生成更高分子量的二聚体。同时,碱性条件下离子态的BPAF具有更强的紫外吸收能力,降解效率明显提高;水体中共存的DOM通过光子竞争与光屏蔽效应抑制BPAF降解转化。 展开更多
关键词 双酚af 溶解有机质 光降解 光转化
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Cluster algebra structure on the finite dimensional representations of affine quantum group U_q(_3)
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作者 杨彦敏 马海涛 +1 位作者 林冰生 郑驻军 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期119-124,共6页
In this paper, we prove one case of conjecture given by Hemandez and Leclerc. We give a cluster algebra structuure on the Grothendieck ring of a full subcategory of the finite dimensional representations of affine qua... In this paper, we prove one case of conjecture given by Hemandez and Leclerc. We give a cluster algebra structuure on the Grothendieck ring of a full subcategory of the finite dimensional representations of affine quantum group Uq(A3). As a conclusion, for every exchange relation of cluster algebra, there exists an exact sequence of the full subcategory corresponding to it. 展开更多
关键词 affine quantum group cluster algebra monoidal categorification
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Vertex Algebra Sheaf Structure on Torus
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作者 SUN Yuan-yuan 《Chinese Quarterly Journal of Mathematics》 2016年第1期44-50,共7页
In this paper, we first give a 1-1 corresponds between torus C/Λ and cubic curve C in P_C^2. As complex manifold, they are isomorphic, therefore we can treat C/Λ as a variety and construction a vertex algebra sheaf ... In this paper, we first give a 1-1 corresponds between torus C/Λ and cubic curve C in P_C^2. As complex manifold, they are isomorphic, therefore we can treat C/Λ as a variety and construction a vertex algebra sheaf on it. 展开更多
关键词 TORUS vertex algebra SHEaf
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基于CHARGE-AF模型评估减重术对心房颤动发生风险的影响
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作者 彭荣刚 孟伟伦 +4 位作者 高其忠 曲伸 张毅 徐亚伟 王晓彦 《中国循证心血管医学杂志》 2024年第2期198-201,共4页
目的通过CHARGE-AF模型评估外科减重术对肥胖症患者心房颤动(房颤)发生风险的影响。方法纳入2016年8月至2020年5月期间入院拟行袖状胃切除术(LSG术)的肥胖症患者,收集并记录受试者行LSG术前及术后的相关病史、体格检查和心电图结果,根据... 目的通过CHARGE-AF模型评估外科减重术对肥胖症患者心房颤动(房颤)发生风险的影响。方法纳入2016年8月至2020年5月期间入院拟行袖状胃切除术(LSG术)的肥胖症患者,收集并记录受试者行LSG术前及术后的相关病史、体格检查和心电图结果,根据CHARGE-AF模型和CHARGE-AF增强模型公式计算房颤发生风险。结果研究共纳入67例受试者,平均随访时间为11.11±5.51个月。LSG术后受试者的体重、收缩压、舒张压、降压药物服用率、糖尿病患病率、心肌肥厚发生率、PR间期<120 ms发生率均显著性降低。而抽烟率、心力衰竭(心衰)患病率、心肌梗死(心梗)患病率、PR间期>199 ms未发生显著性变化。根据CHARGE-AF模型公式计算,受试者房颤发生风险呈降低趋势,由(0.11±0.10)%降至(0.08±0.08)%,(P=0.07)。根据CHARGE-AF增强模型计算,受试者房颤发生风险显著降低,由(0.12±0.12)%降至(0.08±0.08)%,(P<0.05)。将体重变量单因素纳入模型计算出受试者房颤发生风险显著降低(P<0.001)。结论肥胖症患者在减重术后房颤发生的可能危险因素(如体重、血压、心室肥厚等)均得到显著改善,房颤的发生风险显著降低。 展开更多
关键词 CHARGE-af模型 肥胖症 减重术 风险评估
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P-Twisted Affine Lie Algebras and Their Associated Vertex Algebras
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作者 DING Lu ZHENG Zhu-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期7-12,共6页
For any finite-dimensional semisimple Lie algebra g, a Z+-graded vertex algebra is construsted on the vacuum representation Vk(g[θ]of g[θ]),which is a one-dimentionM central extension of 8-invariant subspace on t... For any finite-dimensional semisimple Lie algebra g, a Z+-graded vertex algebra is construsted on the vacuum representation Vk(g[θ]of g[θ]),which is a one-dimentionM central extension of 8-invariant subspace on the loop algebra Lg=g C((t^1/p)). 展开更多
关键词 p-twisted affine Lie algebra vertex algebra
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基于改进AF法的中国多维相对贫困测度研究
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作者 张英杰 苏宇楠 蔺子航 《中央民族大学学报(自然科学版)》 2024年第3期73-80,共8页
本文采用变异系数修正AHP的改进AF法,基于CFPS数据库运用“双阈值法”,对我国相对贫困问题进行识别和分解,并利用分位数回归讨论高低分位水平下各指标对相对贫困的影响程度。研究表明:第一,我国多维相对贫困的发生率整体呈下降趋势,多... 本文采用变异系数修正AHP的改进AF法,基于CFPS数据库运用“双阈值法”,对我国相对贫困问题进行识别和分解,并利用分位数回归讨论高低分位水平下各指标对相对贫困的影响程度。研究表明:第一,我国多维相对贫困的发生率整体呈下降趋势,多维相对贫困主要集中在农村地区;第二,多维相对贫困群体在生活水平、人均家庭收入和儿童失学率遭受的相对剥夺最突出,前两者对相对贫困呈负向影响,儿童失学率对相对贫困呈正向影响;第三,各指标对不同相对贫困水平下的人群影响是不同的。债务对于贫困指标数最多的群体影响最大,文娱支出更能反映小康小富群体的相对贫困情况,人均纯收入、人均住房价值和金融产品更能体现生活条件较好家庭的相对贫困状态。 展开更多
关键词 多维相对贫困指数 修正AHP 改进af
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Realization of Vertex Operators of 7-Twisted Affine Lie Algebra ■[θ]
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作者 郑驻军 董文峰 楚彦军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期423-429,共7页
In this paper, we construct a new algebra structure 7-twisted atone Lie algebra sl(3,C)[θ] and study its vertex operator representations.
关键词 twisted affine Lie algebra vertex operator representations vertex operator
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Algebraic Points of Any Degree l with (l ≥ 9) over Q on the Affine Equation Curve C3 (11): y11 = x3(x-1)3
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作者 Boubacar Sidy Balde Mohamadou Mor Diogou Diallo Oumar Sall 《Advances in Pure Mathematics》 2022年第9期519-525,共7页
In this work, we use the finiteness of the Mordell-weil group and the Riemann Roch spaces to give a geometric parametrization of the set of algebraic points of any given degree over the field of rational numbers Q on ... In this work, we use the finiteness of the Mordell-weil group and the Riemann Roch spaces to give a geometric parametrization of the set of algebraic points of any given degree over the field of rational numbers Q on curve C<sub>3 </sub>(11): y<sup>11</sup> = x<sup>3</sup> (x-1)<sup>3</sup>. This result is a special case of quotients of Fermat curves C<sub>r,s </sub>(p) : y<sup>p</sup> = x<sup>r</sup>(x-1)<sup>s</sup>, 1 ≤ r, s, r + s ≤ p-1 for p = 11 and r = s = 3. The results obtained extend the work of Gross and Rohrlich who determined the set of algebraic points on C<sub>1</sub>(11)(K) of degree at most 2 on Q. 展开更多
关键词 Mordell-Weil Group JACOBIAN Galois Conjugates algebraic Extensions the Abel-Jacobi Theorem Linear Systems
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Integral Basis of Affine Vertex Algebra <i>V<sub>k</sub></i>(sl<sub>2</sub>) and Virasoro Vertex Algebra <i>V</i><sub><i>vir</i></sub>(2<i>k</i>,0)
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作者 Ashuai Wang 《Journal of Applied Mathematics and Physics》 2020年第4期652-659,共8页
In this paper, we consider an integral basis for affine vertex algebra Vk (sl2) when the level k is integral by a direct calculation, then use the similar way to analyze an integral basis for Virasoro vertex algebra V... In this paper, we consider an integral basis for affine vertex algebra Vk (sl2) when the level k is integral by a direct calculation, then use the similar way to analyze an integral basis for Virasoro vertex algebra Vvir (2k,0). Finally, we take the combination of affine algebras and Virasoro Lie algebras into consideration. By analogy with the construction of Lie algebras over Z using Chevalley bases, we utilize the Z-basis of Lav whose structure constants are integral to find an integral basis for the universal enveloping algebra of it. 展开更多
关键词 Vertex algebra Integral Basis VIRASORO algebra afFINE algebra
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Imaginary Whittaker Modules of the Twisted Affine Nappi-Witten Lie Algebra <img src="http://admin.scirp.org/Editer/attached/image/Edit_fc740d60-7009-4d6f-939a-ac2a113f1539.bmp"alt=""/>
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作者 Xue Chen 《Journal of Applied Mathematics and Physics》 2020年第3期548-554,共7页
The Nappi-Witten Lie algebra was first introduced by C. Nappi and E. Witten in the study of Wess-Zumino-Novikov-Witten (WZNW) models. They showed that the WZNW model (NW model) based on a central extension of the two-... The Nappi-Witten Lie algebra was first introduced by C. Nappi and E. Witten in the study of Wess-Zumino-Novikov-Witten (WZNW) models. They showed that the WZNW model (NW model) based on a central extension of the two-dimensional Euclidean group describes the homogeneous four-dimensional space-time corresponding to a gravitational plane wave. The associated Lie algebra is neither abelian nor semisimple. Recently K. Christodoulopoulou studied the irreducible Whittaker modules for finite- and infinite-dimensional Heisenberg algebras and for the Lie algebra obtained by adjoining a degree derivation to an infinite-dimensional Heisenberg algebra, and used these modules to construct a new class of modules for non-twisted affine algebras, which are called imaginary Whittaker modules. In this paper, imaginary Whittaker modules of the twisted affine Nappi-Witten Lie algebra are constructed based on Whittaker modules of Heisenberg algebras. It is proved that the imaginary Whittaker module with the center acting as a non-zero scalar is irreducible. 展开更多
关键词 TWISTED afFINE Nappi-Witten Lie algebraS Heisenberg algebraS Imagi-nary Whittaker MODULES
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扩孔参数对AF1410超高强度钢切屑微观形貌的影响
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作者 何世琦 宋万万 +2 位作者 郑英晓 王奔 张秀云 《工具技术》 北大核心 2024年第6期61-64,共4页
通过对AF1410钢扩孔加工试验探究主轴转速和进给速度对切屑微观形貌的影响,为改善切屑形貌提升AF1410超高强度钢的扩孔质量提供依据。对有典型形貌特征切屑的自由表面、后表面和上表面进行观测,结果表明,切屑自由表面均为锯齿状片层结... 通过对AF1410钢扩孔加工试验探究主轴转速和进给速度对切屑微观形貌的影响,为改善切屑形貌提升AF1410超高强度钢的扩孔质量提供依据。对有典型形貌特征切屑的自由表面、后表面和上表面进行观测,结果表明,切屑自由表面均为锯齿状片层结构且锯齿片层的宽度随主轴转速和进给速度的增加而增加。切屑后表面整体较光滑,随着主轴转速的增加,后表面光滑程度增加,利于提升已加工表面质量,且在主轴转速为800r/min时,顶部出现撕裂锯齿状毛边,同时进给速度对后表面影响较小。切屑上表面均呈周期锯齿状,切屑厚度随主轴转速增加而减小,锯齿高度随着主轴转速和进给速度的增加而增加。 展开更多
关键词 af1410超高强度钢 扩孔参数 切屑微观形貌 自由表面 后表面 上表面
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THE BSE PROPERTY FOR SOME VECTOR-VALUED BANACH FUNCTION ALGEBRAS
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作者 Fatemeh ABTAHI Ali REJALI Farshad SAYAF 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1945-1954,共10页
In this paper,X is a locally compact Hausdorff space and A is a Banach algebra.First,we study some basic features of C0(X,A)related to BSE concept,which are gotten from A.In particular,we prove that if C0(X,A)has the ... In this paper,X is a locally compact Hausdorff space and A is a Banach algebra.First,we study some basic features of C0(X,A)related to BSE concept,which are gotten from A.In particular,we prove that if C0(X,A)has the BSE property then A has so.We also establish the converse of this result,whenever X is discrete and A has the BSE-norm property.Furthermore,we prove the same result for the BSE property of type I.Finally,we prove that C0(X,A)has the BSE-norm property if and only if A has so. 展开更多
关键词 BSE algebras BSE-function BSE norm multiplier algebra SEMISIMPLE without order
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Groupoid Approach to Ergodic Dynamical System of Commutative von Neumann Algebra
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作者 Nicholas O. Okeke Murphy E. Egwe 《Advances in Pure Mathematics》 2024年第3期167-184,共18页
Given a compact and regular Hausdorff measure space (X, μ), with μ a Radon measure, it is known that the generalised space M(X) of all the positive Radon measures on X is isomorphic to the space of essentially bound... Given a compact and regular Hausdorff measure space (X, μ), with μ a Radon measure, it is known that the generalised space M(X) of all the positive Radon measures on X is isomorphic to the space of essentially bounded functions L<sup>∞</sup>(X, μ) on X. We confirm that the commutative von Neumann algebras M⊂B(H), with H=L<sup>2</sup>(X, μ), are unitary equivariant to the maximal ideals of the commutative algebra C(X). Subsequenly, we use the measure groupoid to formulate the algebraic and topological structures of the commutative algebra C(X) following its action on M(X) and define its representation and ergodic dynamical system on the commutative von Neumann algebras of M of B(H) . 展开更多
关键词 Measure Groupoid Groupoid Equivalence Ergodic Action Convolution algebra von Neumann algebra Generalized Space
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AF/KDF4滤棒成型机组远程监控与风险预警系统的设计应用
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作者 何超 郭阁 +5 位作者 喻涛 罗启睿 彭国事 敖茂 安靖 周易文 《物联网技术》 2024年第7期18-22,共5页
为提升滤棒生产的加工控制水平和产品质量稳定性,设计开发了AF/KDF4滤棒成型机组远程监控与风险预警系统。采用ADS及工业以太网协议,使用C#语言编程,实现了AF/KDF4滤棒成型机组运行参数的远程读取。通过对采集的数据进行处理、分析和可... 为提升滤棒生产的加工控制水平和产品质量稳定性,设计开发了AF/KDF4滤棒成型机组远程监控与风险预警系统。采用ADS及工业以太网协议,使用C#语言编程,实现了AF/KDF4滤棒成型机组运行参数的远程读取。通过对采集的数据进行处理、分析和可视化呈现,实现了滤棒成型机组实时运行状态的远程监控、关键工艺参数的预警及预警信息的推送等功能。应用结果表明:使用该系统后,实现了对滤棒成型机组的远程监控以及参数的读取,预警准确率为99.1%,滤棒质量综合管控水平得到了有效提升。 展开更多
关键词 af/KDF4滤棒成型机组 ADS协议 设备参数 远程监控 数据可视化 风险预警
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BANACH ALGEBRA STRUCTURE IN DERIVATIVE HARDY SPACES
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作者 ZHANG Zhao-de LIU Jun-ming 《数学杂志》 2024年第6期485-493,共9页
In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and... In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and describe the extended eigenvalue of the integral operator V.We generalize the results in[1,2,6,11,16]. 展开更多
关键词 Duhamel product banach algebra extended eigenvalue
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AF患者LAAO术前LAA开口参数与术中置入封堵器尺寸的相关性及术后PDL发生的影响因素分析
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作者 柴夏宁 王新文 +4 位作者 杨敏 赵继敏 王杰 丁金祥 高楠琳 《中国临床新医学》 2024年第4期432-436,共5页
目的分析心房颤动(AF)患者左心耳封堵(LAAO)术前左心耳(LAA)开口参数与术中置入封堵器尺寸的相关性及术后器械周围残余分流(PDL)发生的影响因素。方法回顾性分析2019年1月至2022年12月于山西医科大学第二医院成功实施LAAO术的83例非瓣膜... 目的分析心房颤动(AF)患者左心耳封堵(LAAO)术前左心耳(LAA)开口参数与术中置入封堵器尺寸的相关性及术后器械周围残余分流(PDL)发生的影响因素。方法回顾性分析2019年1月至2022年12月于山西医科大学第二医院成功实施LAAO术的83例非瓣膜性AF患者的临床资料。根据术后PDL发生情况将其分为PDL组(23例)和无PDL组(60例)。比较两组患者的临床资料和LAA开口参数。采用Pearson相关分析无PDL组LAA开口参数与术中置入封堵器尺寸的相关性。采用logistic回归分析术后PDL发生的影响因素。结果PDL组年龄显著小于无PDL组(P<0.05),两组性别、合并基础疾病情况比较差异无统计学意义(P>0.05)。PDL组LAA开口长径、短径、周长、面积大于无PDL组,差异有统计学意义(P<0.05)。Pearson相关分析结果显示,无PDL组LAA开口长径、短径、周长、面积与置入封堵器尺寸呈正相关(P<0.05)。多因素logistic回归分析结果显示,较大的年龄是术后PDL发生的独立保护因素,较大的LAA开口短径是术后PDL发生的独立危险因素(P<0.05)。结论LAA开口参数与封堵器尺寸呈正相关,其中LAA开口面积与封堵器尺寸的相关性最好,可为临床上封堵器的选择提供指导作用。较大的年龄是LAAO术后PDL发生的独立保护因素,较大的LAA开口短径是LAAO术后PDL发生的独立危险因素。 展开更多
关键词 左心耳CT成像 心房颤动 左心耳封堵术 器械周围残余分流 左心耳开口
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Split-Tetraquaternion Algebra and Applications
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作者 Grégoire Lutanda Panga 《Journal of Applied Mathematics and Physics》 2024年第7期2682-2690,共9页
In this paper, from the spacetime algebra associated with the Minkowski space ℝ3,1by means of a change of signature, we describe a quaternionic representation of the split-tetraquaternion algebra which incorporates th... In this paper, from the spacetime algebra associated with the Minkowski space ℝ3,1by means of a change of signature, we describe a quaternionic representation of the split-tetraquaternion algebra which incorporates the Pauli algebra, the split-biquaternion algebra and the split-quaternion algebra, we relate these algebras to Clifford algebras and we show the emergence of the stabilized Poincaré-Heisenberg algebra from the split-tetraquaternion algebra. We list without going into details some of their applications in Physics and in Born geometry. 展开更多
关键词 Tetraquaternion algebra Split-Tetraquaternion algebra Split Quaternion algebra Clifford algebra
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Discussion on the Homology Theory of Lie Algebras
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作者 Lilong Kang Yu Wang Caiyu Du 《Journal of Applied Mathematics and Physics》 2024年第7期2367-2376,共10页
Because homology on compact homogeneous nilpotent manifolds is closely related to homology on Lie algebras, studying homology on Lie algebras is helpful for further studying homology on compact homogeneous nilpotent m... Because homology on compact homogeneous nilpotent manifolds is closely related to homology on Lie algebras, studying homology on Lie algebras is helpful for further studying homology on compact homogeneous nilpotent manifolds. So we start with the differential sequence of Lie algebras. The Lie algebra g has the differential sequence E0,E1,⋯,Es⋯, which leads to the chain complex Es0→Δs0Ess→Δs1⋯→ΔsiEs(i+1)s→Δsi+1⋯of Esby discussing the chain complex E10→Δ10E11→Δ11⋯→Δ1r−1E1r→Δ1r⋯of E1and proves that Es+1i≅Hi(Es)=KerΔsi+1/ImΔsiand therefore Es+1≅H(Es)by the chain complex of Es(see Theorem 2). 展开更多
关键词 Lie algebra Differential Sequence Differential Fractional algebra COHOMOLOGY
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