摘要 / Abstract 中文摘要 本文从挂谷猜想出发,探讨建立、发展和完善动态欧氏几何这一亚科的现实意义与长远影响。欧氏几何(Euclid《几何原本》;Hilbert《几何基础》, 1899)建立点、线、面之间的关联关系、全等条件、平行公设与连续性,用以描述静态图形。Kakeya 问题(1907)及其 Besicovitch–Perron 构造(1928)则涉及维度动态升级——一维单位线段如何通过操作链变成含各方向单位线段的二维覆盖,且此覆盖测度可多小?经典叙述将"含所有方向线段的集合面积可趋零"直接作为集合属性陈述(Besicovitch 1928; Cunningham 1971),未显式申明"面积从哪来""升维靠什么操作"。本文提出欧氏几何的一个亚科——动态欧氏几何(Dynamic Euclidean Geometry),显式化三条新增公理:面积唯一来源是法向移动操作(旋转或沿法向平移);手性为所有刚体操作的经常属性;Perron tree 类构造中方向区间二分须沿扇区径向射线(径向分割刚性),高维中此条件不满足导致压缩机制断裂,即黏性公理的几何来源。本文指出经典叙述中"含所有方向线段的集合面积可趋零"隐含了未申明的操作链(旋转产生面积 + 平移压缩残余),若剥离该操作链则线段集合本身零面积。文末提出若干待决课题:若线段被赋予方向(向量化)空间结构可能改变;手性随维度增加的规律;过程手性(procedural chirality)的形式化度量。 English Abstract Starting from the Kakeya conjecture, this paper explores the practical significance and long-term impact of establishing, developing, and refining a sub-discipline of Euclidean geometry—Dynamic Euclidean Geometry. Classical Euclidean geometry (Euclid's Elements; Hilbert's Grundlagen der Geometrie, 1899) establishes incidence, congruence, parallelism, and continuity to describe static figures. The Kakeya problem (1907) and its Besicovitch–Perron construction (1928) involve dimensional dynamic upgrade: how a one-dimensional unit line segment becomes a two-dimensional covering containing segments in all directions, and how small this covering's measure can be. Classical accounts state "a set containing unit segments in all directions can have arbitrarily small measure" (Besicovitch 1928; Cunningham 1971) as an intrinsic set property, without explicitly declaring where area comes from or by what operation dimensional upgrade occurs. This paper proposes Dynamic Euclidean Geometry, formalizing three supplementary axioms: (A6) area is exclusively generated by normal translation (rotation about an endpoint or translation normal to the segment); (A7) chirality is a frequent attribute of all rigid operations; (A8) in Perron-tree-type constructions directional bisection must follow radial rays of the sector (radial subdivision rigidity), failing in higher dimensions due to insufficient normal degrees of freedom—this failure is the geometric origin of the stickiness axiom (Katz–Tao 2002). The paper further states the author's proposition that rotational area cannot be completely eliminated by translational compression—a conclusion from analyzing the Kakeya conjecture, presented for scholarly examination. Open questions are proposed: if line segments are endowed with direction (vectorization), spatial structure may change; how chirality increases with dimension; and the formalization of procedural chirality.
zhigang zhang (Fri,) studied this question.