论文标题
关于离散的korteweg-devries方程的奇异性
On the singularities of the discrete Korteweg-deVries equation
论文作者
论文摘要
我们研究离散Korteweg-Devries(D-KDV)方程中的奇异性结构。确定了四种不同类型的奇点。第一种类型对应于本地化的“限制”,奇异性,其限制为D-KDV的概括提供了可集成性条件。另外两种类型的奇异性是无限的范围,由无限的倾斜线组成,可能与零线交替。第四种奇点对应于水平条,其中垂直相邻点上值的乘积等于1。由于其取向,这种奇异性实际上可以与其他类型相互作用。这为D-KDV的奇异性提供了极富丰富的结构,本文详细研究了该结构。鉴于第四类奇点起着重要的作用,我们决定给它一个特殊的名称:taishi(文本中解释了其起源)。 Taishi不存在D-KDV的不可整合的扩展,它在不可整合的情况下解释了奇异性结构的相对缺乏:与斜线相对应的第二和第三种类型的奇异性仍然存在,并且该集成案例的本地化象征性现在变得毫无条件地变得不合理,导致了半融合线的无限型无限型Zeros。
We study the structure of singularities in the discrete Korteweg-deVries (d-KdV) equation. Four different types of singularities are identified. The first type corresponds to localised, `confined', singularities, the confinement constraints for which provide the integrability conditions for generalisations of d-KdV. Two other types of singularities are of infinite extent and consist of oblique lines of infinities, possibly alternating with lines of zeros. The fourth type of singularity corresponds to horizontal strips where the product of the values on vertically adjacent points is equal to 1. (A vertical version of this singularity with product equal to $-1$ on horizontally adjacent sites also exists). Due to its orientation this singularity can, in fact, interact with the other types. This leads to an extremely rich structure for the singularities of d-KdV, which is studied in detail in this paper. Given the important role played by the fourth type of singularity we decided to give it a special name: taishi (the origin of which is explained in the text). The taishi do not exist for nonintegrable extensions of d-KdV, which explains the relative paucity of singularity structures in the nonintegrable case: the second and third type of singularities that correspond to oblique lines still exist and the localised singularities of the integrable case now become unconfined, leading to semi-infinite lines of infinities alternating with zeros.