发表机构
Center for Theoretical Physics, Polish Academy of Sciences(波兰科学院理论物理中心)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
该论文证明对于偶次齐次势(指数为2k,k≥2),中心构型存在大量连续族,与牛顿情形(指数-1)的有限性形成对比,机制基于球面设计。
AI 中文摘要
我们研究通过成对势 \\[ U_\sigma = \frac{\kappa}{\sigma} \sum_{i<j}m_i m_j r_{ij}^{\sigma} \\] 相互作用的 $n$ 个天体的中心构型,其中在 $\sigma=0$ 处取对数极限。对于牛顿指数 $\sigma=-1$,经典的 Chazy--Wintner--Smale 有限性问题询问:对于给定的正质量,是否存在仅有限多个中心构型(在相似意义下)。已知在若干重要的特殊情形以及额外的维度或一般性假设下,有限性成立。因此,自然要问:类似的有限性原理是否对其他齐次指数仍然成立。我们证明,对于每个正偶指数 \\[ \sigma=2k, \qquad k\ge2, \\] 答案是明确否定的。事实上,这些指数允许大量成对不相似的中心构型的连续族。其机制由球面设计提供:在公共球面上,$\sigma=2k$ 的力核限制为次数至多 $k$ 的多项式,因此每个正加权球面 $k$-设计都是中心构型。我们显式计算了相应的中心乘子。
英文摘要
We study central configurations for $n$ bodies interacting through pair potentials \[ U_σ = \fracκσ \sum_{i<j}m_i m_j r_{ij}^σ, \] with logarithmic limit at $σ=0$. For the Newtonian exponent $σ=-1$, the classical Chazy--Wintner--Smale finiteness problem asks whether, for prescribed positive masses, there are only finitely many central configurations up to similarity. Finiteness is known in several important special cases and under additional dimensional or genericity hypotheses. It is therefore natural to ask whether an analogous finiteness principle continues to hold for other homogeneous exponents. We show that for every positive even exponent \[ σ=2k, \qquad k\ge2, \] the answer is emphatically negative. In fact, these exponents admit an abundance of continuous families of pairwise non-similar central configurations. The mechanism is provided by spherical designs: on a common sphere the force kernel for $σ=2k$ restricts to a polynomial of degree at most $k$, and consequently every positive weighted spherical $k$-design is a central configuration. We compute the corresponding central multiplier explicitly.