A classical system of conservation laws descriptive of relativistic gasdynamics is examined. In the two-dimensional stationary case, the system is shown to be invariant under a novel multi-parameter class of reciprocal transformations. The class of invariant transformations originally obtained by Bateman in non-relativistic gasdynamics in connection with lift and drag phenomena is retrieved as a reduction in the classical limit. In the general 3+1-dimensional case, it is demonstrated that Synge’s geometric characterization of the pressure being constant along streamlines encapsulates a three-dimensional extension of an integrable Heisenberg spin equation.

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关于相对论气体动力学：一类互易型变换和可积海森堡自旋连接下的不变性

研究了描述相对论气体动力学的经典守恒定律系统。在二维平稳的情况下，系统在一个新的互易变换的多参数类下被证明是不变的。最初由 Bateman 在与升力和阻力现象相关的非相对论气体动力学中获得的不变变换类被检索为经典极限的减少。在一般的 3+1 维情况下，证明了 Synge 对压力沿流线恒定的几何特征封装了可积海森堡自旋方程的三维扩展。