The hyperbolicity of a model for relativistic extended thermodynamics of polyatomic gases is here proved for every time direction \(\xi _\alpha \); moreover, an expression for the production terms of the field equation is proposed which encloses as particular cases the variant of the Anderson–Witting model already known in the literature, but also a new variant of the Marle model. With these expressions, it is shown that the field equations satisfy automatically the requirement of a non-negative entropy production.

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相对论扩展热力学中多原子气体模型的双曲性

在每个时间方向\（\ xi _ \ alpha \）上证明了多原子气体的相对论性扩展热力学模型的双曲性；此外，提出了场方程生产项的表达式，在特定情况下，该表达式包含了文献中已知的安德森-维廷模型的变体，但也包含了马尔模型的新变体。通过这些表达式可以看出，场方程自动满足了非负熵产生的要求。