The un-reduction procedure introduced previously in the context of classical mechanics is extended to covariant field theory. The new covariant un-reduction procedure is applied to the problem of shape matching of images which depend on more than one independent variable (for instance, time and an additional labelling parameter). Other possibilities are also explored: nonlinear $$\sigma $$σ-models and the hyperbolic flows of curves.

中文翻译：

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场论中的不归约

先前在经典力学背景下引入的非归约程序扩展到协变场论。新的协变不归约程序应用于依赖于多个自变量（例如，时间和附加标记参数）的图像形状匹配问题。还探讨了其他可能性：非线性 $$\sigma $$σ 模型和曲线的双曲流。