We show that self-interacting vector field theories exhibit unphysical behavior even when they are not coupled to any external field. This means any theory featuring such vectors is in danger of being unphysical, an alarming prospect for many proposals in cosmology, gravity, high energy physics, and beyond. The problem arises when vector fields with healthy configurations naturally reach a point where time evolution is mathematically ill defined. We develop tools to easily identify this issue, and provide a simple and unifying framework to investigate it.

中文翻译：

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自交互向量场的内在病理学

我们表明，自相互作用矢量场理论即使不与任何外部场耦合，也会表现出非物理行为。这意味着任何以此类向量为特征的理论都存在非物理的危险，对于宇宙学、引力、高能物理学等领域的许多提议来说，这是一个令人担忧的前景。当具有健康配置的向量场自然地达到时间演化在数学上定义不明确的点时，就会出现问题。我们开发工具来轻松识别此问题，并提供一个简单而统一的框架来调查它。