Based on three common interpretive commitments in general relativity, I raise a conceptual problem for the usual identification, in that theory, of timelike curves as those that represent the possible histories of (test) particles in spacetime. This problem affords at least three different solutions, depending on different representational and ontological assumptions one makes about the nature of (test) particles, fields, and their modal structure. While I advocate for a cautious pluralism regarding these options, I also suggest that re-interpreting (test) particles as field processes offers the most promising route for natural integration with the physics of material phenomena, including quantum theory.

中文翻译：

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哪些世界线代表可能的粒子历史？

基于广义相对论中的三个常见解释承诺，我提出了一个概念问题，用于在该理论中通常将类时曲线识别为代表时空（测试）粒子可能历史的曲线。这个问题至少提供了三种不同的解决方案，这取决于人们对（测试）粒子、场及其模态结构的性质所做的不同表征和本体论假设。虽然我主张对这些选项采取谨慎的多元化，但我也建议将（测试）粒子重新解释为场过程，为与材料现象物理学（包括量子理论）的自然整合提供了最有希望的途径。