近日，法国国家科学研究中心Sucheta Majumdar团队研究了洛伦兹光锥理论中的卡罗尔推论。相关论文发表在2026年2月26日出版的《高能物理杂志》上。

研究组通过闵可夫斯基时空中的零约化，从洛伦兹光锥作用量推导出卡罗尔场论。通过适当形变光锥作用量，将庞加莱不变性约化为巴格曼子群，从而在低一维空间中同时得到磁卡罗尔作用和电卡罗尔作用。通过正则分析表明，这些形变后的巴格曼不变作用量不存在洛伦兹光锥理论中常见的第二类约束。

研究组分别演示了有无规范对称性理论的推导过程。值得注意的是，磁卡罗尔部分可直接从原始洛伦兹作用量导出，而电卡罗尔部分的获得则必须借助形变。进一步论证表明，d维磁卡罗尔解构成(d+1)维母体洛伦兹理论解的一致截断，为零超曲面附近的光锥动力学提供了有效描述。对于规范理论，研究组还阐明了光锥规范条件在导出卡罗尔理论中的关键作用。

附：英文原文

Title: Carroll theories from Lorentzian light-cone theories

Author: Majumdar, Sucheta

Issue&Volume: 2026-02-26

Abstract: We derive Carrollian field theories via null reduction from Lorentzian light-cone actions in Minkowski spacetime. By suitably deforming the light-cone action, we reduce the Poincaré invariance to a Bargmann subgroup, from which both magnetic and electric Carroll actions can be obtained in one lower dimension. Through a canonical analysis, we show that the second-class constraints usually found in Lorentzian light-cone theories are absent for these deformed Bargmann-invariant actions. We demonstrate the procedure for theories with and without gauge symmetry. Notably, while the magnetic Carroll sector can be directly derived from the original Lorentzian action, the deformation is essential to obtain the electric Carroll sector. We further argue that magnetic Carroll solutions in d dimensions represent a consistent truncation of the solutions of the (d + 1)-dimensional Lorentzian parent theory, providing an effective description of light-cone dynamics near a null hypersurface. For gauge theories, we also highlight the role of the light-cone gauge condition in deriving Carrollian theories.

DOI: 10.1007/JHEP02(2026)258

Source: https://link.springer.com/article/10.1007/JHEP02(2026)258