近日， 北京大学物理学院的陈斌及其研究小组与清华大学的Reiko Liu合作并取得一项新进展。经过不懈努力，他们成功根据零约化构造出Carrollian场理论。相关研究成果已于2023年11月24日在国际知名学术期刊《高能物理杂志》上发表。

本文通过研究d+1维中Bargmann不变作用的零约化，提出了一种全新的方法来构建d维Carrollian场理论的脱壳作用。该方法基于这样一个事实，即d维Carrollian对称实际上是(d+1)维Bargmann对称在零超曲面上的限制。研究人员重点探论了自由标量场理论和电磁场理论，并证明这些理论的电扇区和磁扇区均源于一个高维的独特的Bargmann不变量作用。

针对无质量自由标量场和d=4的电磁场，研究人员验证了所得理论的Carrollian共形不变性，并揭示了Carrollian共形代数中自然存在的链式表示和交错模。

附：英文原文

Title: Constructing Carrollian field theories from null reduction

Author: Chen, Bin, Liu, Reiko, Sun, Haowei, Zheng, Yu-fan

Issue&Volume: 2023-11-24

Abstract: In this paper, we propose a novel way to construct off-shell actions of d-dimensional Carrollian field theories by considering the null-reduction of the Bargmann invariant actions in d +1 dimensions. This is based on the fact that d-dimensional Carrollian symmetry is the restriction of the (d + 1)-dimensional Bargmann symmetry to a null hypersurface. We focus on free scalar field theory and electromagnetic field theory, and show that the electric sectors and the magnetic sectors of these theories originate from different Bargmann invariant actions in one higher dimension. In the cases of massless free scalar field and d = 4 electromagnetic field, we verify the Carrollian conformal invariance of the resulting theories, and find that there appear naturally chain representations and staggered modules of Carrollian conformal algebra.

DOI: 10.1007/JHEP11(2023)170

Source: https://link.springer.com/article/10.1007/JHEP11(2023)170