English

Gauge Is More Than Mathematical Redundancy

High Energy Physics - Theory 2021-04-14 v1 History and Philosophy of Physics

Abstract

Physical systems may couple to other systems through variables that are not gauge invariant. When we split a gauge system into two subsystems, the gauge-invariant variables of the two subsystems have less information than the gauge invariant variables of the original system; the missing information regards degrees of freedom that express relations between the subsystems. All this shows that gauge invariance is a formalization of the relational nature of physical degrees of freedom. The recent developments on boundary variables and boundary charges are clarified by this observation.

Keywords

Cite

@article{arxiv.2009.10362,
  title  = {Gauge Is More Than Mathematical Redundancy},
  author = {Carlo Rovelli},
  journal= {arXiv preprint arXiv:2009.10362},
  year   = {2021}
}

Comments

3 pages. To appear in the proceedings of the conference "One Hundred Years of Gauge Theory, Bad Honnef 2018", S. De Bianchi and C. Kiefer eds

R2 v1 2026-06-23T18:42:39.819Z