Why Gauge?
High Energy Physics - Theory
2016-07-06 v2 General Relativity and Quantum Cosmology
Abstract
The world appears to be well described by gauge theories; why? I suggest that gauge is more than mathematical redundancy. Gauge-dependent quantities can not be predicted, but there is a sense in which they can be measured. They describe "handles" though which systems couple: they represent real relational structures to which the experimentalist has access in measurement by supplying one of the relata in the measurement procedure itself. This observation leads to a physical interpretation for the ubiquity of gauge: it is a consequence of a relational structure of physical quantities.
Cite
@article{arxiv.1308.5599,
title = {Why Gauge?},
author = {Carlo Rovelli},
journal= {arXiv preprint arXiv:1308.5599},
year = {2016}
}
Comments
8 pages (references added)