Principles and symmetries of complexity in quantum field theory Run-Qiu Yang, Yu-Sen An, Chao Niu, Cheng-Yong Zhang and Keun-Young Kim Eur. Phys. J. C, 79 2 (2019) 109 Published online: 04 February 2019 DOI: 10.1140/epjc/s10052-019-6600-3