Modified instanton sum in QCD and higher-groups
Modified instanton sum in QCD and higher-groups
复制标题
DOI:
10.1007/jhep03(2020)123
复制
发表时间:
2019-12
影响因子:
5.4
通讯作者:
Y. Tanizaki;M. Ünsal
中科院分区:
文献类型:
--
作者:
Y. Tanizaki;M. Ünsal
We consider the SU (N) Yang-Mills theory, whose topological sectors are restricted to the instanton number with integer multiples of p. We can formulate such a quantum field theory maintaining locality and unitarity, and the model contains both 2π-periodic scalar and 3-form gauge fields. This can be interpreted as coupling a topological theory to Yang-Mills theory, so the local dynamics becomes identical with that of pure Yang-Mills theory. The theory has not only ℤ N 1-form symmetry but also ℤ p 3-form symmetry, and we study the global nature of this theory from the recent’t Hooft anomaly matching. The computation of’t Hooft anomaly incorporates an intriguing higher-group structure. We also carefully examine that how such kinematical constraint is realized in the dynamics by using the large-N and also the reliable semiclassics on ℝ 3× S 1, and we find that the topological susceptibility plays a role of the order parameter for the ℤ p 3-form symmetry. Introducing a fermion in the fundamental or adjoint representation, we find that the chiral symmetry becomes larger than the usual case by ℤ p, and it leads to the extra p vacua by discrete chiral symmetry breaking. No dynamical domain wall can interpolate those extra vacua since such objects must be charged under the 3-form symmetry in order to match the’t Hooft anomaly.