Keio University · 물리·천문학
Ryo Yokokura 교수의 연구실은 3+1차원 양자장론에서의 고차원 대칭성과 고차원 군 구조, 특히 축축한(axion) 전자기계와의 결합을 중심으로 한 상대론적 양자장 이론의 수학적 구조를 연구합니다. 주요 관심사는 고차원 전이 대칭성, 비가역적 대칭성, 그리고 3-군(3-group) 또는 4-군(4-group)과 같은 고차원 대칭군의 기하학적·(topological) 구조입니다. 이는 양자홀효과, 위튼 효과, 분수 전하 생성, 그리고 토폴로지적 순서 등 다양한 양자현상을 기술하는 데 기여합니다. 특히, 상전이, 토폴로지적 장 이론, 't Hooft 이상 등에서 나타나는 비가역적 대칭성과 그 물리적 결과를 깊이 있게 분석합니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
We study higher-form symmetries in a low-energy effective theory of a massless axion coupled with a photon in (3+1) dimensions. It is shown that the higher-form symmetries of this system are accompanied by a semistrict 3-group (2-crossed module) structure, which can be found by the correlation functions of symmetry generators of the higher-form symmetries. We argue that the Witten effect and anomalous Hall effect in the axion electrodynamics can be described in terms of 3-group transformations.
We study higher-form global symmetries and a higher-group structure of a low-energy limit of $(3+1)$-dimensional axion electrodynamics in a gapped phase described by a topological action. We argue that the higher-form symmetries should have a semi-strict 4-group (3-crossed module) structure by consistency conditions of couplings of the topological action to background gauge fields for the higher-form symmetries. We find possible 't Hooft anomalies for the 4-group global symmetry, and discuss phy
We study non-invertible global symmetries in $(3+1)$-dimensional axion electrodynamics with a massless axion and a massless photon. In addition to a previously known non-invertible 0-form shift symmetry of the axion, we find a non-invertible 1-form symmetry associated with the equation of motion for the photon. Correlation functions of non-invertible symmetry defects lead to invertible 1- and 2-form symmetry defects associated with Bianchi identities for the axion and photon. In terms of the cor
We show that axion models with the domain wall number k in (3+1) dimensions, i.e., periodic scalar field theories admitting k axion domain walls, exhibit an emergent Zk 3-form symmetry for k>1 in addition to a conventional Zk 0-form symmetry. The emergent 3-form symmetry is explicitly shown by establishing a low-energy dual transformation between the scalar field theory and a 3-form gauge theory. We further argue that the emergent 3-form symmetry is spontaneously broken, and the breaking pattern
A bstract We demonstrate a universal mechanism of a class of instabilities in infrared regions for massless Abelian p -form gauge theories with topological interactions, which we call generalized chiral instabilities. Such instabilities occur in the presence of initial electric fields for the p -form gauge fields. We show that the dynamically generated magnetic fields tend to decrease the initial electric fields and result in configurations with linking numbers, which can be characterized by non
We study higher-form symmetries and a higher group in the low energy limit of a (3+1)-dimensional axion electrodynamics with a massive axion and a massive photon. A topological field theory describing topological excitations with the axion-photon coupling, which we call a topological axion electrodynamics, is obtained in the low energy limit. Higher-form symmetries of the topological axion electrodynamics are specified by equations of motion and Bianchi identities. We find that there are induced
