Symmetries and currents of massless neutrino fields, electromagnetic and graviton fields

共形对称性下德西特时空中引力子、“部分无质量”引力子与光子场的统一框架

A unified framework for graviton, "partially massless" graviton, and photon fields in de Sitter spacetime under conformal symmetry

本文基于Dirac六锥形式体系和Wigner群论分析，在德西特时空中建立共形不变框架，统一描述引力子、“部分无质量”引力子及光子场。

Graviton in a Curved Space-Time Background and Gauge Symmetry

Pauli-Fierz approach to description of a massless spin-2 particle is investigated in the framework of 30-component first order relativistic wave equation theory on a curved space-time background. It is shown that additional gauge symmetry of massless equations established by Pauli-Fierz can be extended only to curved space-time regions where Ricci tensor vanishes. In all such space-time models the generally covariant S=2 massless wave equation exhibits gauge symmetry property, otherwise it is not so.

德西特时空中部分无质量引力子场的协变量子化

Covariant Quantization of the Partially Massless Graviton Field in de Sitter Spacetime

本文基于德西特群表示论和Wightman-Gärding公理，利用坐标无关的德西特平面波对部分无质量引力子场进行协变量子化，给出满足定域性、协变性和正规解析性的两点函数，并证实其光锥传播性质。

Lagrange Anchor and Characteristic Symmetries of Free Massless Fields

A Poincaré covariant Lagrange anchor is found for the non-Lagrangian relativistic wave equations of Bargmann and Wigner describing free massless fields of spin $s>1/2$ in four-dimensional Minkowski space. By making use of this Lagrange anchor, we assign a symmetry to each conservation law and perform the path-integral quantization of the theory.

Generalized Symmetries of Massless Free Fields on Minkowski Space

A complete and explicit classification of generalized, or local, symmetries of massless free fields of spin $s \geq 1/2$ is carried out. Up to equivalence, these are found to consists of the conformal symmetries and their duals, new chiral symmetries of order $2s$, and their higher-order extensions obtained by Lie differentiation with respect to conformal Killing vectors. In particular, the results yield a complete classification of generalized symmetries of the Dirac-Weyl neutrino equation, Maxwell's equations, and the linearized gravity equations.

Symmetries of Massive and Massless Neutrinos

Wigner's little groups are subgroups of the Lorentz group dictating the internal space-time symmetries of massive and massless particles. These little groups are like O(3) and E(2) for massive and massless particles respectively. While the geometry of the O(3) symmetry is familiar to us, the geometry of the flat plane cannot explain the E(2)-like symmetry for massless particles. However, the geometry of a circular cylinder can explain the symmetry with the helicity and gauge degrees of freedom. It is shown further that the symmetry of the massless particle can be obtained as a zero-mass limit …