6 papers
Spacelike reduction of the gravitational topological terms and associated helicity densities
Hongxi Huang, Jiang Long, Gan Zhao +1
Helicity in gravity is a multifaceted concept, and several inequivalent definitions exist in the literature. In this work, we reduce the topological Pontryagin and Nieh-Yan terms t…
Spinning bulk-to-boundary correlators in the massless theories with Poincaré symmetry
Jiang Long, Yu-Xuan Wei, Xin-Hao Zhou
We classify the bulk-to-boundary correlators for general integer-spin operators in a Poincaré-invariant theory by imposing suitable fall-off conditions near future/past null in…
Reduction of topological invariants on null hypersurfaces
Jiang Long, Xin-Hao Zhou
Gravitational helicity flux density represents the angular distribution of helicity flux in general relativity. In this work, we explore its relationship to the reduction of topolo…
Electromagnetic helicity flux density for radiative systems
Zhen-Yu Heng, Jiang Long, Run-Ze Yu +1
We show that the helicity flux density is distinguished from magnetic helicity by analysing Hopf solitons. The electromagnetic (EM) helicity flux and the magnetic helicity are Cher…
Electromagnetic helicity flux operators in higher dimensions
Wen-Bin Liu, Jiang Long, Xin-Hao Zhou
The helicity flux operator is a fascinating quantity that characterizes the angular distribution of the helicity of radiative photons or gravitons and it has many interesting physi…
Quantum flux operators in higher spin theories
Wen-Bin Liu, Jiang Long, Xin-Hao Zhou
We construct Carrollian higher spin field theories by reducing the bosonic Fronsdal theories in flat spacetime to future null infinity. We extend the Poincaré fluxes to quantum flu…