Leptogenesis mechanism for cosmic matter-antimatter asymmetry

The cosmic matter-antimatter asymmetry is one of the core puzzles in the interdisciplinary field of modern particle physics and cosmology, attracting intense attention from the academic community for a long time. The leptogenesis mechanism has emerged as a mainstream candidate for explaining this puzzle, owing to its unique advantage of unifying the origin of non-zero neutrino masses with the cosmic matter-antimatter asymmetry. This review comprehensively summarizes the current status and frontier progress of the leptogenesis mechanism: it first briefly reviews the research background, then focuses on elaborating the basic theory and phenomenological consequences of standard leptogenesis based on the Type-I seesaw model. Subsequently, it systematically discusses various non-standard implementation pathways, including resonant leptogenesis, ARS leptogenesis, Higgs decay leptogenesis, Dirac leptogenesis, leptoflavorgenesis, spontaneous leptogenesis, wash-in leptogenesis, Affleck-Dine leptogenesis, and phase transition-triggered leptogenesis. Furthermore, it details the specific implementations and phenomenological characteristics of leptogenesis in various new physics models, such as Inverse and Linear seesaw models, scalar singlet-extended seesaw models, Scotogenic models, Type-II/III seesaw models, left-right symmetric models, SO(10) grand unified theories, and supersymmetric models. It also deeply analyzes the intrinsic connections between leptogenesis and cosmological phenomena such as inflation, gravitational fields, black hole evaporation, and dark matter asymmetry. Finally, it outlines the feasibility of testing the leptogenesis mechanism through direct detection, indirect detection, cosmological observations, and reverse falsification, providing a comprehensive and systematic reference for future research in this field.