4 papers
Hierarchical Axiverse
Hai-Jun Li
String compactifications generically produce light axion-like particles, yet low-energy mixing has not previously been exploited as a structuring constraint on thei…
Stochastic Axion Mixing: A General Mechanism Beyond Decay Constant Constraints
Hai-Jun Li
We propose a novel and generalized mechanism, dubbed stochastic axion mixing. In a multi-axion framework, this mixing occurs naturally provided that the masses of all ultra-light a…
Some Properties of Multi-Component Axion Dark Matter
Hai-Jun Li
We introduce a mechanism for multi-component dark matter (DM) that originates from axion mixing and present some of its defining properties. In this context, multi-component DM imp…
Toward the Effective Light and Heavy QCD Axion Scenarios
Hai-Jun Li
In this work, we investigate the effective parameter space associated with the axion mass and the axion decay constant in both the light and heavy QCD axion scenarios. We initiate…