Quickly? Redux is a state container that supports Flux actions and Elm is a language with a companion architecture that's recommended. The comparison would be between Elm and Javascript/Typescript+React+Redux, as it provides the ability to implement those featuresets out of the box, including Messages, which is the TEA answer to Redux and Flux actions (more or less).

Personally, I find working with Elm's state management features is like heaven compared to dealing with Redux+Typescript's intensely noisy types.