A PRNG key is an explicit data object identifying the deterministic state used by a pseudo-random operation. JAX passes it explicitly instead of relying on global seed state. section 3.5.3
Create and reuse a key
Create a key with jax$random$key(123L), then pass it as the first argument to jax$random$normal(). Reusing the same key produces the same value each time. section 3.5.3
Split a key for new randomness
Use jax$random$split(seed_key, num = 1L)@py[0] to derive a new key. The split is deterministic, so the same sequence of splits produces the same resulting key. section 3.5.3


