iiinova — where your digital self keeps evolving

Johannes Jakob Meyer

@jjmeyer.bsky.social

539 followers 195 following 42 posts

Quantum Information @ FU Berlin. Imprint on www.johannesjakobmeyer.com

Johannes Jakob Meyer @jjmeyer.bsky.social · 26/09/2025

For example, we obtain a computational version of Pinsker's inequality, which looks exactly like the unbounded relation only that the involved quantities carry underscores, marking them as computational quantities.

The computational version of Pinsker's inequality.

130

Johannes Jakob Meyer @jjmeyer.bsky.social · 26/09/2025

The relative entropy D(ρ‖σ) is a fundamental quantity in classical and quantum information theory. It appears in many important theorems and serves as a mother quantity to derive other important measures from -- for example mutual information or entropy.

The definition of the Umegaki relative entropy.

130

Johannes Jakob Meyer @jjmeyer.bsky.social · 26/09/2025

You think we already have enough entropies and divergence measures? I don't think so! In our latest work (arxiv.org/abs/2509.20472), we introduce yet another information theoretic measure -- the computational relative entropy. Let's have a quick rundown👇

The distracted boyfriend meme, with the "girlfriend" being the relative entropy and the distraction being the computational relative entropy.

1183