In the study of Babel.
Lucien was lying in his armchair with his eyes closed. In front of him, there was a glass of water which had not been touched. In fact, he was reading the quantum mechanics books in his spirit library, especially those regarding matrix mechanics. At the same time, he was also calculating something.
Even for Lucien right now, matrix mechanics was very difficult. It required lots of patience and perseverance to dig in, and its coldness and complexity could easily drive away any beginners.
Lucien could have first thrown out matter waves and then Schrödinger equation. In this way, he could use a much easier way which was more familiar to most arcanists, especially those in the school of electromagnetics and light-darkness, to start introducing wave mechanics. Wave mechanics was also a major branch of quantum mechanics, and it could solve most problems in the current new alchemy system.