Scalable approach to many-body localization via quantum data. - Alexander Gresch; Lennart Bittel; Martin Kliesch (CoRR, 2022)

Optimizing the depth of variational quantum algorithms is strongly QCMA-hard to approximate. - Lennart Bittel; Sevag Gharibian; Martin Kliesch (CoRR, 2022)

The Optimal Depth of Variational Quantum Algorithms Is QCMA-Hard to Approximate. - Lennart Bittel; Sevag Gharibian; Martin Kliesch (CCC, 2023)

PAC-learning of free-fermionic states is NP-hard. - Lennart Bittel; Antonio Anna Mele; Jens Eisert; Lorenzo Leone (Quantum, 2025)

Optimal estimates of trace distance between bosonic Gaussian states and applications to learning. - Lennart Bittel; Francesco Anna Mele; Antonio Anna Mele; Salvatore Tirone; Ludovico Lami (Quantum, 2025)