Modern large language models - transformers and diffusion language models - are built around two canonical algorithmic tasks: prediction and generation. We prove unconditional separations between low-depth quantum computation and the corresponding bounded-resource classical language-model architectures in both regimes.
The paper introduces the Quantum Scrambling Born Machine, a quantum generative model that uses a fixed entangling unitary—acting as a scrambling reservoir—to generate multi‑qubit entanglement while only optimizing single‑qubit rotations. Three types of entanglers are examined: a Haar random unitary, a finite‑depth brickwork random circuit, and analog time evolution under nearest‑neighbor spin‑chain Hamiltonians. The study finds that once the entangler achieves near‑Haar‑typical entanglement, the model can learn benchmark distributions with little sensitivity to the specific scrambler, and that making the Hamiltonian couplings trainable turns the task into a variational Hamiltonian problem with performance competitive with classical generative models at comparable parameter counts.
By Marcin P{\l}odzie\'n
arXiv:2608. 03962v1 Announce Type: cross Abstract: Modern large language models - transformers and diffusion language models - are built around two canonical algorithmic tasks: prediction and generation.
By Srinivasan Arunachalam, Arkopal Dutt, Hari Krovi, Rik Sengupta
arXiv:2604. 01197v4 Announce Type: replace-cross Abstract: Learning quantum states from measurement data is a central problem in quantum information and computational complexity.
By Fangjun Hu, Christian Kokail, Milan Kornja\v{c}a, Pedro L. S. Lopes, Weiyuan Gong, Sheng-Tao Wang, Xun Gao, Stefan Ostermann
arXiv:2608. 19306v1 Announce Type: cross Abstract: Given a set of input states, we consider the task of predicting the expectation value of a Pauli observable at the output of an unknown quantum evolution, using only a limited number of measurements.
By Jonas J\"ager, Yaroslav Khmelnitskiy, Paolo Braccia, Artur Miroszewski, Diego Garc\'ia-Mart\'in, M. Cerezo, Piotr Czarnik
arXiv:2401. 07039v5 Announce Type: replace-cross Abstract: Mixed quantum states are the native description of many physically important quantum systems, making their generation a fundamental task in quantum information processing.
By Chuangtao Chen, Qinglin Zhao, MengChu Zhou, Zhimin He, Zhili Sun, Haozhen Situ