The Parallelism Tradeoff: Limitations of Log-Precision Transformers William Merrill author Ashish Sabharwal author 2023 text journal article Transactions of the Association for Computational Linguistics continuing MIT Press Cambridge, MA periodical academic journal merrill-sabharwal-2023-parallelism 10.1162/tacl_a_00562 https://aclanthology.org/2023.tacl-1.31/ 2023 11 531 545