The Power of Hard Attention Transformers on Data Sequences: A Formal Language Theoretic Perspective Chris Köcher RPTU Kaiserslautern-Landau

Neural Information Processing Systems 

Formal language theory has recently been successfully employed to unravel the power of transformer encoders. This setting is primarily applicable in Natural Language Processing (NLP), as a token embedding function (where a bounded number of tokens is admitted) is first applied before feeding the input to the transformer.