Real-world computers have operational constraints that cause nonzero entropy production (EP). In particular, almost all real-world computers are ‘periodic’, iteratively undergoing the same physical process; and ‘local’, in that subsystems evolve whilst physically decoupled from the rest of the computer. These constraints are so universal because decomposing a complex computation into small, iterative calculations is what makes computers so powerful. We first derive the nonzero EP caused by the locality and periodicity constraints for deterministic finite automata (DFA), a foundational system of computer science theory. We then relate this minimal EP to the computational characteristics of the DFA. We thus divide the languages recognised by DFA into two classes: those that can be recognised with zero EP, and those that necessarily have non-zero EP. We also demonstrate the thermodynamic advantages of implementing a DFA with a physical process that is agnostic about the inputs that it processes.
This content will become publicly available on May 1, 2025
- Award ID(s):
- 2221345
- PAR ID:
- 10508759
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review X
- Volume:
- 14
- Issue:
- 2
- ISSN:
- 2160-3308
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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