Thermodynamics of Present Records in FCLET Finite-Capacity Entropy, Landauer Cost, and Latency-Regulated Irreversibility

This article establishes the thermodynamics of present physical records in FCLET. A record is not a stored segment of time; it is a current physical configuration carrying information about causally prior events. Every record carrier possesses finite operational capacity, finite distinguishability, finite reserve, and a latency-regulated transition rate. The theory separates three quantities that must remain mathematically distinct: record information , combinatorial occupancy entropy , and irreversible entropy production . For a record system containing finite slots and occupied slots, and The number of occupancy configurations is and the large- combinatorial entropy is Finite capacity generates a thermodynamic filling potential which diverges as . In terms of FCLET load, Thus logarithmic capacity load is the dominant thermodynamic filling coordinate near saturation. The article derives the local first law, entropy balance, Landauer erasure bound, record-writing and erasure kinetics, detailed-balance invariance, latency-regulated power, fluctuation structure, and total entropy-production law. Universal latency multiplies forward and reverse transition rates by the same factor . It therefore slows kinetics while preserving their equilibrium ratio. In operational time, the canonical record master equation becomes independent of the common latency factor. The theory also proves that a stable stored record carries no universal mandatory continuous Landauer power. Thermodynamic cost attaches to physical writing, reset, logically irreversible overwrite, stabilization, error correction, and dissipation. This distinction prevents the identification of information storage with perpetual energy consumption. Present-record thermodynamics closes the FCLET chain from finite distinguishability to physical irreversibility: