The Passivity Architecture on the Bench: A Collision-Model Test in Circuit QED

Abraham J. Letter

Published Aug 5, 2026• 0 citations

Abstract

A companion programme derives an uncertainty floor, no-signalling, and the Clausius relation from one clause: all access is mediated by fresh cells of a finite, passive (KMS) sector. Whatever its fundamental status, that clause makes five sharp, testable claims about a laboratory system with the same architecture — a long-lived oscillator accessed only through a stream of ancilla qubits. We propose a circuit-QED realisation and specify all five with quantitative targets, from a coupling-independent estimation floor to a Bell frontier reaching 2√2 at zero demon work. Requirements sit within demonstrated capability. Keywords: circuit QED, collision models, quantum thermodynamics, Maxwell's demon, uncertainty relations, Bell inequalities, open quantum systems, experimental proposal, quant-ph

DOI: 10.5281/zenodo.21537260

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