A 69$ Minimal Physical Cancer Simulator for Testing Thermodynamic Irreversibility

We present a sub-$100 physical simulator that experimentally falsifies the Thermodynamic Necessity Argument (TNA) in oncology. A Raspberry-Pi-driven RC circuit with tunable dissipation, memory and noisy feedback reproduces the Ψ-control parameter previously derived for tumour tissue. When Ψ falls below the analytical threshold Ψ_crit = 1, forward–reverse voltage trajectories develop a finite, irreducible error, proving that local control alone cannot restore the initial state. The same topology maps quantitatively to cancer: clearance rate → dissipation, epigenetic distortion → memory, mutational+micro-environmental noise → σ. Thus, late-stage tumours are not “resistant”; they have crossed a phase-transition where tissue-level reversibility is physically impossible. The kit provides a 30-min, open-hardware assay that predicts—before therapy—whether a lesion can still be cured or only managed. “If irreversibility emerges in the simplest physically admissible system, complexity cannot be invoked as an explanation — only as an accelerator.”