The Physics of Learning: How Race-Architecture Constraints Explain What We Know About Teaching, Communication, and Understanding

Three of learning science's most robust traditions, cognitive load theory, desirable difficulties, and psychological safety, are each empirically excellent and mechanically thin. This paper argues they are local consequences of one substrate-universal constraint, bounded-capacity race-architecture, and translates that mechanics to human learning, teaching, and communication for audiences in education research, instructional design, and organisational psychology. Abstract. Three traditions of learning science — cognitive load theory and multimedia learning (Sweller, Mayer); desirable difficulties and retrieval practice (Bjork, Roediger, Karpicke); psychological safety and need-prepotency (Maslow, Edmondson) — are each empirically excellent and mechanically thin. They terminate at cognitive-architecture-as-given, representational-properties-as-given, and behavioural-information-flow-as-given. This paper proposes that the three are local consequences of the same substrate-universal physical constraints: bounded-capacity race-architecture, friction as the cost of unresolved competing routes, hysteresis as encoding-through-loading, and the Net Friction Rule as integrated-friction optimisation. The substrate-level account is empirically anchored by language-model substrates where the mechanism is mechanically visible, and the same constraints derive, rather than postulate, working-memory limits, the testing effect, the spacing effect, expertise reversal, and prepotency of safety-field activity over substantive-content processing. Implications for curriculum design, moment-by-moment classroom diagnosis, technical and organisational communication, and change management are developed. Four falsification conditions are specified. v3 changelog (June 2026). v3 integrates the Friction-Theory measurement cluster as didactic enrichments grounded in companion findings: commit-pressure as an annealing temperature and the “give them time” lever (§3.2, §7.3); chunking as an architecture × task × capacity dissociation (§3.4, §5.4); purpose-framing and the disposition-versus-proposition installation distinction (§6.2b); over-drilling and its critical-slowing-down precursor (§7.4b); a depth-of-commitment phase-transition signature of over-capacity friction (§7.2); and a substrate-level account of the Dunning-Kruger curve as the default shape of confidence-as-route-competition, with a learned meta-confidence modulator predicting individual differences and a base-versus-instruction-tuned contrast (§8.6). New prior-art engagement includes Kruger & Dunning (1999), Gignac & Zajenkowski (2020), Tian et al. (2023) on alignment-tuning and calibration, Rowe (1986) on wait-time, and Wood, Bruner & Ross (1976) on scaffolding. The v3 additions went through external dual hostile peer-review. Builds on the v2 revision (seven-round dual review; §6.5 modality-precision, §8.8 communication-versus-application, §9.6 scope-and-collaboration). Companion papers in the Friction Theory series (Zenodo-live): Paper 0 (Behavioural Friction Theory): 10.5281/zenodo.19462499; Paper 1 (Friction Theory substrate): 10.5281/zenodo.20012654; Paper 4 (LLM calibration): 10.5281/zenodo.20059859; Paper 4B (Substrates encode experience): 10.5281/zenodo.20059861; Paper 6 (Matched friction under hysteresis): 10.5281/zenodo.20059863; Paper 7 (Forward-modelling in bounded race substrates): 10.5281/zenodo.20449154; Paper 8 (Pressure, Hysteresis, and Experience): 10.5281/zenodo.20059865; Paper 13 (Operational Friction Theory): 10.5281/zenodo.20059876; and the measurement cluster — Paper 2D: 10.5281/zenodo.20562084; Paper 4C: 10.5281/zenodo.20562086; Paper 4D: 10.5281/zenodo.20562088; Paper 2E: 10.5281/zenodo.20562090; Paper 21: 10.5281/zenodo.20562415. Series position. Paper 16 in the Friction Theory paper-series. Target venue: Mind, Brain, and Education (Wiley/IMBES; primary) / Educational Psychology Review (secondary) / Educational Theory (tertiary).