The Revolutionary Beginner's Guide to Quantum Computing: Why We Don't Have Quantum Computers Yet — and What the Geometric Alternative Offers

A 20-chapter beginner's guide to quantum computing that starts with an honest question — why don't we have quantum computers yet? The guide teaches the standard curriculum accurately, explains why the standard approach faces a thermodynamic wall (a 20,000-fold cooling gap that is Carnot-limited), and introduces the ultrametric alternative: passive geometric fault tolerance on Bruhat-Tits trees, with DOI-registered evidence, computationally validated error thresholds 75 times higher than surface codes, and three falsifiable predictions. This is the v1.2 edition (August 2026). Five quantitative statements from the May 2026 edition are corrected, each verified by an independent computation deposited with this record (artifacts/verification/verify_guide_claims.py, 35 checks, all passing; see Appendix B). Appendix A records the research program's progress since May 2026, including a trapped-ion falsifiability register, an audit of a 2026 no-go theorem on quantum error correction and quantum Darwinism, and the program's own correction on prime-valuation readings of quantum codes. This deposit includes the complete source set: manuscript, HTML, PDF, references (BibTeX), citation audit, project plan, license, and verification artifacts. v1.2.1 (August 2026): post-publication audit corrections. Chapter 20's summary now lists seven open problems (including the QEC–Darwinism tradeoff); the LHC temperature comparison is marked approximate (95×, rounded); Appendix A correction #5 completed; the citation audit's internal-reference count corrected; open problem 7 carries its numeric bound (F_L > 0.874). No quantitative claims changed. v1.2.2 (August 2026): deposit-file corrections. LICENSE now contains the full CC BY 4.0 International legal code, and README.md is the deposit manifest (a project-blueprint README was attached in v1.2.1 by an automation error). No content changes.