JAEN

STUDIO TORIUMI / MULTIVERSE GUIDEBOOK

The universe might
not be just one.

マルチバース攻略本 (Multiverse Guidebook) is a 12-chapter guide to the multiverse, string theory and the many-worlds interpretation — written for readers without a physics background, with no equations from start to finish.

You don't just read it. You run the experiments. A double-slit simulator, a branching-worlds demo, and quizzes along the way; XP accumulates as you go. It reads like a game, and the whole thing is free.

The main text is written in Japanese. This page is a complete English introduction to what the guidebook covers and how it keeps itself honest — not a machine translation of it.

The one rule: every claim carries a label

This field mixes established physics with informed speculation, and most popular treatments blur the line — which is the same as lying. So the guidebook labels every claim with one of four levels of confidence:

  • 確立 · ESTABLISHEDRepeatedly confirmed by observation and experiment. Textbook material.
  • 有力な仮説 · LEADING HYPOTHESISWidely supported by researchers with indirect evidence — but unsettled.
  • 検証困難 · HARD TO TESTThe theory works on paper, but current technology cannot check it in practice — sometimes in principle.
  • 解釈 · INTERPRETATIONExperiment can never decide it. A question of how to read the same mathematics.

The labels do real work. By the final chapter, "what do we actually know?" has a precise answer instead of a shrug.

The twelve chapters

  1. How much of the universe can we see? — the observable universe, and why its radius is 46.5 billion light-years in a 13.8-billion-year-old cosmos. Established.
  2. Levels 1 and 2: beyond the horizon, and the bubble universes — eternal inflation's consequence for a flat, infinite space.
  3. Try it: one particle, two slits — an interactive double-slit experiment you operate yourself.
  4. Level 3: many-worlds as "subtraction" — Everett's reading, presented as the option that removes the collapse postulate rather than adding worlds by hand.
  5. The branching you — lunch choices, survival probabilities, and what "probability" can still mean if every branch happens.
  6. String theory: why extra dimensions are needed — and what the demand costs.
  7. The landscape: a universe with a settings file — the string landscape's ~10⁵⁰⁰ vacua and why it tempted physicists toward anthropic reasoning.
  8. Summary: the four levels of the multiverse — Tegmark's hierarchy, sorted with the honesty labels.
  9. What the latest observations say (2025–2026) — CMB anomalies and what would, or wouldn't, count as evidence of a collision with another bubble.
  10. Is there free will, or is everything determined? — where many-worlds genuinely touches philosophy.
  11. The infinite computer — computation without purpose or direction at the bottom of it all.
  12. So what is consciousness for? — the closing chapter, kept carefully inside the interpretation label.

Who writes it, and how to read it

The guidebook is part of toriumis.com, a one-person studio's collection of free learning sites and tools — a quantum mechanics course for non-scientists lives on the same domain, and the two are designed to be read together.

The working language of the guidebook is Japanese. If you read Japanese even slowly, the interactive experiments need no language at all — start with Chapter 1 and see whether the format works for you. If demand from English readers ever justifies it, a full English edition is the natural next step; this page exists so that at least the shape of the thing is visible now.

A note on honesty. Nothing on the guidebook's pages claims the multiverse is real. What the labels allow you to see, chapter by chapter, is exactly where observation ends and where interpretation begins — which is a rarer thing to find than another confident summary.