RealityModels: physics simulations

Visual simulations of theories and interpretations of reality: quantum mechanics, time, energy. The common thread is a mathematical block universe with many worlds, close to Max Tegmark's mathematical universe hypothesis: all of spacetime exists at once, motion is geometry and quantum branches are parts of the same structure.

Each simulation is a self-contained offline HTML page: open its index.html in a browser, a double click is enough. No server, no installation.

To hand out a simulation as one file, build the single-file versions:

node tools/build-standalone.js

It writes <simulation>.standalone.html next to each index.html, with all CSS and JavaScript (three.js included) embedded. That file runs anywhere on its own; only the links to the docs need the repository.

To publish the project on the web, upload it to any host with PHP 7.4 or later and open index.php. It lists the simulations and documents it finds on disk, so new ones appear without editing it, and shows each Markdown document as a page. URLs: index.php?sim=<subject>/<name>, index.php?doc=<subject>/<name>, &lang=it|en.

Italian version: README.it.md.

Simulations

Relativity

A moving body and a body at rest in the block universe, 2+1 spacetime. Guide: block-universe-simulations-guide.en.md. Theory: block-universe-relativity-theory.en.md.

Simulation	Content
length-contraction	Length contraction as the section of a tilted world tube.
time-dilation	Adds clock ticks and readings: time dilation.
accelerated-motion	A Born-rigid body that accelerates, brakes and stops: curved world tube.

Quantum mechanics

Guides: many-worlds-simulation-guide.en.md, many-interacting-worlds-simulation-guide.en.md. Theory: many-worlds-convergence-theory.en.md, many-interacting-worlds-theory.en.md.

Simulation	Content
many-worlds	Many worlds: a tree of branches versus branches that merge when they share the same record (classical lattice and quantum walk with interference).
many-interacting-worlds	Many interacting worlds: N classical worlds that repel each other reproduce uncertainty, zero-point energy, spreading, interference and collapse as selection of a sub-ensemble (Hall, Deckert and Wiseman, 2014).

Foundations

Glossary of the terms behind the project (MUH, CUH, it from bit, cumulative hierarchy, regress of containers): mathematical-universe-glossary.en.md.

Guide: algorithmic-probability-simulation-guide.en.md. Theory: algorithmic-probability-theory.en.md.

Simulation	Content
turing-census	Census of all the small Turing machines: the halting outputs build the universal distribution, simple strings win by counting alone.

Language and theme

The gear in the top-right corner opens the settings: language (Italian, English) and theme (system, light, dark). Choices are saved in the browser and shared by all simulations. ?lang=it or ?lang=en in the URL takes precedence.

Structure

README.md, README.it.md
docs/<subject>/
  <topic>-theory.{it,en}.md               theory, formulas, references
  <topic>-simulation(s)-guide.{it,en}.md  usage, parameters, numerical checks
  <topic>-glossary.{it,en}.md             terms, references
simulations/<subject>/<simulation>/
  index.html, css/, js/                   one simulation
simulations/shared/
  lib/                                    three.js r121 and OrbitControls (local copies)
  js/settings.js, css/settings.css        language and theme panel
tools/build-standalone.js                 builds the single-file versions
index.php                                 web front end: navigates simulations and docs

Subjects: relativity, quantum-mechanics, foundations.