MARBLE RUN — credits, provenance and what is original here ========================================================== WHAT THIS IS ------------ An independent, from-scratch reimplementation of the physics a marble run poses: given a start and a finish, which track gets the marble down first? It is written in plain JavaScript, ships no library, loads nothing from any other host, calls no model, spends no credits and stores nothing off your machine. THE ORIGINAL ------------ A marble run (also marble track, marble maze, ball run) is a generic gravity-fed toy. It has no single inventor, no canonical publisher and no year of first publication that anyone can cite; English Wikipedia has no article for it (checked 2026-09-20). There is therefore no author to credit for the toy itself, and this project claims no connection to any commercial marble-run product, past or present. What CAN be credited, and is, are the people who answered the question the toy asks: Galileo Galilei, "Two New Sciences" (1638) — argued a circular arc beats any polygon of chords, and conjectured the quarter circle was quickest of all. It is not. He also named the cycloid and made the first serious study of it. https://en.wikipedia.org/wiki/Brachistochrone_curve https://en.wikipedia.org/wiki/Cycloid Christiaan Huygens (1659; published in "Horologium Oscillatorium", 1673) — proved that on this curve the time of descent to the lowest point is the same from every starting point. https://en.wikipedia.org/wiki/Tautochrone_curve Johann Bernoulli (1696) — posed the problem of the curve of quickest descent, and solved it by treating the body as a ray of light refracting through a medium that speeds up with depth. Published in Acta Eruditorum Lipsidae, May 1697. https://en.wikipedia.org/wiki/Brachistochrone_curve Isaac Newton (1697) — solved it in one night. Jakob Bernoulli, Leibniz and de l'Hopital also returned solutions. Charles de Bovelles, "Introductio in geometriam" (1503) — now credited with the first description of the cycloid. https://en.wikipedia.org/wiki/Cycloid WHAT IS INDEPENDENT HERE ------------------------ * The whole engine: a tanh-sinh quadrature for the descent integral, a coordinate-descent search over polylines, a layered refraction construction, and a Runge-Kutta integration of Newton's second law in the track parameter. Nothing was ported from any source. * The renderer, the interaction, the tables and the page. * Every number printed in the Workshop section is produced by this project's own test harness and re-checked by a second harness before release. None was typed in from a reference. * The closed-form descent time is used only to CHECK a search that was never given it. WHAT DIFFERS FROM A REAL MARBLE RUN ----------------------------------- * Frictionless, and the marble never leaves the groove. A real marble loses energy to rolling resistance and to the air, and a real marble can jump the track. * One plane, side on. No joints, no supports, no funnels, no noise. * You may choose what rolls: a sliding block, a solid marble, a hollow ball or a hoop. Only one of those is a marble. * Motion is shown at one third of real speed so it can be watched; the clock reads real seconds of simulated time, not wall-clock seconds. TRADE MARKS ----------- "MARBLE RUN" is a registered trade mark. A search of the TMview register (www.tmdn.org/tmview/) on 2026-09-20 returned the following marks on the name: MARBLE RUN EUIPO 019235434 Registered 2025-12-13 classes 9, 28, 41 proprietor: INTERBLOCK d.o.o. MARBLE RUN US 98624589 Registered 2026-04-14 classes 9, 28, 41 proprietor: Interblock d.o.o. MARBLE RUN CN 24205021 Registered 2018-05-14 class 28 MARBLE RUN IN 3088405 Registered 2015-10-28 class 28 MAGNETIC MARBLE RUN CN 53101009 Registered 2021-09-14 class 28 GALT MEGA MARBLE RUN EUIPO 011436268 / UK 00911436268 Registered 2013-05-20 class 28 MARBLE RUN US 87929253 Ended MR. MARBLE RUN US 87424025 Ended Marble Run Challenge UK 00003087474 Expired The two Interblock d.o.o. registrations (EUIPO 019235434 and US 98624589) cover Nice classes 9, 28 and 41, which include software and entertainment services. This page uses the words only as the ordinary English name of a gravity-fed toy track. It is free, carries no advertising and sells nothing. It is not affiliated with, endorsed by or connected to any proprietor listed above, Interblock d.o.o. included, and no product of theirs is reproduced or imitated here. No clearance opinion was sought and none is offered; this is a record of what the register says, not legal advice. LICENCE ------- This implementation is released under the MIT Licence; see LICENSE.txt. The historical facts above are facts. The Wikipedia text they are drawn from is CC BY-SA 4.0; no Wikipedia prose is reproduced here, only the facts it reports, restated.