Mechanical Pendulums vs Relativity Simulator

In mechanics, in the area of dynamical system, a N-tuple pendulum is a set of N simple pendulums attached to each other. These N-tuple pendulums are physical systems that exibits rich dynamical behavior. For certain energies, are the motion of these mechanical pendulums often chaotic. You can influence the motion of the pendulums by holding your device in different positions. The equations of motions of these pendulums has been derived using the Sophia mechanical package. The different set of differential equations are solved using the 4:th order Runge-Kutta method for the time stepping. Within this application you can switch between these mechanical pendulums: - Double - Triple - Quadruple - Quintuple - Sextuple - Octuple - Symmtric Double - Simple 3-Dimensional The visualization of the pendulums can be viewed in either a Quartz view or in an OpenGL view.

Relativity Simulator is an interactive relativity toolkit built strictly on the axiomatic foundations of modern physics. There is no "hard sci-fi" here — every result traces back to the Lorentz transformation of special relativity or the Einstein field equations of general relativity, and is verified against numerical truth fixtures. 【Real physics, not imagination】 · 20 interactive modules covering core effects from special relativity to black holes, gravitational waves, and curved spacetime; · Each module ships with precise charts, adjustable parameters, and a "Theory Card" with a fully visible derivation chain; · All demo numbers are recomputed locally on your device from real CODATA constants — nothing is fabricated. 【Phenomena you can verify yourself】 · Gravitational time dilation: why clocks run faster up high — ~80 ns/day faster atop Everest, ~38 µs/day faster on GPS satellites; · Twin paradox: fly to 4.22 light-years at 0.8c and the Earth twin ages 10.5 years while the traveler ages only 6.3; · Tidal disruption: why you get stretched into "spaghetti" falling into a black hole — small holes tear you outside the horizon, supermassive ones only after you cross it; · Plus light bending, gravitational lensing, the Schwarzschild horizon, frame dragging, and mass–energy equivalence E=mc². 【Built for learning and teaching】 · Volume-based progression: kinematics → gravitational field → black holes → cosmology → applications; · Bilingual (zh/en) system notes ship with every effect: derivation, physical quantities, and references; · Chinese / English UI follows your system language. 【Privacy first】 The app collects, stores, and transmits no personal data, embeds no third-party SDKs, and runs every computation locally on your device. Whether you are studying, teaching, or simply curious, Relativity Simulator lets you actually run the "invisible spacetime" and watch it.