Gravity Inverted
R² 1.000000
Gravity points up: g = +9.81 m/s² (inverted). The ball falls to the ceiling and rests there.
Fitted vs set: a_fit = +9.8100 vs +9.81 (0.0% err)
InfiniteWorld — Parallel-Physics Worlds
Videos from worlds where the laws are different — with exact ground truth.
Gravity Scaled
R² 1.000000
Gravity at 15%: g = −1.4715 m/s². Slow-motion drop with low, floaty bounces.
Fitted vs set: g_scale_fit = 0.1500 vs 0.15 (0.0% err)
Friction Zero
R² 1.000000
Friction removed: μ = 0. The pushed box slides forever; at reference μ = 0.4 it would stop in 0.154 m.
Fitted vs set: v_fit = 1.100000 m/s vs 1.10 (velocity variation 0.0)
Restitution Super
R² 0.999930
Super-elastic bounces: e = 1.25, each apex × e² = 1.5625 (speed clamp 8 m/s).
Fitted vs set: e_fit = 1.248555 vs 1.25 (0.11% err)
Dissipation Air
R² 1.000000
Thick air: in-flight velocity decays at k = 1.2/s (continuous rate 1.2030/s). The arc dies mid-air.
Fitted vs set: k_fit = 1.20301 vs 1.2030 (0.25% err)
Buoyancy Inverted
R² 1.000000
Inverted buoyancy: submerged dense stone feels F = 1.8·m·g upward — it bobs and floats at the waterline.
Fitted vs set: pre-entry g_fit = −9.8100; settle residual 0.0095 m < r = 0.12 m