Motion-as-metric: 2D Interactive Simulator

adrijanjosic.com

Special Relativity kinematics in absolute space.

This 2D simulator implements the null loop rules—fixed carrier speed and work-free bending as defined in Motion-as-Metric: Relativity and Gravity Without Curvature

Users can fly around and visualize null constituents fixed speed trails as they circulate around the loop. Watch contraction, dilation, and do radar ranging directly at speeds up to 0.95c

3 different views are supported, absolute fixed, absolute follow and self-relative mode.
The self-relative mode compensates for time dilation (we do this by changing c_abs as if it were the update step) and contraction (pure canvas strech after draw). Due to this compensation, two way measurement in self-relative mode takes equal time in user seconds at any speed.

Fly around with arrow keys, take two-way radar measurement with space. HUD display on the left keeps last 10 measurements. Ideal measurement is 2π.

Play with parameters on the right hand side.
Lower number of constituents and bigger radius cause imprecision due to low circulation rate (which is what we measure time by in the loop frame - operational). Longer radar rods naturally aid precision. Gravity is WIP and limited to 0.65c.

Press Space or click Start to close this window and begin the simulation.

This software is intended as complementary proof-of-concept demonstration and a pedagogical aid

Motion-as-Metric: 2D Interactive Simulator

speed 0.00c

0.5c

Use arrow keys to move. Space for radar ping. For better ping accuracy use more constituents, smaller radius and longer radar rod.

Parameters

absolute c (px/s) 260

effective c (px/s) 260

R0 (rest semi-axis) [px] 80

Gravity factor[WIP] (×c) 0.00

g absolute (px/s²) 0

Constituents

# of constituents 16

Zoom (x) 1.00

Trail length (s) 3.20

Radar rod L (px, loop rods) 260

Views & Controls

Arrows to accelerate (|V| ≤ 0.95·c; 0.65·c when g>0).

Space = Ping radar. C = Chirality . P = Pause.

View mode

Abs. Fixed Abs. Follow Self‑relative

Faded trails (axis-phased)

Night mode

Auto-pause on measurement

MIT License

MIT License

Copyright (c) 2025 Adrijan Josić 

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