PPolySim OS
Physics & Quantum Pack · Multi-Solver

Relativity Lab

Dilation & Doppler. This multi-solver chains 2 solvers into a single guided workflow — run each step in order and carry the result forward.

Workflow steps
  1. special-relativity
  2. doppler
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1

Special Relativity

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Special RelativityLive

Controls

Presets

Near the speed of light, space and time warp. The Lorentz factor γ = 1/√(1−v²/c²) governs it all: moving clocks run slow by γ (time dilation), moving objects shrink along their motion by 1/γ (length contraction), and energy grows without bound. At everyday speeds γ ≈ 1, so we never notice.

▶ Run in Python

Data Inspector

Lorentz factor γ1.250
Time dilation×1.25
Length contraction×0.800
Speed180 Mm/s

Governing equation

Reading this result: Deep in the relativistic regime — moving clocks run visibly slow and rulers shrink markedly along the motion.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

Doppler EffectLive

Controls

A moving source squeezes its wavefronts ahead and stretches them behind — higher pitch approaching, lower pitch receding. Push past the wave speed for a sonic boom.

Presets

▶ Run in Python

Data Inspector

Mach number0.68
Regimesubsonic
Source freq440 Hz
Approaching f'1383 Hz
Receding f'262 Hz

Governing equation

Reading this result: Approaching, the 440 Hz source is heard higher — about 1383 Hz; receding, it drops to about 262 Hz. The faster the source (Mach 0.68), the wider that split.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Frequently asked questions

What is the Relativity Lab multi-solver?
Relativity Lab is a guided workflow that chains 2 individual PolySim solvers into one end-to-end analysis, piping each result into the next step.
Is it free to use?
Yes. Every step runs entirely in your browser using real numerics — no install, no account, no cloud cost. Custom or private solver packs are available as a paid service.