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Кыргызча🌊 Gravitational Wave Chirp — LIGO Inspiral Waveform Interactive
Interactive gravitational wave chirp simulator. Set binary masses and distance, watch the h(t) strain waveform sweep from low to high frequency as two compact objects spiral together and merge. Includes spectrogram and LIGO detector noise overlay.
About this simulation
This simulation traces the chirp of a compact-binary inspiral: two black holes spiralling together as gravitational waves carry away orbital energy. The chirp mass, M_c = (m₁m₂)^(3/5)/(m₁+m₂)^(1/5), sets how fast the separation shrinks, while Kepler's third law gives the orbital frequency. Frequency and strain climb toward a peak at the innermost stable circular orbit (ISCO), then the remnant rings down — all recalculated live, not a canned animation.
🔬 What it shows
Separation between the two bodies shrinks under the quadrupole radiation formula. A dashed ring marks the ISCO (three Schwarzschild radii), where inspiral gives way to a merger flash and decaying ringdown. The h(t) strain plot builds up live, coloured by amplitude, with a phase label tracking Inspiral, Merger and Ringdown.
🎮 How to use
Set the masses with the m₁ and m₂ sliders (1–80 M☉, default 30/25) and distance with the Distance slider (10–5000 Mpc, default 400). Eccentricity (0–0.7) is reserved for a future orbit model — the build always runs a circular inspiral. Speed (1–200×) scales playback; Restart and Pause reset or freeze it.
💡 Did you know?
GW150914, the event this simulator echoes, merged two black holes of about 36 and 29 solar masses on 14 September 2015, radiating roughly 3 solar masses as gravitational waves in under a second — briefly the most powerful gravitational-wave source in the observable universe.
Frequently asked questions
How does the chirp mass drive the waveform?
It sets the rate constant β = (64/5)G³m₁m₂(m₁+m₂)/c⁵ in r(t)⁴ = 4β(t_merger − t) — the single combination controlling the whole frequency sweep, which is why it's the best-measured parameter from a real signal.
Why doesn't Eccentricity change the orbit's shape?
The model always evolves a circular inspiral, so the slider is a placeholder for a future update rather than an active parameter. Real binaries circularise quickly anyway, so this is realistic for the late inspiral shown here.
What sets the frequency and strain at merger?
Merger is defined at the ISCO, three Schwarzschild radii of the total mass. Merger frequency comes from Kepler's law there, and peak strain uses the same amplitude formula, h ∝ (GM_c/c²)^(5/3)(πf)^(2/3)/distance.
How is the ringdown modelled?
After the ISCO, the animation switches to a damped sinusoid for the remnant's dominant quasinormal mode: an exponentially decaying strain with a roughly 20 ms damping time, loosely matched to GW150914's own ringdown.
Why does distance shrink the waveform but not its frequency sweep?
Strain falls off as 1/distance since the wave's energy spreads over an ever-larger sphere. Frequency evolution depends only on the masses, so a distant source sounds quieter without chirping any slower or faster.
Set binary masses and distance, watch h(t) strain waveform sweep and chirp, spectrogram, LIGO noise overlay. Inspiral, merger and ringdown phases.
3D · Three.js / WebGL renderer · 60 FPS target · runs fully client-side, no install