Cosmology and astrophysics
Gravitational waves and multi-messenger astronomy
Observe a compact binary orbiting its barycenter emitting gravitational waves with fractional strain , and see why combining the gravitational signal with light or neutrinos makes multi-messenger astronomy. Vary the relative separation and view angle to compare ripple amplitudes.
Equipment
- Two compact objects orbiting the barycenter on a 3D canvas
- Slider for the relative separation of the two bodies
- View-angle slider and Pause button
- Gravitational-wave ripple rings with a simultaneous light signal
Procedure
Read wave amplitude versus separation
Drag the relative-separation slider from wide to close: the bodies orbit faster and the ripple rings deepen — gravitational-wave amplitude grows sharply as the orbit shrinks, following the time-varying quadrupole of Einstein's equation.
Estimate the strain h
The strain measures how much space is stretched relatively as the wave crosses a detector; in real events h ~ , so the simulation magnifies the rings. Pause and count ripples per orbital period — the wave frequency is twice the orbital frequency, .
Combine different messengers
Watch the light signal flash together with the gravitational ripples: the two 'messengers' carry complementary information — gravitational waves give masses and orbits, light gives composition and precise location. Change the view angle to see the wave plane spreading along the orbital plane.