Tabletop gravitational waves waveform simulator

Abstract We present a simple and intuitive tabletop experiment designed to generate gravitational wave-like signals. This toy model serves as a physical analogy for the motion of compact astrophysical objects in curved spacetime and is intended primarily for educational and outreach purposes. The experimental setup consists of a circular solid frame over which an elastic fabric is tightly stretched and secured with clips. Solid spheres of different masses represent astrophysical objects, and their motion is recorded using a webcam connected to a laptop running the TableTopGW software. A heavy sphere is placed at the center of the fabric to simulate a massive compact object, such as a black hole or neutron star, that distorts the surrounding spacetime. A lighter sphere is then released onto the curved surface, where it spirals inward toward the central mass under the influence of Earth’s gravity and friction with the fabric. The webcam continuously records the motion of both spheres. From this video data, the separation between the two masses is computed. Using the quadrupole formalism from general relativity, as applied to binary systems, the TableTopGW software uses this separation to simulate gravitational wave-like signals. This setup establishes a direct and visually engaging connection between the physical motion of orbiting bodies and the corresponding gravitational waveform, offering students and the general public an accessible and hands-on introduction to complex astrophysical concepts.