Code: 1L20.10
Demo Title: Bending Spacetime
Subject: Orbits
Description: Demonstrates how mass curves spacetime to bend the paths of objects travelling near larger masses, such as light bending around a star.
Procedure:
Roll the yellow ball (representing Photon) across the flat surface of the spandex. It will travel in a straight line, simulating how light moves through empty space undisturbed.
Place a heavy ball (e.g., steel ball or cue ball) in the center of the fabric. This represents a massive object like a star or black hole. Observe how the fabric curves downward under its weight, visually simulating the curvature of spacetime.
Now roll the same “photon” ball past the curved region. You’ll see that instead of going straight, the ball curves around the dip caused by the heavy object—showing how light bends near massive bodies.
Gently roll a medium-weight ball around the heavy ball. If done right, it will spiral around the central mass, mimicking the orbit of a planet around a star. This models gravitational orbits due to spacetime curvature.
Try swapping the central object with heavier or lighter balls. Observe how the curvature changes and how it affects the light path and orbital motion.
Video URL: