A little universe. Entirely in your hands.
The Gravity Playground is an experiment from Up Against Reality, built with OpenAI’s Astra in Codex. Every point of light is a moving particle. The controls change its world.
Drag across the universe to pull particles toward you. Try two galaxies colliding, turn gravity inside out, or launch a supernova. Reset restarts your current experiment.
This is an artistic simulation with simplified forces, not a scientific model. It runs in your browser; it doesn’t send your interactions to an AI.
Keyboard: Tab to a slider and use the arrow keys. On the universe, use arrows to move the attractor and hold Enter to pull. Space pauses or resumes when the universe is focused. Reduced motion starts the experiment paused.
