A carom billiard to understand special relativity

Abstract

Relativity, as introduced by Einstein, is regarded as one of the most important revolutions in the history of physics. Nevertheless, the observation of direct outcomes of this theory on mundane objects is impossible because they can only be witnessed when travelling at relative speeds approaching the velocity of light c. These effects are so counterintuitive and contradicting with our daily understanding of space and time that physics students find it hard to learn relativity beyond mathematical equations and to understand the deep implications of the theory. Advances in Computer Graphics and Interaction Technology now make it possible to actually experiment the effects of relativity in a 3D immersive environment. We propose a Virtual Reality framework to study and learn relativity as well as to develop some intuition of the relativistic effects and the quadri-dimensional reality of space-time. More precisely, an innovative rendering engine and a non-Newtonian physics engine are combined to compute relativistic effects. Experiments are proposed within a game-oriented carom billiard environment. Our work improves over previous efforts in the ability i) to render in real-time multiple relativistic objects, each moving with a different velocity vector ii) to enable interactions between objects and iii) to enable the user to interact with the objects and modify the scene dynamically. The originality of our 4D rendering engine lies in its capacity to efficiently store and retrieve non-simultaneous past space-time events that are visible by an observer at a specific location and at a given instant of his proper time.