2012-2016: Gerd Kortemeyer, Philip Tan, Zach Sherin, Ryan Cheu, Steven Schirra & Sonny Sidhu

OpenRelativity is an open-source toolkit to simulate effects of special relativity by varying the speed of light. Developed by the MIT Game Lab, it contains open-source code for public use with the free and paid versions of the Unity engine. The toolkit was developed during the creation of the game A Slower Speed of Light.

Research Question

An intuitive understanding of travel near the speed of light can be difficult to develop. The concepts involved in special relativity seem remote and inaccessible to us in our daily lives. Students and teachers of special relativity have very little in the way of tangible demonstrations, and are typically expected to develop understanding solely through the reading and working of theoretical problems.

Intended for game developers, educators, and anyone interested in physics, OpenRelativity can help people create, test, and share experiments to explore the effects of special relativity. By releasing the tool set as an open-source code library, interested developers can also create and distribute new games or simulations that feature the effects of traveling near the speed of light.

Education can be assisted through the use of games and other interactive media, especially for topics that frequently are hard to understand and visualize. The toolset can help educators create new demonstrations to provide an intuitive, useful understanding of a dense and complex topic. At the same time, these tools make the visually stunning effects of traveling near the speed of light available to game developers, increasing awareness about the topic to people who may have never encountered it. Our hope is that software created with OpenRelativity will allow a greater number of people access to a field that is often regarded as difficult to comprehend.

    • OpenRelativity involves the real-time computation of vertex and fragment geometry to simulate the following effects:
  • 3D Lorentz transformation of stationary or constant-velocity geometry
  • Time dilation of moving objects
  • Relativistic doppler shift of objects moving relative to the camera
  • Searchlight/headlight effect as perceived by a moving camera
  • Runtime of light effects when events are perceived by the camera


Technical Support and Bug Reports

Please direct bug reports, technical questions, and problems to


Zachary W. Sherin, Ryan Cheu, Philip Tan, and Gerd Kortemeyer, (2016): Visualizing Relativity: the OpenRelativity Project, American Journal of Physics 84, 369-374


See OpenRelativity in action in the following games (contact if you make a project with this toolkit and want it added to our list):

2012, MIT Game Lab

A Slower Speed of Light is a first-person game in which players navigate a 3D space while picking up orbs that reduce the speed of light in increments. Visual effects of special relativity gradually become apparent to the player, increasing the challenge of gameplay. Players can choose to share their mastery and experience of the game through Twitter. A Slower Speed of Light combines accessible gameplay and a fantasy setting with theoretical and computational physics research to deliver an engaging and pedagogically rich experience.


2016, MIT Game Lab & Museum of Science, Boston

“Einstein’s Playground” is a new show designed specifically for a live, narrated presentation, using the flexibility of interactivity to adjust to the needs for a large audience. Produced with the Museum of Science Boston, this presentation was given on February 11, 2016. Live visuals from our OpenRelativity game engine were projected onto the dome of the Charles Hayden Planetarium to demonstrate the theory of Special Relativity. This show combines the Master’s thesis work of Zachary Sherin ’15 with the teaching skills of Dr. Gerd Kortemeyer from Michigan State University, both of whom worked on “A Slower Speed of Light” in 2012.