Within Einstein's general theory of relativity, gravitation is described geometrically in the form of a four-dimensional curved spacetime which is formulated by the mathematical theory of differential geometry. Light rays are deflected by gravitational sources because of the curvature of spacetime. The bending of light rays can be taken into account by non-linear ray tracing. In this way, images as seen by an observer - a camera - under the influence of a gravitational field can be generated.
General relativistic ray tracing can be the basis for various visualization techniques in gravitational physics. First, ray tracing provides an intuitive approach to numerical or analytical results of gravitational physics, which is especially useful for presentations to colleagues or a wider public. Secondly, it allows a systematic investigation of light rays and the underlying geometry of spacetime. Thirdly, fractal structures for light rays can be identified. Fourthly, the properties of a gravitational lens can be explored, especially its caustic structure.
Check out the results of the visualization of the rigidly rotating disk of dust.
Contact: Daniel Weiskopf
[1] D. Weiskopf, M. Ansorg: Visualization of the General Relativistic Rigidly Rotating Disk of Dust, Annalen der Physik, 9 (2000) Spec. Issue, 179-18
[2] D. Weiskopf: Four-Dimensional Non-Linear Ray Tracing as a Visualization Tool for Gravitational Physics, IEEE Visualization 2000 Proceedings, T. Ertl, B. Hamann, A. Varshney (eds.), ACM Press, October 2000, 445-448.