cuRRay stands for CUDA relativistic raytracer and is a software capable of creating images of black holes and objects in their vicinity. According to Einstein's general theory of relativity, light is deflected by gravity (see figure 1). This leads to images of objects near black holes being distorted or even appearing multiple times. Black holes exhibit an extreme gravitational filed an thus the light bending effect is very strong. By analysing the images created by cuRRay, one can get insight into the curvature of spacetime, which is the reason for gravity in Einstein's theory, outside of black holes.
The software cuRRay as well as some images created by it and the PDF of the project (german and english) can be found on my GitLab repository.