This young German mathematician was preparing for his final presentation. To obtain a position in a German institution, a candidate had to give a public presentation of some new ideas and his performance would determine his acceptability. The applicant would submit three topics and the examiners would choose one of them. It was the unspoken, accepted practice of the day that the first item would be too simple, the second item would be the one chosen and the third one would be too difficult. Reimann's examiners included Karl Friedrich Gauss who was so intrigued by Reimanns third entry - having to do with curved spaces - that he asked Reimann to present that. Reimann was distressed for he was not sure he could do it. Nevertheless, he prepared a masterful presentation, greatly impressed even the great Gauss, was given the appointment, and worked closely with Guass for the duration of his career. Reimann is credited with laying the groundwork for the study of non-Euclidean, curved spaces. It turns out that the Euler-Lagrange equations correctly predict the motion of a particle even in these curved spaces and it also turns out to be the path of least action.
The development of these tools into physically important concepts for mechanics had to wait for the likes of Einstein, Minkowski, Schrödinger and others. In the meantime, Gauss and Reimann turned their attention to the emerging field of electrodynamics.