Nikolai Lobachevsky

Nikolai Lobachevsky was a Russian mathematician known for his work in non-Euclidean geometry. Unlike Euclidean geometry, which follows the rules of parallel lines never meeting, Lobachevsky explored the concept that parallel lines could indeed meet, leading to a whole new branch of mathematics.

For school students, understanding non-Euclidean geometry can be explained through examples such as the surface of a sphere. On a sphere, lines of longitude are meridians that meet at the poles, unlike parallel lines on a flat surface. Lobachevsky's work challenged the traditional notions of geometry taught in schools and expanded our understanding of mathematical possibilities."