The notation SL(n, C) refers to the special linear group of degree n over the complex numbers. It consists of all n x n matrices with complex entries that have a determinant equal to 1. This group is important in various areas of mathematics, including algebra, geometry, and representation theory. SL(n, C) is a Lie group, meaning it has a smooth manifold structure and can be studied using calculus. It plays a crucial role in the theory of linear algebra and group theory, as well as in the study of symmetries in mathematics and physics.