PGL(n)

PGL(n), or projective general linear group, is a mathematical concept from abstract algebra. It considers all invertible linear transformations of an n-dimensional space, like rotations or scalings, but identifies any two transformations that differ only by a scale factor (multiplying by a non-zero number). Essentially, it captures how linear transformations act on directions (lines through the origin), ignoring size. This group helps mathematicians understand symmetries and geometric properties of spaces, playing a key role in areas like projective geometry and the study of symmetries in higher dimensions.