Rotation in 2D by an angle $t$ can be performed using $$R=\begin{pmatrix}\cos(t) &-\sin(t) \\ \sin(t) & \cos(t)\end{pmatrix}$$ matrix. But, if I want to rotate a point or vector in 4D, is there any rotation matrix in explicit form? I have read rotation about planes in 4D (Rotating two planes while the other two planes remains constant), but I am interested in rotation around an axis. More specifically the Quaternion 4D rotation matrix. Kindly help me out. Login To add answer/comment