ELI5: Explain Like I'm 5

Rotation operator (vector space)

A rotation operator is like moving a toy ball around in a circle. Imagine you have a toy ball that you can spin around using your hand. When you spin the ball around, it moves and changes its position. The ball is like a point in space, and when you spin it, you are performing a rotation operation.

Similarly, a rotation operator in vector space is like spinning an arrow or a vector around a fixed point. A vector is a little arrow that has a direction and a length. When you apply a rotation operator to a vector, it changes its direction and position but keeps its length the same.

To understand it better, imagine you have a vector pointing in a particular direction. Now, you want to rotate the vector 90 degrees counter-clockwise. To do this, you would apply a rotation operator, which is a matrix that performs the necessary transformations to achieve the desired rotation.

Once applied, the rotation operator will transform the original vector into a new vector that is 90 degrees counter-clockwise to its original position. This new vector will have the same length as the old one but a different direction.

Think of the rotation operator as a tool that helps you move a vector around without changing its length. It's like moving a toy ball using your hand but in a more precise and calculated way.

In summary, rotation operators are tools that help you rotate vectors around a point without changing their length. They are like magic tricks that allow you to move things in space in a controlled and precise manner.