So in the following lecture notes about epipolar geometry, the essential matrix and the fundamental matrix:
$T$ is the translation vector between the cameras. $P_l$ is the vector from $C_l$ to $P$. My question is, why is:
$$ P_r = R(P_l - T) $$
Here, $R$ is a rotation matrix. However, based on these vectors, I don't see why you need to rotate the vector. In fact, I think that the relationship should just be:
$$ P_r = P_l - T $$
Does anyone know why there is a rotation matrix?