(1)
There are sixteen equations describing 14 field quantities.
To cast these in quaternion form it’s easiest to write the
quaternions in vector-scalar format. Write the quaternion
as
(2)
where q is
the three-vector
in ordinary three
dimensional space. ex ey ez are
Cartesian unit vectors.
Multiplication of two quaternions A and B is
(3)
Define a quaternion gradient operator:
(4)
(5)
(6)
So, in summary, define quaternions M and N and S as:
(7)
Then the Maxwell equations of (1) are equivalent to the
quaternion equations:
(8)