deletions | additions       diff --git a/Introduction.tex b/Introduction.tex  index a04f816..46ae586 100644  --- a/Introduction.tex  +++ b/Introduction.tex 
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k & 0 & 0 & -1  \end{bmatrix}  \begin{bmatrix} dt \\ dx \\ dy \\ dz \end{bmatrix}  \end{equation} This would be equaivalent to a new type of number with the rules \begin{equation}  i \cdot i =-1 \\  j \cdot j =-1 \\  k \cdot k =-1 \\  ij=ji=0 \\  ik=ki=0 \\  jk=kj=0  \end{equation}  This is similar to having 3 independant imaginary numbers.