Tag Archives: clifford algebra

Split-Complex Numbers as a Clifford Algebra


The split-complex numbers are a special case of Clifford Algebra. This can be seen as follows. Let X = \mathbb{R}^1. Let e_1 = \langle a \rangle with a \not  = 0 be a basis element of \mathbb{R}^1. Then the Clifford Algebra \mathcal{C}(\mathbb{R}^1) is defined as follows. The elements of the Clifford algebra are \alpha + \beta e_1. Setting the rule for the Clifford product e_1 \vee e_1 as

(1)   \begin{equation*}e_1 \vee e_1 = 1\end{equation*}


yields

    \[(\alpha_1 + \beta_1 e_1) \vee (\alpha_2 + \beta_2 e_1) = (\alpha_1 \alpha_2 + \beta_1 \beta_2) + (\alpha_1 \beta_2 + \beta_1 \alpha_2) e_1\]


The isomorphism is 1 \mapsto 1, e_1 \mapsto j. On the other hand, setting the rule to e_1 \vee e_1 = 0 or e_1 \vee e_1 = -1 in (1) yields a correspondence with dual-numbers or complex numbers respectively. I am planning to expand on this fact in one of the subsequent posts.