2.1.1. Geometric Product

The crucial product operation in GA theory is the geometric product [30]. For vectors **a** and **b**, the geometric product is denoted by

$$\mathbf{a}\mathbf{b} = \mathbf{a} \cdot \mathbf{b} + \mathbf{a} \wedge \mathbf{b},\tag{1}$$

where {·} and {∧} denote the inner product and the outer product, respectively.
