- #1

rocdoc

Gold Member

- 43

- 3

In cartesian coordinates the unit dyadic$$\underline{\underline{I}}$$is given by

$$\underline{\underline{I}}=\mathbf{i}\mathbf{i}+\mathbf{j}\mathbf{j}+\mathbf{k}\mathbf{k}$$

The unit dyadic has the property that the two dot products between it and a vector, act so as to multiply the vector by a unit scalar,as below$$\underline{\underline{I}}\cdot\mathbf{v}=\mathbf{v}\cdot\underline{\underline{I}}= 1\mathbf{v}= \mathbf{v}$$