Bloch Sphere

$\rho =\frac{1}{2}(I+\overrightarrow{r}\cdot \overrightarrow{\sigma })$, used to representation a Qubit, where:

• $\rho$ is any Density Operator
• $\overrightarrow{r}\in {\mathbb{C}}^3$ -$\rho =\frac{1}{2}(I+\overrightarrow{r}\cdot \sigma )$, used to representation a Qubit, where:
• $\rho$ is any Density Operator
• $\overrightarrow{r}\in {\mathbb{C}}^3$
• $\sigma =[{\sigma }_x,{\sigma }_y,{\sigma }_z]$ are the Pauli Matrixes.