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The tensor product notation $u \otimes v$ satisfies distributive laws and scalar mobility rules because it is constructed via a bilinear map $\varphi$. Bilinearity implies linearity in each variable separately, leading to $(a_1u_1+a_2u_2)\otimes v=a_1u_1\otimes v+a_2u_2\otimes v$, $u\otimes(b_1v_1+b_2v_2)=b_1u\otimes v_1+b_2u\otimes v_2$, and $a(u\otimes v)=(au)\otimes v=u\otimes(av)$.

Conditions: $u, u_1, u_2$ belong to $U$.; $v, v_1, v_2$ belong to $V$.; $a, a_1, a_2, b_1, b_2$ are scalars in the field $\mathbb{P}$.

The tensor product notation $u \otimes v$ satisfies distributive laws and scalar mobility rules because it is constructed via a bilinear map $\varphi$. Bilinearity implies linearity in each variable separately, leading to $(a_1u_1+a_2u_2)\otimes v=a_1u_1\otimes v+a_2u_2\otimes v$, $u\otimes(b_1v_1+b_2v_2)=b_1u\otimes v_1+b_2u\otimes v_2$, and $a(u\otimes v)=(au)\otimes v=u\otimes(av)$.

Conditions: $u, u_1, u_2$ belong to $U$.; $v, v_1, v_2$ belong to $V$.; $a, a_1, a_2, b_1, b_2$ are scalars in the field $\mathbb{P}$.