Quiver representation morphism
= Quiver representation morphism
{title2=$h_{t(\rho)}f_\rho=g_\rho h_{s(\rho)}$}
For <quiver representations> $X=(X_i,f_\rho)$ and $Y=(Y_i,g_\rho)$, a morphism consists of maps $h_i:X_i\to Y_i$ satisfying $h_{t(\rho)}f_\rho=g_\rho h_{s(\rho)}$ for every arrow. Composition is vertexwise. These families are the kernel of the <extension complex of quiver representations>.