Complex sentence: These come about from the fact that Wilson loops are based on matrices (the holonomy) and these matrices satisfy identities, the so-called Mandelstam identities.
Split into simpler sentences: These come about from the fact that Wilson loops are based on matrices (the holonomy) and these matrices satisfy identities. These idnetities are the so-called Mandelstam identities.the so-called Mandelstam identities.