CurrentModule = Oscar

General schemes

Arbitrary schemes over a commutative base ring \mathbb k with unit are instances of the abstract type

Scheme{BaseRingType<:Ring}

Morphisms of schemes shall be derived from the abstract type

SchemeMor{DomainType, CodomainType, MorphismType, BaseMorType}

Change of base

base_change(phi::Any, X::Scheme)
base_change(phi::Any, f::SchemeMor;
    domain_map::AbsSchemeMor, codomain_map::AbsSchemeMor
    )