In
algebraic geometry, a domain in
mathematics, a
morphism of
schemes
- f:X → Y
is called
radicial or
universally injective, if, for every
g:
Y' →
Y the
pullback of
f along
g is
injective.
This is equivalent to the following condition: for every point x in X, the extension of the residue fields
- k(f(x)) ⊂ k(x)
is radicial, i.e.
purely inseparable.
References
- , section I.3.5.
- , see section V.5.