DEFINITION 10.1
Let
be rings. Let
be a ring homomorphism.
We have already introduced
as a continuous map
. Now that the spaces
carry
structures of locally ringed spaces, we (re)define
as a morphism of locally ringed spaces by defining
as in Example
9.11.
PROOF..
Let us put
and
. The data
is equivalent to a data
which gives rise to a ring homomorphism
Let us take this homomorphism as
.
By the hypothesis of being a morphism of locally ringed spaces,
is local homomorphism.
That means,
From the definition of
, we have
We have thus proved that
is equal to as a map .