Mathematics – Number Theory
Scientific paper
2010-06-26
Mathematics
Number Theory
13 pages
Scientific paper
In this paper we will give a scheme-theoretic discussion on the unramified extensions of an arithmetic function field in several variables. The notion of unramified discussed here is parallel to that in algebraic number theory and for the case of classical varieties, coincides with that in Lang's theory of unramified class fields of a function field in several variables. It is twofold for us to introduce the notion of unramified. One is for the computation of the \'{e}tale fundamental group of an arithmetic scheme; the other is for an ideal-theoretic theory of unramified class fields over an arithmetic function field in several variables. Fortunately, in the paper we will also have operations on unramified extensions such as base changes, composites, subfields, transitivity, etc. It will be proved that a purely transcendental extension over the rational field has a trivial unramified extension. As an application, it will be seen that the affine scheme of a ring over the ring of integers in several variables has a trivial \'{e}tale fundamental group.
No associations
LandOfFree
On the unramified extension of an arithmetic function field in several variables does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with On the unramified extension of an arithmetic function field in several variables, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the unramified extension of an arithmetic function field in several variables will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-525733