FACTOID # 23: In Australia, there's plenty of open road. Which is just as well, because you wouldn't want to park your car.
 
 Home   Encyclopedia   Statistics   Countries A-Z   Flags   Maps   Education   Forum   FAQ   About 
 
WHAT'S NEW
RECENT ARTICLES
More Recent Articles »
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Function field

In algebraic geometry, the function field of an irreducible algebraic variety is the field of fractions of the ring of regular functions.


The ring of regular functions on a variety V defined over a field K is an integral domain if and only if the variety is irreducible, and in this case the field of fractions is defined. It is a field extension of the ground field K; its transcendence degree is by definition the dimension of the variety. All extensions of K that are finitely-generated as fields arise in this way from some algebraic variety.


In the particular case of an algebraic curve C, that is, dimension 1, it follows that any two non-constant functions F and G on C satisfy a polynomial equation P(F,G) = 0.


Properties of the variety V that depend only on the function field are studied in birational geometry.


  Results from FactBites:
 
Function Fields (1849 words)
The function field of the curve is the corresponding field of fractions.
This is a vector subspace of the function field of a curve.
Since function fields are realised by completely separate code, one cannot automatically expect rational functions written in terms of the generators of the coordinate ring of the curve to be elements of the function field.
Function Fields (2592 words)
The function field of the curve is the corresponding field of fractions in the affine case and the homogeneous degree 0 part of this in projective cases.
As with schemes generally, a function field is attached to projective curves and the same object represents the function field of all of its affine patchs.
Return the function f in the function field of a scheme as a function in projective coordinates (as an element in the field of fractions of the coordinate ring of the projective scheme having function field the parent of f).
  More results at FactBites »


 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments
Please enter the 5-letter protection code

Want to know more?
Search encyclopedia, statistics and forums:

 


Lesson Plans | Student Area | Student FAQ | Reviews | Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms.