Quasi-algebraically Closed Field

Quasi-algebraically Closed Field

In mathematics, a field F is called quasi-algebraically closed (or C1) if every non-constant homogeneous polynomial P over F has a non-trivial zero provided the number of its variables is more than its degree. The idea of quasi-algebraically closed fields was investigated by C. C. Tsen, a student of Emmy Noether in a 1936 paper; and later in the 1951 Princeton University dissertation of Serge Lang. The idea itself is attributed to Lang's advisor Emil Artin.

Formally, if P is a non-constant homogeneous polynomial in variables

X1, ..., XN,

and of degree d satisfying

d < N

then it has a non-trivial zero over F; that is, for some xi in F, not all 0, we have

P(x1, ..., xN) = 0.

In geometric language, the hypersurface defined by P, in projective space of dimension N − 1, then has a point over F.

Read more about Quasi-algebraically Closed Field:  Examples, Properties, Ck Fields

Famous quotes containing the words closed and/or field:

    One man’s observation is another man’s closed book or flight of fancy.
    Willard Van Orman Quine (b. 1908)

    When it had long since outgrown his purely medical implications and become a world movement which penetrated into every field of science and every domain of the intellect: literature, the history of art, religion and prehistory; mythology, folklore, pedagogy, and what not.
    Thomas Mann (1875–1955)