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:
“Had I made capital on my prettiness, I should have closed the doors of public employment to women for many a year, by the very means which now makes them weak, underpaid competitors in the great workshop of the world.”
—Jane Grey Swisshelm (18151884)
“In the quilts I had found good objectshospitable, warm, with soft edges yet resistant, with boundaries yet suggesting a continuous safe expanse, a field that could be bundled, a bundle that could be unfurled, portable equipment, light, washable, long-lasting, colorful, versatile, functional and ornamental, private and universal, mine and thine.”
—Radka Donnell-Vogt, U.S. quiltmaker. As quoted in Lives and Works, by Lynn F. Miller and Sally S. Swenson (1981)