(printable view)

Roots appear in quanta

American Mathematical Monthly Cover Alexander R. Perlis.
Roots appear in quanta.
American Mathematical Monthly 111 (2004), 61-63.

When you construct a field extension by adjoining one root of an irreducible polynomial, how many roots of that polynomial appear in the constructed field? That number is called the root quantum number. It places restrictions on how many roots appear in arbitrary field extensions, and it places restrictions on how a polynomial can factor over a field extension. Connections with Galois theory are given, and exercises at the end give a complete classification of the possible root quantum numbers for polynomials with rational coefficients.

2000 Mathematics Subject Classification (MSC):
  • 12F05 Field theory and polynomials | Field extensions | Algebraic extensions
  • 12F10 Field theory and polynomials | Field extensions | Separable extensions, Galois theory
  • 12F12 Field theory and polynomials | Field extensions | Inverse Galois theory
Key words and phrases:
  • irreducible polynomial
  • root quantum number
  • stem field
  • counting roots
  • number of roots

Downloads:

Image of page 1 Roots appear in quanta.
Last change: 08 October 2003.
DVI11K
PDF82K
PS68K

My agreement with the MAA gives me permission to post the article here. For the curious: the Monthly's version (PDF) of the article (the text is identical).
Image of page 1 Roots appear in quanta: exercise solutions.
Last change: 08 October 2003.
DVI20K
PDF142K
PS126K

If you discover alternate solutions, especially shorter or more elementary ones, please let me know.

Related work: