English

Some new canonical forms for polynomials

Algebraic Geometry 2016-01-20 v2 Number Theory

Abstract

We give some new canonical representations for forms over \cc\cc. For example, a general binary quartic form can be written as the square of a quadratic form plus the fourth power of a linear form. A general cubic form in (x1,...,xn)(x_1,...,x_n) can be written uniquely as a sum of the cubes of linear forms ij(xi,...,xj)\ell_{ij}(x_i,...,x_j), 1ijn1 \le i \le j \le n. A general ternary quartic form is the sum of the square of a quadratic form and three fourth powers of linear forms. The methods are classical and elementary.

Keywords

Cite

@article{arxiv.1203.5722,
  title  = {Some new canonical forms for polynomials},
  author = {Bruce Reznick},
  journal= {arXiv preprint arXiv:1203.5722},
  year   = {2016}
}

Comments

I have spoken about this material under the title "steampunk canonical forms". This is the final revised version which has been accepted by the Pacific Journal of Mathematics. Apart from the usual improvements which come after a thoughtful refereeing, Theorem 1.8 is new

R2 v1 2026-06-21T20:40:00.626Z