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arXiv · 2501.17504

Rational invariants of even degree polynomials under the orthogonal group

Henri Breloer
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Abstract

In this article, we construct a generating set of rational invariants for the action of the orthogonal group $\text{O}(n)$ on the space $\mathbb{R}[x_1,\dots,x_n]_{2d}$ of real homogeneous polynomials of even degree $2d$. This generalizes a paper which addressed the case $n=3$. The main difficult with the generalization lies in a surprising connection to the graph isomorphism problem, a classical problem of computer science.

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Henri Breloer. 2025-01-29. Rational invariants of even degree polynomials under the orthogonal group. https://arxiv.org/abs/2501.17504

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