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Associated forms in classical invariant theory and their applications to hypersurface singularities

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Abstract

It was conjectured in the recent article by Eastwood and Isaev that all absolute classical invariants of forms of degree \(m\ge 3\) on \({\mathbb C}^n\) can be extracted, in a canonical way, from those of forms of degree \(n(m-2)\) by means of assigning every form with non-vanishing discriminant the so-called associated form. This surprising conjecture was confirmed for binary forms of degree \(m \le 6\) and ternary cubics. In the present paper, we settle the conjecture in full generality. In addition, we propose a stronger version of this statement and obtain evidence supporting it.

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Acknowledgments

This work is supported by the Australian Research Council.

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Correspondence to Alexander Isaev.

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Alper, J., Isaev, A. Associated forms in classical invariant theory and their applications to hypersurface singularities. Math. Ann. 360, 799–823 (2014). https://doi.org/10.1007/s00208-014-1054-2

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