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arXiv · 1609.09686

Strong factorization property of Macdonald polynomials and higher-order Macdonald's positivity conjecture

Maciej Dołęga
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Abstract

We prove a strong factorization property of interpolation Macdonald polynomials when $q$ tends to $1$. As a consequence, we show that Macdonald polynomials have a strong factorization property when $q$ tends to $1$, which was posed as an open question in our previous paper with F\'eray. Furthermore, we introduce multivariate $q,t$-Kostka numbers and we show that they are polynomials in $q,t$ with integer coefficients by using the strong factorization property of Macdonald polynomials. We conjecture that multivariate $q,t$-Kostka numbers are in fact polynomials in $q,t$ with nonnegative integer coefficients, which generalizes the celebrated Macdonald's positivity conjecture.

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Maciej Dołęga. 2016-09-30. Strong factorization property of Macdonald polynomials and higher-order Macdonald's positivity conjecture. https://doi.org/10.1007/s10801-017-0750-x

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