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Reducibility of polynomials $f(x,y)$ modulo $p$

Wolfgang M. Ruppert
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Abstract

We consider absolutely irreducible polynomials $f \in Z[x,y]$ with $°_x(f)=m$, $°_y(f)=n$ and height $H$. We show that for any prime $p$ with $p>c_{mn} H^{2mn+n-1}$ the reduction $f \bmod p$ is also absolutely irreducible. Furthermore if the Bouniakowsky conjecture is true we show that there are infinitely many absolutely irreducible polynomials $f \in Z[x,y]$ which are reducible mod $p$ where $p$ is a prime with $p>H^{2m}$.

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Wolfgang M. Ruppert. 1998-08-05. Reducibility of polynomials $f(x,y)$ modulo $p$. https://arxiv.org/abs/math/9808021

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