Twisted polynomial ring

In mathematics, a twisted polynomial is a polynomial over a field of characteristic ${\displaystyle p}$ in the variable ${\displaystyle \tau }$ representing the Frobenius map ${\displaystyle x\mapsto x^{p}}$. In contrast to normal polynomials, multiplication of these polynomials is not commutative, but satisfies the commutation rule

for all ${\displaystyle x}$ in the base field.

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