Diophantine frequency vector
= Diophantine frequency vector
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{title2=$|k\cdot\omega|\ge\gamma |k|_1^{-\tau}$}
= Diophantine condition
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{synonym}
A vector $\omega\in\mathbb R^n$ satisfying $|k\cdot\omega|\ge\gamma |k|_1^{-\tau}$ for all nonzero integer vectors $k$, with $\gamma>0$. This excludes resonances and controls the <small divisors> in analytic <cohomological equations on a Diophantine torus>. Different choices of norm change the constant but not the nature of the condition.