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تسجيل مستخدم جديدWigner transform and quasicrystals
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Quasicrystals are tempered distributions $mu$ which satisfy symmetric conditions on $mu$ and $widehat mu$. This suggests that techniques from time-frequency analysis could possibly be useful tools in the study of such structures. In this paper we explore this direction considering quasicrystals type conditions on time-frequency representations instead of separately on the distribution and its Fourier transform. More precisely we prove that a tempered distribution $mu$ on ${mathbb R}^d$ whose Wigner transform, $W(mu)$, is supported on a product of two uniformly discrete sets in ${mathbb R}^d$ is a quasicrystal. This result is partially extended to a generalization of the Wigner transform, called matrix-Wigner transform which is defined in terms of the Wigner transform and a linear map $T$ on ${mathbb R}^{2d}$.
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