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Quaternionic slice hyperbolic backward shift operators and adaptive greedy algorithm

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 نشر من قبل Jin Ming
 تاريخ النشر 2021
  مجال البحث
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In the slice Hardy space over the unit ball of quaternions, we introduce the slice hyperbolic backward shift operators $mathcal S_a$ based on the identity $$f=e_alangle f, e_arangle+B_{a}*mathcal S_a f,$$ where $e_a$ denotes the slice normalized Szego kernel and $ B_a $ the slice Mobius transformation. By iterating the identity above, the greedy algorithm gives rise to the slice adaptive Fourier decomposition via maximum selection principle. This leads to the slice Takenaka-Malmquist orthonormal system.

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