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Quasinormal modes and shadow of noncommutative black hole

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 نشر من قبل Francisco A. Brito
 تاريخ النشر 2021
  مجال البحث فيزياء
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In this paper we investigate quasinormal modes (QNM) for a scalar field around a noncommutative Schwarzschild black hole. We verify the effect of noncommutativity on quasinormal frequencies by applying two procedures widely used in the literature. The first is the Wentzel-Kramers-Brillouin (WKB) approximation up to sixth order. In the second case we use the continuous fraction method developed by Leaver. We find that the quasinormal frequencies obtained for nonzero noncommutative parameter resemble those of the Reissner-Nordstr{o}m geometry. Besides, we also show that due to noncommutativity, the shadow radius is reduced when we increase the noncommutative parameter. In addition, we find that the shadow radius is nonzero even at the zero mass limit for finite noncommutative parameter.

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