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Sound waves move matter

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 نشر من قبل Davison E. Soper
 تاريخ النشر 2019
  مجال البحث فيزياء
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 تأليف Davison E. Soper




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A recent Letter has reported that sound waves can carry gravitational mass. I analyze this effect in a Hookes law solid, considering a wave packet moving in the $z$ direction with an amplitude that is independent of $x$ and $y$. The analysis shows that, at second order in an expansion around small amplitude vibrations, there is a small net motion of material, and thus mass, in the direction opposite to the wave packet propagation. This is a straightforward consequence of Newtons laws.



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