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On the optimal constants in Korns and geometric rigidity estimates, in bounded and unbounded domains, under Neumann boundary conditions

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 نشر من قبل Marta Lewicka
 تاريخ النشر 2015
  مجال البحث
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We are concerned with the optimal constants: in the Korn inequality under tangential boundary conditions on bounded sets $Omega subset mathbb{R}^n$, and in the geometric rigidity estimate on the whole $mathbb{R}^2$. We prove that the latter constant equals $sqrt{2}$, and we discuss the relation of the former constants with the optimal Korns constants under Dirichlet boundary conditions, and in the whole $mathbb{R}^n$, which are well known to equal $sqrt{2}$. We also discuss the attainability of these constants and the structure of deformations/displacement fields in the optimal sets.

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