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تسجيل مستخدم جديدAnomalous Elasticity in Frictional Matter
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In a recent paper [Phys. Rev. E {bf 104}, 024904] it was shown that mechanical strains in amorphous solids are screened via the formation of plastic events that are typically quadrupolar in nature. At low densities the screening effect is reminiscent of the role of dipoles in dielectrics, while the effect at high density has no immediate electrostatic analog, and is expected to change qualitatively the mechanical response, as seen for example in the displacement field. In this Letter we show that high-density screening results in undulating displacement field that strictly deviate from elasticity theory. We show that theoretical analysis, experimental measurements and numeric simulations of frictional granular amorphous assemblies are in agreement with each other and provide a strong support for the theory.
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