According to modern understanding, sliding friction is caused by the displacement of the irregularities and individual atoms in the interaction zone of the sliding interfaces, leading to microscopic oscillations around the equilibrium position (the stick/slip model of Tomlinson). This is in contrast to the traditional account of sliding friction (static interlocking asperities), which in fact is insufficient (see online Appendix for more information about the theoretical background and its development).

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Supplementary Material

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