ABSTRACT The anomalous transport of important materials such as high-temperature superconductors and other ‘bad metals’ is not well understood theoretically. In an incoherent metal,

transport is controlled by the collective diffusion of energy and charge rather than by quasiparticle or momentum relaxation. Here, we explore the possibility of a universal bound _D_ ≳

_ℏν_F2/(_k_B_T_) on the underlying diffusion constants in an incoherent metal. Such a bound is loosely motivated by results from holographic duality, the uncertainty principle and

measurements of diffusion in strongly interacting non-metallic systems. Metals close to saturating this bound are shown to have a linear-in-temperature resistivity with an underlying

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support SIMILAR CONTENT BEING VIEWED BY OTHERS RESISTIVITY SATURATION IN KONDO INSULATORS Article Open access 11 October 2021 RISE AND FALL OF LANDAU’S QUASIPARTICLES WHILE APPROACHING THE

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ACKNOWLEDGEMENTS I have benefited greatly from discussions with A. Kapitulnik, G. Kotliar, B. Laughlin, A. Mackenzie, R. McKenzie, V. Oganesyan, J. Orenstein, B. Spivak and especially S. 

Kivelson. S.A.H. is partially financially supported by a DOE Early Career Award and by a Sloan fellowship. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Physics, Stanford

University, Stanford, California 94305-4060, USA Sean A. Hartnoll Authors * Sean A. Hartnoll View author publications You can also search for this author inPubMed Google Scholar

CORRESPONDING AUTHOR Correspondence to Sean A. Hartnoll. ETHICS DECLARATIONS COMPETING INTERESTS The author declares no competing financial interests. RIGHTS AND PERMISSIONS Reprints and

permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Hartnoll, S. Theory of universal incoherent metallic transport. _Nature Phys_ 11, 54–61 (2015). https://doi.org/10.1038/nphys3174 Download

citation * Received: 24 July 2014 * Accepted: 30 October 2014 * Published: 23 December 2014 * Issue Date: January 2015 * DOI: https://doi.org/10.1038/nphys3174 SHARE THIS ARTICLE Anyone you

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