2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/205153We study momentum relaxation due to dilute, weak impurities in a strongly coupled CFT, a truncation of the M2 brane theory. Using the AdS/CFT correspondence, we compute the relaxation time scale as a function of the background magnetic field B and charge density ρ. The theory admits two different types of impurities. We find that for magnetic impurities, momentum relaxation due to the impurity is suppressed by a background B or ρ. For electric impurities, due to an underlying instability in the theory towards an ordered phase, the inverse relaxation time scale increases dramatically near \sqrt{B^2 + ρ^2/σ^2_0} \sim 21 T^2. We compute the Nernst response for the impure theory, and comment on similarities with recent measurements in superconductors.26 pages, 11 figures; v2 ref addedHigh Energy Physics - TheoryStrongly Correlated Electronstext