doi:10.1073/pnas.2312880120engBaity-Jesi, MarcoCalore, EnricoCruz, AndrésFernández, Luis AntonioGil-Narvión, José MiguelGonzález-Adalid Pemartín, IsidoroGordillo-Guerrero, AntonioÍñiguez, DavidMaiorano, AndreaMarinari, EnzoMartín-Mayor, VíctorMoreno-Gordo, JavierMuñoz Sudupe, AntonioNavarro, DenisPaga, IlariaParisi, GiorgioPérez-Gaviro, SergioRicci-Tersenghi, FedericoRuiz-Lorenzo, Juan JesúsSchifano, Sebastiano FabioSeoane, BeatrizTarancón, AlfonsoYllanes, DavidMultifractality in spin glassesART-2024-137472We unveil the multifractal behavior of Ising spin glasses in their low-temperature phase. Using the Janus II custom-built supercomputer, the spin-glass correlation function is studied locally. Dramatic fluctuations are found when pairs of sites at the same distance are compared. The scaling of these fluctuations, as the spin-glass coherence length grows with time, is characterized through the computation of the singularity spectrum and its corresponding Legendre transform. A comparatively small number of site pairs controls the average correlation that governs the response to a magnetic field. We explain how this scenario of dramatic fluctuations (at length scales smaller than the coherence length) can be reconciled with the smooth, self-averaging behavior that has long been considered to describe spin-glass dynamics.2024http://zaguan.unizar.es/record/13222810.1073/pnas.2312880120http://zaguan.unizar.es/record/132228oai:zaguan.unizar.es:132228info:eu-repo/grantAgreement/ES/MCIU/FPU18/02665info:eu-repo/grantAgreement/ES/MICINN-AEI-FEDER/PID2019-103939RB-I00info:eu-repo/grantAgreement/ES/MICINN AEI/PID2020-112936GB-I00info:eu-repo/grantAgreement/ES/MICINN AEI/PID2022-136374NB-C21info:eu-repo/grantAgreement/ES/MICINN AEI/PID2022-136374NB-C22info:eu-repo/grantAgreement/ES/MICINN/PGC2018-094684-B-C21info:eu-repo/grantAgreement/ES/MICINN/PGC2018-094684-B-C22info:eu-repo/grantAgreement/ES/MICINN/PID2021-125506NA-I00Proceedings of the National Academy of Sciences of the United States of America 121, 2 (2024), e312880120 [7 pp.]by-nc-ndhttps://creativecommons.org/licenses/by-nc-nd/4.0/deed.esinfo:eu-repo/semantics/openAccess