Paper

{
  "raw_xml": "<entry>\n    <id>http://arxiv.org/abs/2602.21901v1</id>\n    <title>Computing Nonequilibrium Transport from Short-Time Transients: From Lorentz Gas to Heat Conduction in One Dimensional Chains</title>\n    <updated>2026-02-25T13:31:56Z</updated>\n    <link href='https://arxiv.org/abs/2602.21901v1' rel='alternate' type='text/html'/>\n    <link href='https://arxiv.org/pdf/2602.21901v1' rel='related' title='pdf' type='application/pdf'/>\n    <summary>We test the Transient Time Correlation Function (TTCF) method to compute nonequilibrium transport coefficients, highlighting its conceptual and practical difference from the standard time-average approach. While time averages extract transport properties from long stationary trajectories and discard transient dynamics, TTCF adopts the complementary strategy: it exploits the information contained in short-time transients following the onset of an external perturbation, while discarding the long-time evolution once stationarity is reached. We revisit the theoretical framework of TTCF and assess its numerical performance through representative case studies, the Lorentz gas and a many-body system, namely a chain of oscillators with anharmonic pinning potential. By direct comparison with time averages, we show that for the Lorentz gas TTCF yields consistent transport coefficients in both linear and nonlinear regimes at a reduced computational cost. Moreover, the TTCF displays superior precision in the linear-response regime, and remains reliable in non-ergodic situations, revealing the presence of regions of phase space corresponding to different behaviors, as well as the possibility of phase transitions. For the anharmonic chain, we show that TTCF is a scalable and efficient alternative for the numerical study of nonequilibrium transport.</summary>\n    <category scheme='http://arxiv.org/schemas/atom' term='cond-mat.stat-mech'/>\n    <category scheme='http://arxiv.org/schemas/atom' term='math-ph'/>\n    <category scheme='http://arxiv.org/schemas/atom' term='physics.comp-ph'/>\n    <published>2026-02-25T13:31:56Z</published>\n    <arxiv:primary_category term='cond-mat.stat-mech'/>\n    <author>\n      <name>Davide Carbone</name>\n      <arxiv:affiliation>Laboratoire de Physique de l'Ecole Normale Superieure, ENS Universite PSL, CNRS, Sorbonne Universite, Universite de Paris, Paris, France</arxiv:affiliation>\n    </author>\n    <author>\n      <name>Vincenzo Di Florio</name>\n      <arxiv:affiliation>MOX Laboratory, Department of Mathematics, Politecnico di Milano, Piazza Leonardo Da Vinci 32, 20133 Milano, Italy</arxiv:affiliation>\n      <arxiv:affiliation>CONCEPT Lab, Fondazione Istituto Italiano di Tecnologia, Via E. Melen 83, Genova, 16152, Italy</arxiv:affiliation>\n    </author>\n    <author>\n      <name>Stefano Lepri</name>\n      <arxiv:affiliation>Consiglio Nazionale delle Ricerche, Istituto dei Sistemi Complessi, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy</arxiv:affiliation>\n      <arxiv:affiliation>INFN, Sezione di Firenze, Via G. Sansone 1, 50019 Sesto Fiorentino, Italy</arxiv:affiliation>\n    </author>\n    <author>\n      <name>Lamberto Rondoni</name>\n      <arxiv:affiliation>INFN, Sezione di Torino, Via P. Giuria 1, 10125 Torino, Italy</arxiv:affiliation>\n      <arxiv:affiliation>Dipartimento di Scienze Matematiche, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy</arxiv:affiliation>\n    </author>\n  </entry>"
}