{
  "abstract": "The Generalized Langevin Equation (GLE) is an integro-differential equation of motion for a general observable of a many-body system and is rigorously derived using the projection operator formalism. In the standard derivation, a stationary canonical phase space distribution is used for the projection. Here, we derive a novel class of GLEs using a non-stationary projection distribution that constrains the initial ensemble to a hypersurface in phase space on which the observable has a fixed value $A_0$. As a result, all GLE parameters, and in particular the memory friction kernel, depend on $A_0$ and can be extracted from short simulations that do not sample the entire phase space. Applying this non-stationary GLE to protein folding trajectories, we find for villin and an $α$-helical poly-alanine segment that the total friction is higher in the folded state. These results demonstrate that observable-dependent friction effects are non-negligible and can be accounted for using non-stationary GLEs derived by constrained projection schemes.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.28113",
  "author_total": 6,
  "authors": [
    {
      "name": "Salma Salem"
    },
    {
      "name": "Lucas Tepper"
    },
    {
      "name": "Benjamin J. A. Héry"
    },
    {
      "name": "Henrik Kiefer"
    },
    {
      "name": "David D. Girardier"
    },
    {
      "name": "Roland R. Netz"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b88arhaa4ax0n.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.28113",
  "fulltext_url": null,
  "id": "b88arhaa4ax0n",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.28113",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.soft"
    ],
    [
      "arxiv",
      "cond-mat.stat-mech"
    ],
    [
      "arxiv",
      "physics.bio-ph"
    ],
    [
      "openalex",
      "1312|Protein Structure and Dynamics"
    ]
  ],
  "openalex": "W7214152446",
  "pdf_url": "https://arxiv.org/pdf/2609.28113",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-23",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/b88arhaa4ax0n.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:56Z",
      "native_id": "2609.28113",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.28113"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.bio-ph",
      "subfield": "biological-medical"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.soft",
      "subfield": "condensed-matter"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.stat-mech",
      "subfield": "statistical-nonlinear"
    }
  ],
  "title": "Position-dependent friction in protein folding from a GLE derived with a non-stationary localized projection distribution",
  "title_text": "Position-dependent friction in protein folding from a GLE derived with a non-stationary localized projection distribution",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:56Z",
  "url": "https://research.draconitic.com/paper/b88arhaa4ax0n",
  "venue": "arXiv",
  "versions": []
}