{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"f077dd1adc5b2f4431ba773e04f7fe8d740183648753d54754821b7961272cab","created":"2026-10-03T07:18:10Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"f8249793789b38ad4fe23dd46ff83ecf186f3021b723fa2abb83c796bbf08853","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"stat.fput-thermalization.disordered-packet-spreading","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"In a disordered lattice without interactions, waves stay trapped in place (Anderson localization). Weak nonlinearity lets a packet slowly spread, and it is unknown whether the spreading continues forever or eventually stops.","posed_since":"2008","precise":"For the disordered discrete nonlinear Schrodinger equation i dpsi_n/dt = eps_n psi_n + beta |psi_n|^2 psi_n - (psi_(n+1) + psi_(n-1)) with i.i.d. random eps_n, and the analogous Klein-Gordon chain, determine whether the second moment $m_2(t)$ of an initially localized packet diverges as $t \\to \\infty$ (simulations show $m_2 \\sim t^{1/3}$ over many decades) or saturates once the packet density falls below a chaos threshold. Answer: yes or no, with the asymptotic law.","problem_ref":null,"references":"","settled_by":"A proof of unbounded or bounded spreading, or simulations long enough to show a clear departure from or persistence of subdiffusion with a theory for the observed law.","status_note":"","title":"Endless spreading of wave packets in disordered nonlinear lattices","topic_ref":"b026e7f128afdc43ebc73cc909210ea680a0ba040cd45dc5b34d5a420020f836"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"0e4461e6479310dd44b1de52f6abcb1f21caa6ecd7c429728b81a6d17702d689","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"f1597aaea1196216758e372affa9f9609f42ddbafc8a0b2b40800f83a3c913d6","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"YjRzuzzNv5EFcJeiWKlDAE9Jy3EtJKgM9zTa8jNgADbOZTvNnRWcmEZVjcnOXWHPbM_SFUE-u41XHmVIbMJkCg"},"schema":"pubphys.envelope/1"},"record_hash":"0e4461e6479310dd44b1de52f6abcb1f21caa6ecd7c429728b81a6d17702d689","leaf_index":2078}