{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"6819446f4fe6b76e953a9676f9c1d356e43d3d74cfc91f6864d6bd75c9c87bb8","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["b64ec7c0a829f8621b07772b25c87041f3d0b2696fa31986caee08a9a4006adc","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"04d5592808831b6fd6e1cd233fc283e9a1610bb1bf1f210e810f8adcbd0bfcd5","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"cm.driven-dissipative.kpz-2d-condensate","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"A two-dimensional light-matter condensate that is constantly pumped and leaking was predicted to lose long-range coherence at very large distances, unlike an equilibrium superfluid. This prediction lacks a decisive experimental test.","posed_since":"2015","precise":"For a 2D driven-dissipative condensate described by a stochastic complex Ginzburg-Landau equation, phase dynamics maps to the compact KPZ equation, predicting algebraic order only up to a length $L*$ growing exponentially with the inverse nonequilibrium coupling (Altman, Sieberer, Chen, Diehl, Toner 2015). Is the loss of algebraic order beyond $L*$ observed in exciton-polariton condensates, and what replaces it (vortex-dominated disorder or a KPZ-roughened phase)? Answer yes or no, with the large-distance correlation form.","problem_ref":"b64ec7c0a829f8621b07772b25c87041f3d0b2696fa31986caee08a9a4006adc","references":"","settled_by":"Measurement of first-order coherence $g1(r, t)$ in a large uniform 2D polariton condensate showing the crossover from algebraic decay to KPZ or stretched-exponential scaling.","status_note":"$1\\mathrm{D}$ KPZ scaling of the condensate phase was observed in 2022 (Fontaine et al., Nature); a 2026 PRL (Misko, Starkova, Lagoudakis, doi:10.1103/z3ty-255t) reports KPZ physics in optically confined continuous condensates, and its bearing on the $2\\mathrm{D}$ question was not checked.","title":"Does KPZ physics destroy order in two-dimensional polariton condensates?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"9df439039d813cb29d184f78fdc7502c492c08ae1951fed2e43b7a5ce299fa40","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"344189aec2188b3b3626359016474307659a931f7d683b434cd7876c2eb5ce73","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"YApg_-YcxQEIO84Rk0I_k81deXZX_CSaeJ8MbQwKPPUWyY4Ag9eU5Ej2IC-sB65VyuDydIRTx4gwROL-h_jcCA"},"schema":"pubphys.envelope/1"},"record_hash":"9df439039d813cb29d184f78fdc7502c492c08ae1951fed2e43b7a5ce299fa40","leaf_index":2770}