{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.topic/1","content_sha256":"1a7a21f8c24fa1e3cfd7e9c91ee44286bcccfe16e800a5c369535f39cdeeffa3","created":"2026-10-03T07:17:52Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":[],"salt":"b4b8739a0de0f4231f20d725ff0ee5677a5fdc5ba8b18c3cba75fcbccb11ae70","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"topic"},"content":{"external_id":"plasma.vacuum-birefringence-schwinger","field":"plasma","n":"1","review_cite":"R. Battesti, C. Rizzo, Magnetic and electric properties of a quantum vacuum, Reports on Progress in Physics, 2013","review_link":"https://doi.org/10.1088/0034-4885/76/1/016401","review_verified":"true","summary":"Quantum theory predicts that empty space, filled with short-lived virtual electron-positron pairs, should slow light differently depending on its polarization when a strong field is present, and should break down into real electrons and positrons in a strong enough field. Neither effect has been seen unambiguously in a laboratory with macroscopic fields.","title":"Laboratory vacuum birefringence and Schwinger pair creation","topic_ref":null,"why":"These are the defining nonlinear properties of the QED vacuum, predicted since the 1930s to 1950s and still untested directly."},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"55a07bba1dfa71f7b80f75c8b6d22d8d64b8456a647eee5719b5c98b8b9ea3c9","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"96b3a8b73cd301445d1e12b776ad0fa1d3c8dd9e20a5800bb0ddb500c9812b3a","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"3B4MqHD61tecW6nyKx8EygZNqPMRFko2sLry_UAGZVRK5LFtSzsQ93bFzZQAbBoL9pIZEq2MXukEHkraXCHLCw"},"schema":"pubphys.envelope/1"},"record_hash":"55a07bba1dfa71f7b80f75c8b6d22d8d64b8456a647eee5719b5c98b8b9ea3c9","leaf_index":309}