{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.topic/1","content_sha256":"104ff02f93adf521530745ce6f2b989e84f546b689c532620ff80c71a874d69b","created":"2026-10-03T07:17:49Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":[],"salt":"697870e31075cb4db49685117463423582ef9e7fae8eac1a73c2c915dd511088","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"topic"},"content":{"external_id":"amo.constant-variation","field":"amo","n":"1","review_cite":"M. S. Safronova, D. Budker, D. DeMille, D. F. Jackson Kimball, A. Derevianko, C. W. Clark, Search for new physics with atoms and molecules, Reviews of Modern Physics, 2018","review_link":"https://doi.org/10.1103/RevModPhys.90.025008","review_verified":"true","summary":"Numbers like $\\alpha$ and the proton-to-electron mass ratio are assumed fixed, but many theories let them drift slowly or differ across the universe. Comparing atomic clocks over years and reading light from distant quasars tests this.","title":"Do the fundamental constants vary in space or time?","topic_ref":null,"why":"A measured change in any dimensionless constant would violate the equivalence principle and point to new light fields."},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"0d5d25a5bcd4a09341050ed67516a89341dcb76395d21eb07382fa82d8edaaf2","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"3b6331ce368ef3dc903a47b544d5b7b047484b89d51f7d8446bae420e2b6b08e","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"UqlfKwsyZ4VQ-sQnQ3sgSM5UMRTJayr1ubW0G5CokVb_wre8swue8aCWSxFt-9rISDJTEzqx8BUPSWU0zjluCA"},"schema":"pubphys.envelope/1"},"record_hash":"0d5d25a5bcd4a09341050ed67516a89341dcb76395d21eb07382fa82d8edaaf2","leaf_index":8}