{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"ab4af8821ac9ed806e08137099bc9640e0eb84fc8e3f2483bc0ba17fac8b0ce2","created":"2026-10-03T07:18:10Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"84e02a953cf230f33d0547bd92d90488878b0cd946433c5cec56d3d08d6ab251","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"qi.macro-superpositions.leggett-garg-massive","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"Macrorealism is the everyday assumption that a large object always has a definite state that can be checked without disturbing it. A Leggett-Garg test checks this by measuring one object at several times; a convincing test with a heavy mechanical object is missing.","posed_since":"1985","precise":"For a mechanical mode of effective mass $m\\ge 1e-6\\,\\mathrm{g}$, measure two-time correlators $C_{ij}$ of a two-valued observable at $t_1<t_2<t_3$ and test $K=C_{12}+C_{23}-C_{13}\\le 1$, using ideal negative-result or control-experiment protocols that close the clumsiness loophole (disturbance by the measurement itself). An answer is $K>1$ at stated significance with invasiveness bounded by independent controls.","problem_ref":null,"references":"","settled_by":"A loophole-controlled Leggett-Garg violation on a microgram-scale mechanical mode.","status_note":"Cat states of a 16 microgram bulk acoustic resonator were made in 2023 (Bild et al., Science); no loophole-controlled Leggett-Garg test at such masses was found in the literature checked.","title":"Leggett-Garg violation with a massive mechanical oscillator","topic_ref":"da67c360563bebb459ce77935d96142fdf67da34e3b4e3efdde15ae56291e12f"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"5d27ad3a73f68b2d609f70299eaf28900b3e115f8e9dee5b2f1a43025a119244","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"f523defc986f8b25b61571eb185a41a0a2ae2689c4befeb099b927fba1c73bbc","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"9sR2y6V7N5TaoGN9XomATy_nIZueS46_mU0jqo8burYsv64Ef6kXudzn7vnaQ3BMFeQkQcJMZEEySJKKzMnTCQ"},"schema":"pubphys.envelope/1"},"record_hash":"5d27ad3a73f68b2d609f70299eaf28900b3e115f8e9dee5b2f1a43025a119244","leaf_index":2009}