{"paper":{"title":"A universal Kripke frame for the variable-free fragment of RC$^\\nabla$","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"math.LO","authors_text":"Lev D. Beklemishev","submitted_at":"2018-04-08T07:42:28Z","abstract_excerpt":"This note characterizes a universal Kripke frame for the variable-free fragment of the reflection calculus with conservativity operators RC$^\\nabla$. The frame here is obtained from the set of all filters on the Ignatiev RC$^\\nabla$-algebra which is an isomorphic presentation of the Lindenbaum--Tarski algebra of the variable-free fragment of RC$^\\nabla$. We give a constructive `coordinatewise' characterization of the set of filters and of the frame relations corresponding to the modalities of the algebra."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1804.02641","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}