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A particular interest attracts its subset $M^o(P) \\subset M(P)$ of all configurations \\emph{without} self-intersections. R. Connelly, E. Demaine, and G. Rote proved that $M^o(P)$ is contractible and conjectured that so is its closure $\\bar{M^o(P)}$. We disprove this conjecture by showing that a special choice of $P$ makes the homologies $H_k(\\bar{M^o(P)})$ non-trivial."},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"1106.1134","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.AT","submitted_at":"2011-06-06T18:01:33Z","cross_cats_sorted":[],"title_canon_sha256":"b13e46dc1c9eb0d058e6f548af80f28c82ed46de6ab53a276ea21d3ffb3b00a5","abstract_canon_sha256":"c5c8ac1a234bc06efad2060dacf64d993d774eeaf58ac68d040533575757ea4a"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:20:06.333786Z","signature_b64":"vraSCOp8i8JKcL+gdKWc5kl8nqxp5Js1Yq9DfPPn78EdkJ8gZX1IHa+9Hxk8EGKrqW4hJB/equ24aD3EQRZXDg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"ac2d5facd4b00c6480d833cb2d1f24848986b96f227ced536de0c6d4c6e7e482","last_reissued_at":"2026-05-18T04:20:06.333322Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:20:06.333322Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Around a conjecture by R. 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