{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2016:PI2IQ4UJWPKGUMTXQXYMSC57DL","short_pith_number":"pith:PI2IQ4UJ","schema_version":"1.0","canonical_sha256":"7a34887289b3d46a327785f0c90bbf1adfe31a262f27d2f8312231ed04472b46","source":{"kind":"arxiv","id":"1605.05274","version":2},"attestation_state":"computed","paper":{"title":"Java Generics are Turing Complete","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.PL","authors_text":"Radu Grigore","submitted_at":"2016-05-17T18:13:37Z","abstract_excerpt":"This paper describes a reduction from the halting problem of Turing machines to subtype checking in Java. It follows that subtype checking in Java is undecidable, which answers a question posed by Kennedy and Pierce in 2007. It also follows that Java's type checker can recognize any recursive language, which improves a result of Gil and Levy from 2016. The latter point is illustrated by a parser generator for fluent interfaces."},"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":"1605.05274","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.PL","submitted_at":"2016-05-17T18:13:37Z","cross_cats_sorted":[],"title_canon_sha256":"be16b0cff319f7220dc8f8baf0536ed9194b3796a6283c8b8d098790fe94abfc","abstract_canon_sha256":"292e25e246486fdc527356ca66f3b0c14186ab8bcbab5f869e6dee82a1c4b84f"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:00:09.404390Z","signature_b64":"QxdDxvVay6fAx2q2XHXSelnZh65/XkzAZOO5wJcaXH/LXN3yQsFfEKc6KAOFXPKYLNiM1WIGKnEylwVSJ0mQBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"7a34887289b3d46a327785f0c90bbf1adfe31a262f27d2f8312231ed04472b46","last_reissued_at":"2026-05-18T01:00:09.403914Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:00:09.403914Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Java Generics are Turing Complete","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.PL","authors_text":"Radu Grigore","submitted_at":"2016-05-17T18:13:37Z","abstract_excerpt":"This paper describes a reduction from the halting problem of Turing machines to subtype checking in Java. It follows that subtype checking in Java is undecidable, which answers a question posed by Kennedy and Pierce in 2007. It also follows that Java's type checker can recognize any recursive language, which improves a result of Gil and Levy from 2016. The latter point is illustrated by a parser generator for fluent interfaces."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1605.05274","kind":"arxiv","version":2},"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"},"aliases":[{"alias_kind":"arxiv","alias_value":"1605.05274","created_at":"2026-05-18T01:00:09.403986+00:00"},{"alias_kind":"arxiv_version","alias_value":"1605.05274v2","created_at":"2026-05-18T01:00:09.403986+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1605.05274","created_at":"2026-05-18T01:00:09.403986+00:00"},{"alias_kind":"pith_short_12","alias_value":"PI2IQ4UJWPKG","created_at":"2026-05-18T12:30:39.010887+00:00"},{"alias_kind":"pith_short_16","alias_value":"PI2IQ4UJWPKGUMTX","created_at":"2026-05-18T12:30:39.010887+00:00"},{"alias_kind":"pith_short_8","alias_value":"PI2IQ4UJ","created_at":"2026-05-18T12:30:39.010887+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL","json":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL.json","graph_json":"https://pith.science/api/pith-number/PI2IQ4UJWPKGUMTXQXYMSC57DL/graph.json","events_json":"https://pith.science/api/pith-number/PI2IQ4UJWPKGUMTXQXYMSC57DL/events.json","paper":"https://pith.science/paper/PI2IQ4UJ"},"agent_actions":{"view_html":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL","download_json":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL.json","view_paper":"https://pith.science/paper/PI2IQ4UJ","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1605.05274&json=true","fetch_graph":"https://pith.science/api/pith-number/PI2IQ4UJWPKGUMTXQXYMSC57DL/graph.json","fetch_events":"https://pith.science/api/pith-number/PI2IQ4UJWPKGUMTXQXYMSC57DL/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL/action/timestamp_anchor","attest_storage":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL/action/storage_attestation","attest_author":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL/action/author_attestation","sign_citation":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL/action/citation_signature","submit_replication":"https://pith.science/pith/PI2IQ4UJWPKGUMTXQXYMSC57DL/action/replication_record"}},"created_at":"2026-05-18T01:00:09.403986+00:00","updated_at":"2026-05-18T01:00:09.403986+00:00"}