{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T11:30:21Z","timestamp":1777548621509,"version":"3.51.4"},"reference-count":34,"publisher":"SAGE Publications","issue":"2","license":[{"start":{"date-parts":[[2020,4,16]],"date-time":"2020-04-16T00:00:00Z","timestamp":1586995200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Computability"],"published-print":{"date-parts":[[2020,5,13]]},"abstract":"<jats:p>We study the positions in the Weihrauch lattice of parallel products of various combinatorial principles related to Ramsey\u2019s theorem. Among other results, we obtain an answer to a question of Brattka, by showing that Ramsey\u2019s theorem for pairs ([Formula: see text]) is Weihrauch-incomparable to the parallel product of the stable Ramsey\u2019s theorem for pairs and the cohesive principle ([Formula: see text]).<\/jats:p>","DOI":"10.3233\/com-180203","type":"journal-article","created":{"date-parts":[[2020,4,17]],"date-time":"2020-04-17T12:19:38Z","timestamp":1587125978000},"page":"85-110","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":5,"title":["Ramsey\u2019s theorem and products in the Weihrauch degrees"],"prefix":"10.1177","volume":"9","author":[{"given":"Damir D.","family":"Dzhafarov","sequence":"first","affiliation":[{"name":"Department of Mathematics, University of Wisconsin-Madison, WI, U.S.A."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun Le","family":"Goh","sequence":"additional","affiliation":[{"name":"Department of Mathematics, University of Connecticut, CT, U.S.A.."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Denis R.","family":"Hirschfeldt","sequence":"additional","affiliation":[{"name":"Department of Mathematics, University of Chicago, IL, U.S.A.."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ludovic","family":"Patey","sequence":"additional","affiliation":[{"name":"Institut Camille Jordan, Universit\u00e9 Claude Bernard Lyon 1, France."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arno","family":"Pauly","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Swansea University, U.K.."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2020,4,16]]},"reference":[{"key":"ref001","doi-asserted-by":"publisher","DOI":"10.1016\/j.apal.2016.11.010"},{"key":"ref002","unstructured":"V.\u00a0Brattka, Bibliography on Weihrauch complexity, http:\/\/cca-net.de\/publications\/weibib.php."},{"key":"ref003","doi-asserted-by":"publisher","DOI":"10.1016\/j.apal.2011.10.006"},{"key":"ref004","unstructured":"V.\u00a0Brattka, G.\u00a0Gherardi and A.\u00a0Pauly, Weihrauch complexity in computable analysis, To appear, arXiv:1707.03202."},{"key":"ref005","doi-asserted-by":"publisher","DOI":"10.1007\/s00224-017-9798-1"},{"key":"ref006","unstructured":"V.\u00a0Brattka, R.\u00a0H\u00f6lzl and R.\u00a0Kuyper. Monte Carlo computability, in: 34th Symposium on Theoretical Aspects of Computer Science (STACS 2017), Dagstuhl, Germany, H.\u00a0Vollmer and B.\u00a0Vall\u00e9e, eds, Leibniz International Proceedings in Informatics (LIPIcs), Vol.\u00a066, Schloss Dagstuhl\u2013Leibniz-Zentrum fuer Informatik, 2017, pp.\u00a017:1\u201317:14."},{"issue":"9","key":"ref007","first-page":"77","volume":"5","author":"Brattka V.","year":"2016","journal-title":"Dagstuhl Reports"},{"key":"ref008","doi-asserted-by":"publisher","DOI":"10.1142\/S0219061319500041"},{"issue":"4","key":"ref009","first-page":"1","volume":"14","author":"Brattka V.","year":"2018","journal-title":"Log. Methods Comput. 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