{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T16:43:49Z","timestamp":1767199429259,"version":"build-2238731810"},"reference-count":18,"publisher":"Cambridge University Press (CUP)","issue":"3","license":[{"start":{"date-parts":[[2014,3,12]],"date-time":"2014-03-12T00:00:00Z","timestamp":1394582400000},"content-version":"unspecified","delay-in-days":13706,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. symb. log."],"published-print":{"date-parts":[[1976,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Mostowski [11] shows that if a structure has a decidable theory, then its weak direct power has one as well; his proof however never produces decision procedures which are elementary recursive.<\/jats:p>\n                  <jats:p>Some very general results are obtained here about the nature of the weak direct power of a structure, which in most cases lead to elementary recursive decision procedures for weak direct powers of structures which themselves have elementary recursive procedures.<\/jats:p>\n                  <jats:p>\n                    In particular, it is shown that \u3008\n                    <jats:italic>N<\/jats:italic>\n                    *, +\u3009, the weak direct power of \u3008\n                    <jats:italic>N<\/jats:italic>\n                    , +\u3009, can be decided in space\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:disp-formula>\n                      <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" mime-subtype=\"png\" xlink:href=\"S0022481200051136_eqnU1.png\"\/>\n                    <\/jats:disp-formula>\n                  <\/jats:p>\n                  <jats:p>\n                    for some constant\n                    <jats:italic>c<\/jats:italic>\n                    . As corollaries, the same upper bound is obtained for the theory of the structure \u3008\n                    <jats:italic>N<\/jats:italic>\n                    <jats:sup>+<\/jats:sup>\n                    , \u00b7\u3009 of positive integers under multiplication, and for the theory of finite abelian groups. Fischer and Rabin [7] have shown that the theory of \u3008\n                    <jats:italic>N<\/jats:italic>\n                    ,* +\u3009\n                    <jats:italic>requires time<\/jats:italic>\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:disp-formula>\n                      <jats:graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" mime-subtype=\"png\" xlink:href=\"S0022481200051136_eqnU2.png\"\/>\n                    <\/jats:disp-formula>\n                  <\/jats:p>\n                  <jats:p>even on nondeterministic Turing machines.<\/jats:p>","DOI":"10.2307\/2272034","type":"journal-article","created":{"date-parts":[[2006,5,6]],"date-time":"2006-05-06T17:42:22Z","timestamp":1146937342000},"page":"561-573","source":"Crossref","is-referenced-by-count":2,"title":["On the complexity of the theories of weak direct powers"],"prefix":"10.1017","volume":"41","author":[{"given":"Charles","family":"Rackoff","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"56","published-online":{"date-parts":[[2014,3,12]]},"reference":[{"key":"S0022481200051136_bib017","first-page":"1","volume-title":"5th ACM Syposium on Theory of Computing","author":"Stockmeyer","year":"1973"},{"key":"S0022481200051136_bib002","volume-title":"Computer and logic group memorandum No. 16","author":"Cooper","year":"1972"},{"key":"S0022481200051136_bib018","doi-asserted-by":"publisher","DOI":"10.4064\/fm-41-2-203-271"},{"key":"S0022481200051136_bib008","first-page":"598","volume-title":"Algebra","author":"MacLane","year":"1968"},{"key":"S0022481200051136_bib016","doi-asserted-by":"publisher","DOI":"10.1090\/S0002-9947-1963-0158822-2"},{"key":"S0022481200051136_bib004","doi-asserted-by":"publisher","DOI":"10.1070\/RM1965v020n04ABEH001188"},{"key":"S0022481200051136_bib010","doi-asserted-by":"publisher","DOI":"10.1109\/SWAT.1972.29"},{"key":"S0022481200051136_bib006","doi-asserted-by":"publisher","DOI":"10.1137\/0204006"},{"key":"S0022481200051136_bib001","first-page":"24n30","volume-title":"1964 International Congress for Logic, Methodology, and Philosophy of Science","author":"Cobham","year":"1964"},{"key":"S0022481200051136_bib015","unstructured":"Rackoff, C. W. , The computational complexity of some logical theories, M. I. T. Project MAC Technical report 144, 1975, 130 pp."},{"key":"S0022481200051136_bib003","doi-asserted-by":"publisher","DOI":"10.4064\/fm-49-2-129-141"},{"key":"S0022481200051136_bib005","doi-asserted-by":"publisher","DOI":"10.4064\/fm-47-1-57-103"},{"key":"S0022481200051136_bib011","first-page":"1","volume":"17","author":"Mostowski","year":"1952","journal-title":"On direct powers of theories"},{"key":"S0022481200051136_bib007","volume-title":"Complexity of real computational processes","author":"Fischer","year":"1974"},{"key":"S0022481200051136_bib009","first-page":"23","volume-title":"Boston University Logic Colloquium Proceedings","author":"Meyer"},{"key":"S0022481200051136_bib013","first-page":"300","volume-title":"Recursive functions","author":"P\u00e9ter","year":"1967"},{"key":"S0022481200051136_bib012","first-page":"34","volume-title":"Sth ACM Symposium on Theory of Computing","author":"Oppen","year":"1973"},{"key":"S0022481200051136_bib014","first-page":"395","volume-title":"Comptes Rendus, I Congr\u00e8s des Mathematiciens des Pays Slaves","author":"Presburger","year":"1929"}],"container-title":["The Journal of Symbolic Logic"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0022481200051136","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,3,22]],"date-time":"2023-03-22T06:39:07Z","timestamp":1679467147000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0022481200051136\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1976,9]]},"references-count":18,"aliases":["10.1017\/s0022481200051136"],"journal-issue":{"issue":"3","published-print":{"date-parts":[[1976,9]]}},"alternative-id":["S0022481200051136"],"URL":"https:\/\/doi.org\/10.2307\/2272034","relation":{},"ISSN":["0022-4812","1943-5886"],"issn-type":[{"value":"0022-4812","type":"print"},{"value":"1943-5886","type":"electronic"}],"subject":[],"published":{"date-parts":[[1976,9]]}}}