{"title":"Computing functions with parallel queries to NP","authors":"Birgit Jenner, J. Torán","doi":"10.1109/SCT.1993.336519","DOIUrl":"https://doi.org/10.1109/SCT.1993.336519","url":null,"abstract":"The characterizations of the class Theta /sub 2//sup p/ of languages polynomial-time truth-table reducible to sets in NP are surveyed studying the classes obtained when the characterizations are used to define functions instead of languages. It is shown that in this way three function classes are obtained. An overview of the known relationships between these classes, including some original results, is given.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"559 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131445599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The quantitative structure of exponential time","authors":"J. H. Lutz","doi":"10.1109/SCT.1993.336530","DOIUrl":"https://doi.org/10.1109/SCT.1993.336530","url":null,"abstract":"Recent results on the internal, measure-theoretic structure of the exponential time complexity classes E=DTIME(2/sup linear/) and E/sub 2/=DTIME(2/sup polynomial/) are surveyed. The measure structure of these classes is seen to interact in informative ways with bi-immunity, complexity cores, /sub <or=/m/sup P/-reducibility, circuit-size complexity, Kolmogorov complexity, and the density of hard languages. Possible implications for the structure of NP are discussed.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114314542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On limited nondeterminism and the complexity of the V-C dimension","authors":"C. Papadimitriou, M. Yannakakis","doi":"10.1109/SCT.1993.336545","DOIUrl":"https://doi.org/10.1109/SCT.1993.336545","url":null,"abstract":"The complexity of several natural computational problems in NP, which have been proposed but not categorized satisfactorily in the literature is characterized precisely. These problems can be solved in n/sup O(logn)/ time, and thus they are probably not NP-complete. Two new complexity classes between P and NP, very much in the spirit of MAXNP and MAXSNP, are defined. It is shown that computing the V-C dimension is complete for the more general class, whereas the other two problems are complete for the weaker class.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117169957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Relationships between NP-sets, Co-NP-sets, and P-sets relative to random oracles","authors":"N.K. Vereschchagin","doi":"10.1109/SCT.1993.336533","DOIUrl":"https://doi.org/10.1109/SCT.1993.336533","url":null,"abstract":"It is proved that relative to random oracle A (with respect to the uniform measure) the following assertions hold: (1) there is a pair of disjoint NP/sup A/-sets that are separable by no P/sup A/-set, (2) there is a pair of disjoint Co-NP/sup A/-sets that are separable by no P/sup A/-set, and (3) there is an infinite Co-NP/sup A/-set having no infinite NP/sup A/-subset.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114207537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On oracle builder's toolkit","authors":"Stephen A. Fenner, L. Fortnow, S. Kurtz, Lide Li","doi":"10.1109/SCT.1993.336534","DOIUrl":"https://doi.org/10.1109/SCT.1993.336534","url":null,"abstract":"It is shown how to use various notions of genericity as a tool in oracle creation. A general framework for defining different types of generic sets in terms of arithmetic forcing is given. A number of basic facts about Cohen generic sets, many of which are generalizations of known results, are systematically assembled. We define sp-generic sets and extend some previous results.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114230155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Isomorphisms of NP complete problems on random instances","authors":"J. Belanger, Jie Wang","doi":"10.1109/SCT.1993.336540","DOIUrl":"https://doi.org/10.1109/SCT.1993.336540","url":null,"abstract":"Polynomial isomorphisms are defined for NP-complete sets on random instances. Not only are polynomial-time computable and invertible bijections among complete sets considered, but also it is required that these bijections preserve distributions on random instances of these sets. Sufficient conditions for randomized decision problems to be polynomially isomorphic are shown. It is then proved that all the known average-case NP-complete problems under many-one reductions are polynomially isomorphic. These problems include the randomized tiling problem, the randomized halting problem, the randomized Post correspondence problem, and the randomized word problem for Thue systems.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"331 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116234716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Polynomial-time optimization, parallel approximation, and fixpoint logic","authors":"Phokion G. Kolaitis, Madhukar N. Thakur","doi":"10.1109/SCT.1993.336543","DOIUrl":"https://doi.org/10.1109/SCT.1993.336543","url":null,"abstract":"A study of polynomial-time optimization from the perspective of descriptive complexity theory is initiated. It is established that the class of polynomial-time and polynomially bounded optimization problems with ordered finite structures as instances can be characterized in terms of the stage functions of positive first-order formulas, i.e., the functions that compute the number of distinct stages in the bottom-up evaluation of the least fixpoints of such formulas. After this, the stage functions of several first-order formulas whose least fixpoints form natural p-complete problems are studied, and it is shown that they are not NC-approximate within any factor of the optimum, unless P=NC. Finally, it is proved that certain polynomial-time optimization problems are complete with respect to a new kind of restricted reductions that preserve parallel approximability and are definable using quantifier-free formulae.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116759359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Relativized limitations of left set technique and closure classes of sparse sets","authors":"Sanjeev Saluja","doi":"10.1109/SCT.1993.336524","DOIUrl":"https://doi.org/10.1109/SCT.1993.336524","url":null,"abstract":"A number of theorems are proved by introducing the notion of k-families of sets of strings, and an algorithm which outputs the sets of certain k-families is given. The algorithm is used to disjunctively reduce the left set (or 1wdsr set) to a sparse set. The set output by the algorithm on an input corresponds to the set queried by the disjunctive reduction on the input.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127916719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Towards uncheatable benchmarks","authors":"Jin-Yi Cai, R. Lipton, R. Sedgewick, A. Yao","doi":"10.1109/SCT.1993.336546","DOIUrl":"https://doi.org/10.1109/SCT.1993.336546","url":null,"abstract":"The problem of how to make benchmarks resistant to tampering and hence more trustworthy is studied. Some schemes that are based on modern cryptography and complexity theory are proposed to make benchmarks uncheatable. The philosophy is the same as that of encryption-decryption schemes, namely, that trust in individuals and organizations is replaced by trust in the impossibility of breaking certain computational problems.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129173099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"With quasi-linear queries, EXP is not polynomial time Turing reducible to sparse sets","authors":"B. Fu","doi":"10.1109/SCT.1993.336528","DOIUrl":"https://doi.org/10.1109/SCT.1993.336528","url":null,"abstract":"The lower bounds of queries required by the polynomial-time Turing reductions from exponential time classes to the sets of small density are investigated. Results for complexity classes E=DTIME(2/sup linear/) and EXP-DTIME(2/sup poly/) are shown.<<ETX>>","PeriodicalId":331616,"journal":{"name":"[1993] Proceedings of the Eigth Annual Structure in Complexity Theory Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133141988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}