20 found
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  1.  45
    Omitting types and AF algebras.Kevin Carlson, Enoch Cheung, Ilijas Farah, Alexander Gerhardt-Bourke, Bradd Hart, Leanne Mezuman, Nigel Sequeira & Alexander Sherman - 2014 - Archive for Mathematical Logic 53 (1):157-169.
    We prove that the classes of UHF algebras and AF algebras, while not axiomatizable, can be characterized as those C*-algebras that omit certain types in the logic of metric structures.
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  2.  17
    The Universal Theory of the Hyperfinite II $_1$ Factor is Not Computable.Isaac Goldbring & Bradd Hart - 2024 - Bulletin of Symbolic Logic 30 (2):181-198.
    We show that the universal theory of the hyperfinite II $_1$ factor is not computable. The proof uses the recent result that MIP*=RE. Combined with an earlier observation of the authors, this yields a proof that the Connes Embedding Problem has a negative solution that avoids the equivalences with Kirchberg’s QWEP Conjecture and Tsirelson’s Problem.
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  3.  38
    Fraïssé Limits of C*-Algebras.Christopher J. Eagle, Ilijas Farah, Bradd Hart, Boris Kadets, Vladyslav Kalashnyk & Martino Lupini - 2016 - Journal of Symbolic Logic 81 (2):755-773.
    We realize the Jiang-Su algebra, all UHF algebras, and the hyperfinite II1factor as Fraïssé limits of suitable classes of structures. Moreover by means of Fraïssé theory we provide new examples of AF algebras with strong homogeneity properties. As a consequence of our analysis we deduce Ramsey-theoretic results about the class of full-matrix algebras.
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  4.  20
    Computability and the connes embedding problem.Isaac Goldbring & Bradd Hart - 2016 - Bulletin of Symbolic Logic 22 (2):238-248.
    The Connes Embedding Problem asks whether every separable II1 factor embeds into an ultrapower of the hyperfinite II1 factor. We show that the CEP is equivalent to the statement that every type II1 tracial von Neumann algebra has a computable universal theory.
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  5.  66
    A Structure Theorem for Strongly Abelian Varieties with Few Models.Bradd Hart & Matthew Valeriote - 1991 - Journal of Symbolic Logic 56 (3):832.
  6.  77
    A proof of morley's conjecture.Bradd Hart - 1989 - Journal of Symbolic Logic 54 (4):1346-1358.
  7.  59
    Models with second order properties V: A general principle.Saharon Shelah, Claude Laflamme & Bradd Hart - 1993 - Annals of Pure and Applied Logic 64 (2):169-194.
    Shelah, S., C. Laflamme and B. Hart, Models with second order properties V: A general principle, Annals of Pure and Applied Logic 64 169–194. We present a general framework for carrying out the construction in [2-10] and others of the same type. The unifying factor is a combinatorial principle which we present in terms of a game in which the first player challenges the second player to carry out constructions which would be much easier in a generic extension of the (...)
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  8.  24
    An Unclassifiable Unidimensional Theory without OTOP.Ambar Chowdhury & Bradd Hart - 1997 - Notre Dame Journal of Formal Logic 38 (1):93-103.
    A countable unidimensional theory without the omitting types order property (OTOP) has prime models over pairs and is hence classifiable. We show that this is not true for uncountable unidimensional theories.
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  9.  99
    On the Type-Definability of the Binding Group in Simple Theories.Bradd Hart & Ziv Shami - 2005 - Journal of Symbolic Logic 70 (2):379 - 388.
    Let T be simple, work in Ceq over a boundedly closed set. Let p ∈ S(θ) be internal in a quasi-stably-embedded type-definable set Q (e.g., Q is definable or stably-embedded) and suppose (p, Q) is ACL-embedded in Q (see definitions below). Then Aut(p/Q) with its action on pC is type-definable in Ceq over θ. In particular, if p ∈ S(θ) is internal in a stably-embedded type-definable set Q, and pC υ Q is stably-embedded, then Aut(p/Q) is type-definable with its action (...)
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  10.  43
    The theory of tracial von Neumann algebras does not have a model companion.Isaac Goldbring, Bradd Hart & Thomas Sinclair - 2013 - Journal of Symbolic Logic 78 (3):1000-1004.
  11.  36
    1997–98 Annual Meeting of the Association for Symbolic Logic.Bradd Hart - 1998 - Bulletin of Symbolic Logic 4 (4):443-458.
  12.  55
    A note on a-prime models.Bradd Hart, Zeljko Sokolovic & Predrag Tanovic - 1999 - Journal of Symbolic Logic 64 (4):1557-1562.
    We answer a question of Cassidy and Kolchin about the universality of the constrained closure of a differential field by working in a larger category of models.
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  13.  36
    (1 other version)Addendum to "a structure theorem for strongly Abelian varieties".Bradd Hart & Sergei Starchenko - 1993 - Journal of Symbolic Logic 58 (4):1419-1425.
  14.  41
    2012 north american annual meeting of the association for symbolic logic.Bradd Hart - forthcoming - Bulletin of Symbolic Logic.
  15.  59
    Unique decomposition in classifiable theories.Bradd Hart, Ehud Hrushovski & Michael C. Laskowski - 2002 - Journal of Symbolic Logic 67 (1):61-68.
  16.  60
    Review: Frank O. Wagner, Simple Theories. [REVIEW]Bradd Hart - 2002 - Bulletin of Symbolic Logic 8 (4):522-524.
  17.  18
    Enrique Casanovas. Simple theories and hyperimaginaries. Lecture Notes in Logic, vol. 39. ASL and Cambridge University Press, Cambridge, 2011, 184 pp. [REVIEW]Bradd Hart - 2012 - Bulletin of Symbolic Logic 18 (3):405-406.
  18.  26
    K. Tent and M. Ziegler. A Course in Model Theory. Lecture Notes in Logic, vol. 40. Cambridge University Press, United Kingdom, 2012, x + 248 pp. [REVIEW]Bradd Hart - 2015 - Bulletin of Symbolic Logic 21 (3):342-343.
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  19.  22
    2012 North American Annual Meeting of the Association for Symbolic Logic, University of Wisconsin, Madison, WI, USA, March 31–April 3, 2012. [REVIEW]Bradd Hart - 2013 - Bulletin of Symbolic Logic 19 (2):236-256.
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  20.  12
    (1 other version)Shelah S.. Classification theory and the number of non-isomorphic models. Revised edition of XLVII 694. Studies in logic and the foundations of mathematics, vol. 92. North-Holland, Amsterdam etc. 1990, xxxiv + 705 pp. [REVIEW]Bradd Hart - 1993 - Journal of Symbolic Logic 58 (3):1071-1074.
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