Results 1 to 10 of about 789 (36)
Modeling Complex Systems by Structural Invariants Approach
Complexity, 2021 When modeling complex systems, we usually encounter the following difficulties: partiality, large amount of data, and uncertainty of conclusions. It can be said that none of the known approaches solves these difficulties perfectly, especially in cases ...
Jiri Bila, Ali. H. Reshak, Jan Chysky
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Kinds of Pregeometries of Acyclic Theories
Известия Иркутского государственного университета: Серия "Математика", 2023 The article is devoted to the description of types of pregeometries with an algebraic closure operator for acyclic theories. In these theories we describe conditions of violation of the exchange property for a pregeometry.
S. B. Malyshev
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Pregeometry and euclidean quantum gravity
Nuclear Physics B, 2021 Einstein's general relativity can emerge from pregeometry, with the metric composed of more fundamental fields. We formulate euclidean pregeometry as a SO(4) - Yang-Mills theory.
Christof Wetterich
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On atomic and algebraically prime models obtained by closure of definable sets
Қарағанды университетінің хабаршысы. Математика сериясы, 2021 This article discusses the properties of atomic and prime models obtained with the some closure operator given on definable subsets of the semantic model some fixed Jonsson theory.
A.R. Yeshkeyev +2 more
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Kinds of Pregeometries of Cubic Theories
Известия Иркутского государственного университета: Серия "Математика", 2022 The description of the types of geometries is one of the main problems in the structural classification of algebraic systems. In addition to the well-known classical geometries, a deep study of the main types of pregeometries and geometries was carried ...
S. B. Malyshev
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An Overview of Saharon Shelah's Contributions to Mathematical Logic, in Particular to Model Theory
Theoria, Volume 87, Issue 2, Page 349-360, April 2021., 2021 Abstract I will give a brief overview of Saharon Shelah's work in mathematical logic. I will focus on three transformative contributions Shelah has made: stability theory, proper forcing and PCF theory. The first is in model theory and the other two are in set theory.
Jouko Väänänen
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Nuclear Physics B, 2021 We propose fundamental scale invariance as a new theoretical principle beyond renormalizability. Quantum field theories with fundamental scale invariance admit a scale-free formulation of the functional integral and effective action in terms of scale ...
C. Wetterich
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Pregeometry and spontaneous time-space asymmetry
Journal of High Energy Physics, 2022 In pregeometry a metric arises as a composite object at large distances. We investigate if its signature, which distinguishes between time and space, could be a result of the dynamics rather than being built in already in the formulation of a model.
C. Wetterich
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Properties of hybrids of Jonsson theories
Қарағанды университетінің хабаршысы. Математика сериясы, 2018 This work is an introduction to the study of the properties of a new concept, as a hybrid of Jonsson theories. We define the basic concepts and framework for studying the model-theoretic properties of these concepts.
A.R. Yeshkeyev, N.M. Mussina
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Waves on Noncommutative Spacetime and Gamma-Ray Bursts [PDF]
, 1999 Quantum group Fourier transform methods are applied to the study of processes on noncommutative Minkowski spacetime $[x^i,t]=\imath\lambda x^i$. A natural wave equation is derived and the associated phenomena of {\it in vacuo} dispersion are discussed ...
Amelino-Camelia G. +9 more
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