Why Philosophers Should Care About Computational Complexity
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Advances in Theoretical & Computational Physics
ISSN: 2639-0108 Review Article Advances in Theoretical & Computational Physics Cosmology: Preprogrammed Evolution (The problem of Providence) Besud Chu Erdeni Unified Theory Lab, Bayangol disrict, Ulan-Bator, Mongolia *Corresponding author Besud Chu Erdeni, Unified Theory Lab, Bayangol disrict, Ulan-Bator, Mongolia. Submitted: 25 March 2021; Accepted: 08 Apr 2021; Published: 18 Apr 2021 Citation: Besud Chu Erdeni (2021) Cosmology: Preprogrammed Evolution (The problem of Providence). Adv Theo Comp Phy 4(2): 113-120. Abstract This is continued from the article Superunification: Pure Mathematics and Theoretical Physics published in this journal and intended to discuss the general logical and philosophical consequences of the universal mathematical machine described by the superunified field theory. At first was mathematical continuum, that is, uncountably infinite set of real numbers. The continuum is self-exited and self- organized into the universal system of mathematical harmony observed by the intelligent beings in the Cosmos as the physical Universe. Consequently, cosmology as a science of evolution in the Uni- verse can be thought as a preprogrammed natural phenomenon beginning with the Big Bang event, or else, the Creation act pro- (6) cess. The reader is supposed to be acquinted with the Pythagoras’ (Arithmetization) and Plato’s (Geometrization) concepts. Then, With this we can derive even the human gene-chromosome topol- the numeric, Pythagorean, form of 4-dim space-time shall be ogy. (1) The operator that images the organic growth process from nothing is where time is an agorithmic (both geometric and algebraic) bifur- cation of Newton’s absolute space denoted by the golden section exp exp e. -
Journal of Computational Physics
JOURNAL OF COMPUTATIONAL PHYSICS AUTHOR INFORMATION PACK TABLE OF CONTENTS XXX . • Description p.1 • Audience p.2 • Impact Factor p.2 • Abstracting and Indexing p.2 • Editorial Board p.2 • Guide for Authors p.6 ISSN: 0021-9991 DESCRIPTION . Journal of Computational Physics has an open access mirror journal Journal of Computational Physics: X which has the same aims and scope, editorial board and peer-review process. To submit to Journal of Computational Physics: X visit https://www.editorialmanager.com/JCPX/default.aspx. The Journal of Computational Physics focuses on the computational aspects of physical problems. JCP encourages original scientific contributions in advanced mathematical and numerical modeling reflecting a combination of concepts, methods and principles which are often interdisciplinary in nature and span several areas of physics, mechanics, applied mathematics, statistics, applied geometry, computer science, chemistry and other scientific disciplines as well: the Journal's editors seek to emphasize methods that cross disciplinary boundaries. The Journal of Computational Physics also publishes short notes of 4 pages or less (including figures, tables, and references but excluding title pages). Letters to the Editor commenting on articles already published in this Journal will also be considered. Neither notes nor letters should have an abstract. Review articles providing a survey of particular fields are particularly encouraged. Full text articles have a recommended length of 35 pages. In order to estimate the page limit, please use our template. Published conference papers are welcome provided the submitted manuscript is a significant enhancement of the conference paper with substantial additions. Reproducibility, that is the ability to reproduce results obtained by others, is a core principle of the scientific method. -
Efficient Algorithms with Asymmetric Read and Write Costs
Efficient Algorithms with Asymmetric Read and Write Costs Guy E. Blelloch1, Jeremy T. Fineman2, Phillip B. Gibbons1, Yan Gu1, and Julian Shun3 1 Carnegie Mellon University 2 Georgetown University 3 University of California, Berkeley Abstract In several emerging technologies for computer memory (main memory), the cost of reading is significantly cheaper than the cost of writing. Such asymmetry in memory costs poses a fun- damentally different model from the RAM for algorithm design. In this paper we study lower and upper bounds for various problems under such asymmetric read and write costs. We con- sider both the case in which all but O(1) memory has asymmetric cost, and the case of a small cache of symmetric memory. We model both cases using the (M, ω)-ARAM, in which there is a small (symmetric) memory of size M and a large unbounded (asymmetric) memory, both random access, and where reading from the large memory has unit cost, but writing has cost ω 1. For FFT and sorting networks we show a lower bound cost of Ω(ωn logωM n), which indicates that it is not possible to achieve asymptotic improvements with cheaper reads when ω is bounded by a polynomial in M. Moreover, there is an asymptotic gap (of min(ω, log n)/ log(ωM)) between the cost of sorting networks and comparison sorting in the model. This contrasts with the RAM, and most other models, in which the asymptotic costs are the same. We also show a lower bound for computations on an n × n diamond DAG of Ω(ωn2/M) cost, which indicates no asymptotic improvement is achievable with fast reads. -
On the Randomness Complexity of Interactive Proofs and Statistical Zero-Knowledge Proofs*
On the Randomness Complexity of Interactive Proofs and Statistical Zero-Knowledge Proofs* Benny Applebaum† Eyal Golombek* Abstract We study the randomness complexity of interactive proofs and zero-knowledge proofs. In particular, we ask whether it is possible to reduce the randomness complexity, R, of the verifier to be comparable with the number of bits, CV , that the verifier sends during the interaction. We show that such randomness sparsification is possible in several settings. Specifically, unconditional sparsification can be obtained in the non-uniform setting (where the verifier is modelled as a circuit), and in the uniform setting where the parties have access to a (reusable) common-random-string (CRS). We further show that constant-round uniform protocols can be sparsified without a CRS under a plausible worst-case complexity-theoretic assumption that was used previously in the context of derandomization. All the above sparsification results preserve statistical-zero knowledge provided that this property holds against a cheating verifier. We further show that randomness sparsification can be applied to honest-verifier statistical zero-knowledge (HVSZK) proofs at the expense of increasing the communica- tion from the prover by R−F bits, or, in the case of honest-verifier perfect zero-knowledge (HVPZK) by slowing down the simulation by a factor of 2R−F . Here F is a new measure of accessible bit complexity of an HVZK proof system that ranges from 0 to R, where a maximal grade of R is achieved when zero- knowledge holds against a “semi-malicious” verifier that maliciously selects its random tape and then plays honestly. -
Computability of Fraïssé Limits
COMPUTABILITY OF FRA¨ISSE´ LIMITS BARBARA F. CSIMA, VALENTINA S. HARIZANOV, RUSSELL MILLER, AND ANTONIO MONTALBAN´ Abstract. Fra¨ıss´estudied countable structures S through analysis of the age of S, i.e., the set of all finitely generated substructures of S. We investigate the effectiveness of his analysis, considering effectively presented lists of finitely generated structures and asking when such a list is the age of a computable structure. We focus particularly on the Fra¨ıss´elimit. We also show that degree spectra of relations on a sufficiently nice Fra¨ıss´elimit are always upward closed unless the relation is definable by a quantifier-free formula. We give some sufficient or necessary conditions for a Fra¨ıss´elimit to be spectrally universal. As an application, we prove that the computable atomless Boolean algebra is spectrally universal. Contents 1. Introduction1 1.1. Classical results about Fra¨ıss´elimits and background definitions4 2. Computable Ages5 3. Computable Fra¨ıss´elimits8 3.1. Computable properties of Fra¨ıss´elimits8 3.2. Existence of computable Fra¨ıss´elimits9 4. Examples 15 5. Upward closure of degree spectra of relations 18 6. Necessary conditions for spectral universality 20 6.1. Local finiteness 20 6.2. Finite realizability 21 7. A sufficient condition for spectral universality 22 7.1. The countable atomless Boolean algebra 23 References 24 1. Introduction Computable model theory studies the algorithmic complexity of countable structures, of their isomorphisms, and of relations on such structures. Since algorithmic properties often depend on data presentation, in computable model theory classically isomorphic structures can have different computability-theoretic properties. -
LINEAR ALGEBRA METHODS in COMBINATORICS László Babai
LINEAR ALGEBRA METHODS IN COMBINATORICS L´aszl´oBabai and P´eterFrankl Version 2.1∗ March 2020 ||||| ∗ Slight update of Version 2, 1992. ||||||||||||||||||||||| 1 c L´aszl´oBabai and P´eterFrankl. 1988, 1992, 2020. Preface Due perhaps to a recognition of the wide applicability of their elementary concepts and techniques, both combinatorics and linear algebra have gained increased representation in college mathematics curricula in recent decades. The combinatorial nature of the determinant expansion (and the related difficulty in teaching it) may hint at the plausibility of some link between the two areas. A more profound connection, the use of determinants in combinatorial enumeration goes back at least to the work of Kirchhoff in the middle of the 19th century on counting spanning trees in an electrical network. It is much less known, however, that quite apart from the theory of determinants, the elements of the theory of linear spaces has found striking applications to the theory of families of finite sets. With a mere knowledge of the concept of linear independence, unexpected connections can be made between algebra and combinatorics, thus greatly enhancing the impact of each subject on the student's perception of beauty and sense of coherence in mathematics. If these adjectives seem inflated, the reader is kindly invited to open the first chapter of the book, read the first page to the point where the first result is stated (\No more than 32 clubs can be formed in Oddtown"), and try to prove it before reading on. (The effect would, of course, be magnified if the title of this volume did not give away where to look for clues.) What we have said so far may suggest that the best place to present this material is a mathematics enhancement program for motivated high school students. -
Computational Learning Theory: New Models and Algorithms
Computational Learning Theory: New Models and Algorithms by Robert Hal Sloan S.M. EECS, Massachusetts Institute of Technology (1986) B.S. Mathematics, Yale University (1983) Submitted to the Department- of Electrical Engineering and Computer Science in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 1989 @ Robert Hal Sloan, 1989. All rights reserved The author hereby grants to MIT permission to reproduce and to distribute copies of this thesis document in whole or in part. Signature of Author Department of Electrical Engineering and Computer Science May 23, 1989 Certified by Ronald L. Rivest Professor of Computer Science Thesis Supervisor Accepted by Arthur C. Smith Chairman, Departmental Committee on Graduate Students Abstract In the past several years, there has been a surge of interest in computational learning theory-the formal (as opposed to empirical) study of learning algorithms. One major cause for this interest was the model of probably approximately correct learning, or pac learning, introduced by Valiant in 1984. This thesis begins by presenting a new learning algorithm for a particular problem within that model: learning submodules of the free Z-module Zk. We prove that this algorithm achieves probable approximate correctness, and indeed, that it is within a log log factor of optimal in a related, but more stringent model of learning, on-line mistake bounded learning. We then proceed to examine the influence of noisy data on pac learning algorithms in general. Previously it has been shown that it is possible to tolerate large amounts of random classification noise, but only a very small amount of a very malicious sort of noise. -
On the NP-Completeness of the Minimum Circuit Size Problem
On the NP-Completeness of the Minimum Circuit Size Problem John M. Hitchcock∗ A. Pavany Department of Computer Science Department of Computer Science University of Wyoming Iowa State University Abstract We study the Minimum Circuit Size Problem (MCSP): given the truth-table of a Boolean function f and a number k, does there exist a Boolean circuit of size at most k computing f? This is a fundamental NP problem that is not known to be NP-complete. Previous work has studied consequences of the NP-completeness of MCSP. We extend this work and consider whether MCSP may be complete for NP under more powerful reductions. We also show that NP-completeness of MCSP allows for amplification of circuit complexity. We show the following results. • If MCSP is NP-complete via many-one reductions, the following circuit complexity amplifi- Ω(1) cation result holds: If NP\co-NP requires 2n -size circuits, then ENP requires 2Ω(n)-size circuits. • If MCSP is NP-complete under truth-table reductions, then EXP 6= NP \ SIZE(2n ) for some > 0 and EXP 6= ZPP. This result extends to polylog Turing reductions. 1 Introduction Many natural NP problems are known to be NP-complete. Ladner's theorem [14] tells us that if P is different from NP, then there are NP-intermediate problems: problems that are in NP, not in P, but also not NP-complete. The examples arising out of Ladner's theorem come from diagonalization and are not natural. A canonical candidate example of a natural NP-intermediate problem is the Graph Isomorphism (GI) problem. -
Computational Science and Engineering
Computational Science and Engineering, PhD College of Engineering Graduate Coordinator: TBA Email: Phone: Department Chair: Marwan Bikdash Email: [email protected] Phone: 336-334-7437 The PhD in Computational Science and Engineering (CSE) is an interdisciplinary graduate program designed for students who seek to use advanced computational methods to solve large problems in diverse fields ranging from the basic sciences (physics, chemistry, mathematics, etc.) to sociology, biology, engineering, and economics. The mission of Computational Science and Engineering is to graduate professionals who (a) have expertise in developing novel computational methodologies and products, and/or (b) have extended their expertise in specific disciplines (in science, technology, engineering, and socioeconomics) with computational tools. The Ph.D. program is designed for students with graduate and undergraduate degrees in a variety of fields including engineering, chemistry, physics, mathematics, computer science, and economics who will be trained to develop problem-solving methodologies and computational tools for solving challenging problems. Research in Computational Science and Engineering includes: computational system theory, big data and computational statistics, high-performance computing and scientific visualization, multi-scale and multi-physics modeling, computational solid, fluid and nonlinear dynamics, computational geometry, fast and scalable algorithms, computational civil engineering, bioinformatics and computational biology, and computational physics. Additional Admission Requirements Master of Science or Engineering degree in Computational Science and Engineering (CSE) or in science, engineering, business, economics, technology or in a field allied to computational science or computational engineering field. GRE scores Program Outcomes: Students will demonstrate critical thinking and ability in conducting research in engineering, science and mathematics through computational modeling and simulations. -
31 Summary of Computability Theory
CS:4330 Theory of Computation Spring 2018 Computability Theory Summary Haniel Barbosa Readings for this lecture Chapters 3-5 and Section 6.2 of [Sipser 1996], 3rd edition. A hierachy of languages n m B Regular: a b n n B Deterministic Context-free: a b n n n 2n B Context-free: a b [ a b n n n B Turing decidable: a b c B Turing recognizable: ATM 1 / 12 Why TMs? B In 1900: Hilbert posed 23 “challenge problems” in Mathematics The 10th problem: Devise a process according to which it can be decided by a finite number of operations if a given polynomial has an integral root. It became necessary to have a formal definition of “algorithms” to define their expressivity. 2 / 12 Church-Turing Thesis B In 1936 Church and Turing independently defined “algorithm”: I λ-calculus I Turing machines B Intuitive notion of algorithms = Turing machine algorithms B “Any process which could be naturally called an effective procedure can be realized by a Turing machine” th B We now know: Hilbert’s 10 problem is undecidable! 3 / 12 Algorithm as Turing Machine Definition (Algorithm) An algorithm is a decider TM in the standard representation. B The input to a TM is always a string. B If we want an object other than a string as input, we must first represent that object as a string. B Strings can easily represent polynomials, graphs, grammars, automata, and any combination of these objects. 4 / 12 How to determine decidability / Turing-recognizability? B Decidable / Turing-recognizable: I Present a TM that decides (recognizes) the language I If A is mapping reducible to -
NP-Completeness Part I
NP-Completeness Part I Outline for Today ● Recap from Last Time ● Welcome back from break! Let's make sure we're all on the same page here. ● Polynomial-Time Reducibility ● Connecting problems together. ● NP-Completeness ● What are the hardest problems in NP? ● The Cook-Levin Theorem ● A concrete NP-complete problem. Recap from Last Time The Limits of Computability EQTM EQTM co-RE R RE LD LD ADD HALT ATM HALT ATM 0*1* The Limits of Efficient Computation P NP R P and NP Refresher ● The class P consists of all problems solvable in deterministic polynomial time. ● The class NP consists of all problems solvable in nondeterministic polynomial time. ● Equivalently, NP consists of all problems for which there is a deterministic, polynomial-time verifier for the problem. Reducibility Maximum Matching ● Given an undirected graph G, a matching in G is a set of edges such that no two edges share an endpoint. ● A maximum matching is a matching with the largest number of edges. AA maximummaximum matching.matching. Maximum Matching ● Jack Edmonds' paper “Paths, Trees, and Flowers” gives a polynomial-time algorithm for finding maximum matchings. ● (This is the same Edmonds as in “Cobham- Edmonds Thesis.) ● Using this fact, what other problems can we solve? Domino Tiling Domino Tiling Solving Domino Tiling Solving Domino Tiling Solving Domino Tiling Solving Domino Tiling Solving Domino Tiling Solving Domino Tiling Solving Domino Tiling Solving Domino Tiling The Setup ● To determine whether you can place at least k dominoes on a crossword grid, do the following: ● Convert the grid into a graph: each empty cell is a node, and any two adjacent empty cells have an edge between them. -
Computational Complexity Computational Complexity
In 1965, the year Juris Hartmanis became Chair Computational of the new CS Department at Cornell, he and his KLEENE HIERARCHY colleague Richard Stearns published the paper On : complexity the computational complexity of algorithms in the Transactions of the American Mathematical Society. RE CO-RE RECURSIVE The paper introduced a new fi eld and gave it its name. Immediately recognized as a fundamental advance, it attracted the best talent to the fi eld. This diagram Theoretical computer science was immediately EXPSPACE shows how the broadened from automata theory, formal languages, NEXPTIME fi eld believes and algorithms to include computational complexity. EXPTIME complexity classes look. It As Richard Karp said in his Turing Award lecture, PSPACE = IP : is known that P “All of us who read their paper could not fail P-HIERARCHY to realize that we now had a satisfactory formal : is different from ExpTime, but framework for pursuing the questions that Edmonds NP CO-NP had raised earlier in an intuitive fashion —questions P there is no proof about whether, for instance, the traveling salesman NLOG SPACE that NP ≠ P and problem is solvable in polynomial time.” LOG SPACE PSPACE ≠ P. Hartmanis and Stearns showed that computational equivalences and separations among complexity problems have an inherent complexity, which can be classes, fundamental and hard open problems, quantifi ed in terms of the number of steps needed on and unexpected connections to distant fi elds of a simple model of a computer, the multi-tape Turing study. An early example of the surprises that lurk machine. In a subsequent paper with Philip Lewis, in the structure of complexity classes is the Gap they proved analogous results for the number of Theorem, proved by Hartmanis’s student Allan tape cells used.