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On the Irrelevance of Transformational Grammar to Second Language Pedagogy
ON THE IRRELEVANCE OF TRANSFORMATIONAL GRAMMAR TO SECOND LANGUAGE PEDAGOGY John T. Lamendella The University of Michigan Many scholars view transformational grammar as an attempt to represent the structure of linguistic knowledge in the mind and seek to apply transformational descriptions of languages to the de- velopment of second language teaching materials. It will be claimed in this paper that it is a mistake to look to transformational gram- mar or any other theory of linguistic description to provide the theoretical basis for either second language pedagogy or a theory of language acquisition. One may well wish to describe the ab- stract or logical structure of a language by constructing a trans- formational grammar which generates the set of sentences identi- fied with that language. However, this attempt should not be con- fused with an attempt to understand the cognitive structures and processes involved in knowing or using a language. It is a cogni- tive theory of language within the field of psycholinguistics rather than a theory of linguistic description which should underlie lan- guage teaching materials. A great deal of effort has been expended in the attempt to demonstrate the potential contributions of the field of descriptive linguistics to the teaching of second languages and, since the theory of transformational grammar has become the dominant theory in the field of linguistics, it is not surprising that applied linguists have sought to apply transformational grammar to gain new in- sights into the teaching of second languages. It will be claimed in this paper that it is a mistake to look to transformational grammar or any other theory of linguistic description to provide the theoretical basis for either second language pedagogy or a theory of language acquisition. -
The Continuity of Additive and Convex Functions, Which Are Upper Bounded
THE CONTINUITY OF ADDITIVE AND CONVEX FUNCTIONS, WHICH ARE UPPER BOUNDED ON NON-FLAT CONTINUA IN Rn TARAS BANAKH, ELIZA JABLO NSKA,´ WOJCIECH JABLO NSKI´ Abstract. We prove that for a continuum K ⊂ Rn the sum K+n of n copies of K has non-empty interior in Rn if and only if K is not flat in the sense that the affine hull of K coincides with Rn. Moreover, if K is locally connected and each non-empty open subset of K is not flat, then for any (analytic) non-meager subset A ⊂ K the sum A+n of n copies of A is not meager in Rn (and then the sum A+2n of 2n copies of the analytic set A has non-empty interior in Rn and the set (A − A)+n is a neighborhood of zero in Rn). This implies that a mid-convex function f : D → R, defined on an open convex subset D ⊂ Rn is continuous if it is upper bounded on some non-flat continuum in D or on a non-meager analytic subset of a locally connected nowhere flat subset of D. Let X be a linear topological space over the field of real numbers. A function f : X → R is called additive if f(x + y)= f(x)+ f(y) for all x, y ∈ X. R x+y f(x)+f(y) A function f : D → defined on a convex subset D ⊂ X is called mid-convex if f 2 ≤ 2 for all x, y ∈ D. Many classical results concerning additive or mid-convex functions state that the boundedness of such functions on “sufficiently large” sets implies their continuity. -
Math 501. Homework 2 September 15, 2009 ¶ 1. Prove Or
Math 501. Homework 2 September 15, 2009 ¶ 1. Prove or provide a counterexample: (a) If A ⊂ B, then A ⊂ B. (b) A ∪ B = A ∪ B (c) A ∩ B = A ∩ B S S (d) i∈I Ai = i∈I Ai T T (e) i∈I Ai = i∈I Ai Solution. (a) True. (b) True. Let x be in A ∪ B. Then x is in A or in B, or in both. If x is in A, then B(x, r) ∩ A , ∅ for all r > 0, and so B(x, r) ∩ (A ∪ B) , ∅ for all r > 0; that is, x is in A ∪ B. For the reverse containment, note that A ∪ B is a closed set that contains A ∪ B, there fore, it must contain the closure of A ∪ B. (c) False. Take A = (0, 1), B = (1, 2) in R. (d) False. Take An = [1/n, 1 − 1/n], n = 2, 3, ··· , in R. (e) False. ¶ 2. Let Y be a subset of a metric space X. Prove that for any subset S of Y, the closure of S in Y coincides with S ∩ Y, where S is the closure of S in X. ¶ 3. (a) If x1, x2, x3, ··· and y1, y2, y3, ··· both converge to x, then the sequence x1, y1, x2, y2, x3, y3, ··· also converges to x. (b) If x1, x2, x3, ··· converges to x and σ : N → N is a bijection, then xσ(1), xσ(2), xσ(3), ··· also converges to x. (c) If {xn} is a sequence that does not converge to y, then there is an open ball B(y, r) and a subsequence of {xn} outside B(y, r). -
Baire Category Theorem
Baire Category Theorem Alana Liteanu June 2, 2014 Abstract The notion of category stems from countability. The subsets of metric spaces are divided into two categories: first category and second category. Subsets of the first category can be thought of as small, and subsets of category two could be thought of as large, since it is usual that asset of the first category is a subset of some second category set; the verse inclusion never holds. Recall that a metric space is defined as a set with a distance function. Because this is the sole requirement on the set, the notion of category is versatile, and can be applied to various metric spaces, as is observed in Euclidian spaces, function spaces and sequence spaces. However, the Baire category theorem is used as a method of proving existence [1]. Contents 1 Definitions 1 2 A Proof of the Baire Category Theorem 3 3 The Versatility of the Baire Category Theorem 5 4 The Baire Category Theorem in the Metric Space 10 5 References 11 1 Definitions Definition 1.1: Limit Point.If A is a subset of X, then x 2 X is a limit point of X if each neighborhood of x contains a point of A distinct from x. [6] Definition 1.2: Dense Set. As with metric spaces, a subset D of a topological space X is dense in A if A ⊂ D¯. D is dense in A. A set D is dense if and only if there is some 1 point of D in each nonempty open set of X. -
The Development of Mathematical Logic from Russell to Tarski: 1900–1935
The Development of Mathematical Logic from Russell to Tarski: 1900–1935 Paolo Mancosu Richard Zach Calixto Badesa The Development of Mathematical Logic from Russell to Tarski: 1900–1935 Paolo Mancosu (University of California, Berkeley) Richard Zach (University of Calgary) Calixto Badesa (Universitat de Barcelona) Final Draft—May 2004 To appear in: Leila Haaparanta, ed., The Development of Modern Logic. New York and Oxford: Oxford University Press, 2004 Contents Contents i Introduction 1 1 Itinerary I: Metatheoretical Properties of Axiomatic Systems 3 1.1 Introduction . 3 1.2 Peano’s school on the logical structure of theories . 4 1.3 Hilbert on axiomatization . 8 1.4 Completeness and categoricity in the work of Veblen and Huntington . 10 1.5 Truth in a structure . 12 2 Itinerary II: Bertrand Russell’s Mathematical Logic 15 2.1 From the Paris congress to the Principles of Mathematics 1900–1903 . 15 2.2 Russell and Poincar´e on predicativity . 19 2.3 On Denoting . 21 2.4 Russell’s ramified type theory . 22 2.5 The logic of Principia ......................... 25 2.6 Further developments . 26 3 Itinerary III: Zermelo’s Axiomatization of Set Theory and Re- lated Foundational Issues 29 3.1 The debate on the axiom of choice . 29 3.2 Zermelo’s axiomatization of set theory . 32 3.3 The discussion on the notion of “definit” . 35 3.4 Metatheoretical studies of Zermelo’s axiomatization . 38 4 Itinerary IV: The Theory of Relatives and Lowenheim’s¨ Theorem 41 4.1 Theory of relatives and model theory . 41 4.2 The logic of relatives . -
Real Analysis, Math 821. Instructor: Dmitry Ryabogin Assignment
Real Analysis, Math 821. Instructor: Dmitry Ryabogin Assignment IV. 1. Problem 1. Definition 1. A set M ⊂ R is called closed if it coincides with its closure. In other words, M ⊂ R is closed, if it contains all of its limit points. Definition 2. A set A ⊂ R is called open if there is a closed set M ⊂ R such that A = R n M. In other words, A is open if all of its points are inner points, (a point x is called the inner point of a set A, if there exists > 0, such that the -neighbourhood U(x) of x, is contained in A, U(x) ⊂ A). Prove that any open set on the real line is a finite or infinite union of disjoint open intervals. (The sets (−∞; 1), (α, 1), (−∞; β) are intervals for us). Hint. Let G be open on R. Introduce in G the equivalence relationship, by saying that x ∼ y if there exists an interval (α, β), such that x; y 2 (α, β) ⊂ G. a) Prove at first that this is indeed the equivalence relationship, i. e., that x ∼ x, x ∼ y implies y ∼ x, and x ∼ y, y ∼ z imply x ∼ z. Conclude that G can be written as a disjoint union G = [τ2iIτ of \classes" of points Iτ , Iτ = fx 2 G : x ∼ τg, i is the set of different indices, i.e. τ 2 i if Iτ \ Ix = ?, 8x 2 G. b) Prove that each Iτ is an open interval. c) Show that there are at most countably many Iτ (the set i is countable). -
Russell and Philip Jourdain a Study of Their Relationship
Russell and Philip Jourdain a study of their relationship One of the frustrations of Russellian scholarship is that there is often no trace among his papers of the letters he wrote Defore 1952 to his many correspondents. One of the most important missions of the Bertrand Russell Archives is to find as many of these letters as possible; for whenever some are found, new insights and detail s emerge. Without denying the central importance of the papers purchased from Russell in 1968, the most exciting development may be the growth of its section of recent acquisitions from 'other sources. A collection of letters of this type which is of unique importance is the surviving correspondence between Russell and the mathematician and historian of mathematics Philip Jourdain (1879-1919}. Jourdain suffered throughout his life from FriedriCh's ataxia, a crippling palsey which made writing extremely difficult for him. l Nevertheless he successfully pursued a career in research and scholarship. Indeed, all his brothers and sisters were remarkable in one way or another. For example, his eldest sister Eleanor was Vice-Principal of st. Hugh's College, Oxford (and Russell knew her quite we].l in the years when he lived in the city), and in 1911 she and her Principal Annie Moberley caused a sensation when they published pseudonymously a book claiming that in 1901 they had seen Marie Antoinette and members of her court during a visit to Versailles. 2 Philip had strong views, especially in favour of foundational studies in mathematics and against the church, and later in his life he shared with Russell strong pacifist inclinations. -
Arxiv:1809.06453V3 [Math.CA]
NO FUNCTIONS CONTINUOUS ONLY AT POINTS IN A COUNTABLE DENSE SET CESAR E. SILVA AND YUXIN WU Abstract. We give a short proof that if a function is continuous on a count- able dense set, then it is continuous on an uncountable set. This is done for functions defined on nonempty complete metric spaces without isolated points, and the argument only uses that Cauchy sequences converge. We discuss how this theorem is a direct consequence of the Baire category theorem, and also discuss Volterra’s theorem and the history of this problem. We give a sim- ple example, for each complete metric space without isolated points and each countable subset, of a real-valued function that is discontinuous only on that subset. 1. Introduction. A function on the real numbers that is continuous only at 0 is given by f(x) = xD(x), where D(x) is Dirichlet’s function (i.e., the indicator function of the set of rational numbers). From this one can construct examples of functions continuous at only finitely many points, or only at integer points. It is also possible to construct a function that is continuous only on the set of irrationals; a well-known example is Thomae’s function, also called the generalized Dirichlet function—and see also the example at the end. The question arrises whether there is a function defined on the real numbers that is continuous only on the set of ra- tional numbers (i.e., continuous at each rational number and discontinuous at each irrational), and the answer has long been known to be no. -
Arxiv:1603.05121V3 [Math.GM] 31 Oct 2016 Definition of Set Derived Efc (I.E
SOME EXISTENCE RESULTS ON CANTOR SETS Borys Alvarez-Samaniego´ N´ucleo de Investigadores Cient´ıficos Facultad de Ingenier´ıa, Ciencias F´ısicas y Matem´atica Universidad Central del Ecuador (UCE) Quito, Ecuador Wilson P. Alvarez-Samaniego´ N´ucleo de Investigadores Cient´ıficos Facultad de Ingenier´ıa, Ciencias F´ısicas y Matem´atica Universidad Central del Ecuador (UCE) Quito, Ecuador Jonathan Ortiz-Castro Facultad de Ciencias Escuela Polit´ecnica Nacional (EPN) Quito, Ecuador Abstract. The existence of two different Cantor sets, one of them contained in the set of Liouville numbers and the other one inside the set of Diophan- tine numbers, is proved. Finally, a necessary and sufficient condition for the existence of a Cantor set contained in a subset of the real line is given. MSC: 54A05; 54B05 Keywords: Cantor set; Liouville numbers; Diophantine numbers. arXiv:1603.05121v3 [math.GM] 31 Oct 2016 1. Introduction First, we will introduce some basic topological concepts. Definition 1.1. A nowhere dense set X in a topological space is a set whose closure has empty interior, i.e. int(X)= ∅. Definition 1.2. A nonempty set C ⊂ R is a Cantor set if C is nowhere dense and perfect (i.e. C = C′, where C′ := {p ∈ R; p is an accumulation point of C} is the derived set of C). Definition 1.3. A condensation point t of a subset A of a topological space, is any point t, such that every open neighborhood of t contains uncountably many points of A. Date: October 31, 2016. 1 2 B. ALVAREZ-SAMANIEGO,´ W. -
Performance-Compatible Competence Grammar
Performance-Compatible Competence Grammar Ivan A. Sag and Thomas Wasow Stanford University ¡ sag,wasow ¢ @csli.stanford.edu 1 Competence and Performance Half a century ago, Noam Chomsky introduced the field of linguistics to new mathematical tools drawn largely from recursive function theory. These were exciting tools that imparted mathematical precision, perhaps for the first time in the history of Linguistics, to the enterprise of grammar construction. The cornerstone of Chomsky's new theoretical edifice, was the grammatical transformation, an analytic device which led to new insights about a vast array of empirical phenomena left unanalyzed by previous linguistic traditions. As the theory of transformations developed, so did Chomsky's conception of linguistic theory. Transformational grammar was accorded the status of a theory of idealized linguis- tic knowledge – linguistic competence, to be distinguished from the more general study of language use (including the unconscious mental processes involved in producing and compre- hending utterances), termed linguistic performance. The relation between these two notions, as Chomsky (1965:10) emphasized, is that “... investigation of performance will proceed only so far as understanding of underlying competence permits.” For all their initial descriptive success, however, linguistic transformations have proven rather intransigent. Early psycholinguistic studies based on transformational grammar sought to show a correlation between the psychological complexity of sentences and the number of transformations involved in their derivations. The initial experiments provided enough support for this `derivational theory of complexity' (DTC) that Chomsky (1968) wrote “The results show a remarkable correlation of the amount of memory and number of transformations”. But this optimism was short-lived. -
Philip Jourdain, Historiador De Las Matematicas
NOTAS PHILIP JOURDAIN, HISTORIADOR DE LAS MATEMATICAS ALEJANDRO R. GARCIADIEGO Facultad de Ciencias (México) RESUMEN ABSTRACT Philip Jourdain es conocido por Philip Jourdain is known by los historiadores de las matemáticas, historians of mathematics, among entre otras razones, a través de su other factors, by his correspondence correspondencia con algunos de los with some of the most famous matemáticos más famosos de su mathematicians of his days (e.g., tiempo (e.g., Georg Cantor (1845- Georg Cantor (1845-1918) and 1918) y Bertrand Russell (1872- Bertrand Russell (1872-1970) among 1970), entre otros); por sus artículos others); by his works on the history sobre la historia y filosofía de las and philosophy of mathematics; by his matemáticas; por sus artículos de publications on the theory of sets investigación en torno a la teoría de (especially, on the arithmetic of conjuntos (especialmente, en la transfinite cardinal and ordinal aritmética de los n ŭmeros cardinales y numbers); and, by his translation of ordinales transfinitos); y, por la Cantor's Beitráge... (1895-1897). The traducción del Beitráge... (1895-1897) goal of this essay is to discuss the de Cantor. En este ensayo discutiré la relation between his views of the relación entre sus puntos de vista nature of mathematics and his sobre la naturaleza de las matemáticas conception of the history of y su concepción de la historia de las mathematics which, apparently and at mismas que, aparentemente y a primera first sight, are inconsistent. vista, son contradictorias. 194 NOTAS LLULL 22 1. Introducción Philip Eduard Bertrand Jourdain, el más joven de los hijos del Reverendo F. -
Hugh Maccoll After One Hundred Years
Philosophia Scientiæ Travaux d'histoire et de philosophie des sciences 15-1 | 2011 Hugh MacColl after One Hundred Years Amirouche Moktefi and Stephen Read (dir.) Electronic version URL: http://journals.openedition.org/philosophiascientiae/351 DOI: 10.4000/philosophiascientiae.351 ISSN: 1775-4283 Publisher Éditions Kimé Printed version Date of publication: 1 April 2011 ISBN: 978-2-84174-551-7 ISSN: 1281-2463 Electronic reference Amirouche Moktefi and Stephen Read (dir.), Philosophia Scientiæ, 15-1 | 2011, “Hugh MacColl after One Hundred Years” [Online], Online since 01 April 2011, connection on 15 January 2021. URL: http:// journals.openedition.org/philosophiascientiae/351; DOI: https://doi.org/10.4000/philosophiascientiae. 351 This text was automatically generated on 15 January 2021. Tous droits réservés Preface Amirouche Moktefi LHSP, Archives H. Poincaré (UMR 7117), Nancy-Université & IRIST (EA 3424), Université de Strasbourg, France Stephen Read Department of Logic and Metaphysics, University of St. Andrews, Scotland “It all turns upon that little word if, Mr. Burton.” [MacColl 1891, 955] This volume is devoted to the life and work of Hugh MacColl (1837- 1909), the Scottish mathematician, philosopher and novelist. Although MacColl is nowadays remembered mainly for his contributions to the science of logic, his work covers many other domains and witnesses the richness and variety of his intellectual interests. MacColl’s early writings (from 1861 onwards) were devoted to mathematics, notably geometry, algebra and the theory of probabilities. In the late 1870s and early 1880s, he published several papers on logic that brought him to the attention of his contemporaries. In these writings, he expressed his preference for propositional calculus instead of the term/class approach, widespread in his day.