Mathematics

In contemporary mathematics, a Colombeau algebra of Colombeau generalized functions is an algebra of a certain kind containing the space of Schwartz distributions. While in classical distribution theory a general multiplication of distributions is not possible, Colombeau algebras provide a rigorous framework for this. Remark 1.1.1.Such a multiplication of distributions has been a long time mistakenly believed to be impossible because of Schwartz’ impossibility result, which basically states that there cannot be a differential algebra containing the space of distributions and (...) preserving the product of continuous functions. However, if one only wants to preserve the product of smooth functions instead such a construction becomes possible, as demonstrated first by J.F.Colombeau [1],[2]. As a mathematical tool, Colombeau algebras can be said to combine a treatment of singularities, differentiation and nonlinear operations in one framework, lifting the limitations of distribution theory. These algebras have found numerous applications in the fields of partial differential equations, geophysics, microlocal analysis and general relativity so far. (shrink)

In the paper it is demonstrated that Bell's theorem is unproveable.

CAT4 is proposed as a general method for representing information, enabling a powerful programming method for large-scale information systems. It enables generalised machine learning, software automation and novel AI capabilities. It is based on a special type of relation called CAT4, which is interpreted to provide a semantic representation. This is Part 2 of a five-part introduction. The focus here is on defining key mathematical properties of CAT2, identifying the topology and defining essential functions over a coordinate system. The analysis (...) is from first principles. This develops on from the axioms introduced in Part 1. The interpretation of fact networks is introduced in Part 3, and the full application to semantic theory comes in Part 4, where we introduce general functions, including the language interpretation or linguistic functions. In Part 5, we turn to software design considerations, to show how files, indexes, functions and screens can be defined to implement a CAT4 system efficiently. (shrink)

I have been working for a long time about basic laws which direct existence, and some mathematical problems which are waited for a solution. I can count myself lucky, that I could make some important inferences during this time, and I published them in a few papers partially as some propositions. This work aimed to explain and discuss these inferences all together by relating them one another by some extra additions, corrections and explanations being physical phenomena are prior. There are (...) many motivation instruments for exact physical inferences. (shrink)

Long Range and short range, guns and violence, everyday life in cities and streets, between social and group identity and faith and religious belief, the vision to the "things of the world that cannot be seen" (Heróis do Mar).

That the state-of-affairs of cognitive science is not good is brought into figural salience in "What happened to cognitive science?" (Núñez et al., 2019). We extend their objective description of 'what's wrong' to a prescription of 'how to correct'. Cognitive science, in its quest to elucidate 'how we know', embraces a long list of subjects, while ignoring Mathematics (Fig. 1a, Núñez et al., 2019). Mathematics is known for making the unknown to be known (cf. solving for unknowns). This acknowledgement naturally (...) raises the question: does mathematical knowing inform knowing in general? Here we show that drawing parallels to mathematical knowing can facilitate the advancement of cognitive science (Lawvere, 1994). (shrink)

Mind, according to cognitive neuroscience, is a set of brain functions. But, unlike sets, our minds are cohesive. Moreover, unlike the structureless elements of sets, the contents of our minds are structured. Mutual relations between the mental contents endow the mind its structure. Here we characterize the structural essence and the logical form of the mind by focusing on thinking. Examination of the relations between concepts, propositions, and syllogisms involved in thinking revealed the reflexive graph structure of the conceptual mind. (...) Objective logic of the conceptual mind is calculated from its structure. Noteworthy features of the logic of conceptual mind are: degrees of truth, varieties of negation, admission of contradiction, and the failure of a de Morgan's law. Furthermore, cohesion of the conceptual mind follows from its reflexive graph structure. Our characterization of the structure and logic of mind constitutes a substantial refinement of the contemporary cognitive neuroscientific conceptualization of the mind as a set. (shrink)

Neuroscientific discourse on consciousness often resorts to "collection of elements", notwithstanding the Gestalt demonstrations against representing conscious experience as a collection of sensory elements. Here I show that defining conscious experience as an object of the category of conscious experiences, instead of as cohesion-less set of structure-less elements, provides the conceptual repertoire—basic shapes, figures, and incidence relations—needed to reason about the essence of conscious experiences and the essence-preserving transformations of conscious experiences. Viewed in light of the category of conscious experiences, (...) designers of user experience—in designing pre-conceptualized user experiences—are well situated to contribute to the development of the science of consciousness. (shrink)

Math literacy is miniscule compared to the near universal language literacy of mother tongues. Our search for the root cause of this undesirable human condition led us to: Grammar (or the abstract essence) of a language. Language learning begins with grammar, unless the language happens to be mathematics, which is unique in not even considering including the grammar (abstract general/theory) of mathematics in the mathematical pedagogy. Here we make a case for introducing the abstract essence of mathematics--Conceptual Mathematics--in high school (...) math curriculum. Recognizing that the singular purpose of education is to nurture the universal yearning for understanding, we show how a nurturing pedagogy naturally resolves the "learning crisis", with the solution manifesting as human development. Furthermore, the nurturing pedagogy that we advocate invariably results in the culture of research excellence. (shrink)

In this paper, I define and study an abstract algebraic structure, the dimensive algebra, which embodies the most general features of the algebra of dimensional physical quantities. I prove some elementary results about dimensive algebras and suggest some directions for future work.

The history of science is polarized by debates over Plato and Aristotle’s holism versus the atomism of Democritus and others. This includes the complementarity of continuous and discrete, one and the many, waves and particles, and analog or digital views of reality. The three-fold method of the Pythagorean paradigm of unity, duality, and harmony enables the calculation of fundamental physical constants required by the forces of nature in the formation of matter; thereby demonstrating Plato’s archetypal viewpoint.

This came into existence when one day (10 -12 years back), all of a sudden I draw a line and divided the line into same segment and draw one more line above the previous line and mark the points on the both lines and magically I got a triangle (while attach all the points with each other), with at point 1 no of points 1 at 2 no of points 3 and at 3 no of points 5. Now an idea (...) born into my mind while I should not expand it more and I got Amazing Result which is in front of All Mathematics Lovers. (shrink)

Motivation -/- God is great, whatever (Air, Water, Earth, Fire & Space) we have it is just because of a Power, which governs the whole universe and more than this Power, it has created human beings, and what we have got or did not get yet, trying to get. The Method, The Principle, The Knowledge or more by which we get or prove in front of World People, basically it is called Science, who GET it, are called Scientists, Mathematicians, Inventors (...) etc i.e. we all breath we all know but in ancient time we don’t know what we breath as the time passes away one man’s curiosity bring out the name of gas which we breathe i.e. Oxygen. There are lot examples or more yet to come. -/- In this regard my little contribution in the field of Mathematics, it starts from my early childhood I used to play with numbers. After a lot of times devoted on numbers one day while squaring 11, 12, 13 so on I found that there is an amazing symmetry of 2 & it’s great. (shrink)

A well-ordered society faces a crisis whenever a sufficient number of noncompliers enter into the political system. This has the potential to destabilize liberal democratic political order. This article provides a formal analysis of two competing solutions to the problem of political stability offered in the public reason liberalism literature—namely, using public reason or using convergence discourse to restore liberal democratic political order in the well-ordered society. The formal analyses offered in this article show that using public reason fails completely, (...) and using convergent discourse, although doing better, has its own critical limitations that have not been previously recognized properly. (shrink)

The goal of this paper is to explain the nature of philosophy as a distinct science with its own subject-matter. This is achieved through a comparative analysis of mathematical and philosophical knowledge that reveals a profound similarity between mathematics and philosophy as mutually complementary sciences exploring the field of abstract entities that can be comprehended only by purely a priori theoretical inquiry. By considering this complementarity, a general definition of philosophy can be obtained by dualizing the traditional Aristotelian definition of (...) mathematics as the “science of quantity”. Philosophy should thus be interpreted as an a priori science of the pure qualitative attributes of being. (shrink)

Although the idiom “genesis and structure” is usually associated with the rise of structuralism in the late 1950s and early 1960s, the two notions are arguably among the most persistent methods in the history of modern philosophy. This article outlines the emergence of “genetic epistemology” in the seventeenth century, when the seemingly antithetical character of the conceptual pair was reworked into a productive epistemological theory, especially in Descartes, Hobbes, Spinoza, and Leibniz, who increasingly used diachronic (genetic) narratives to explain the (...) synchronic (structural) features in their theories. Against Cassirer, I argue that it was Descartes rather than Hobbes who first presented structural issues genetically. In Descartes’ natural philosophy, his frequent claims that showing how a thing is produced reveals its true nature foreshadow precisely what Hobbes and Isaac Barrow later describe as causal definitions of geometric figures, in which the process of ideal generation by motion is what constitutes the very essence of a figure. I link this method to the historicizing discourse on origins in the Enlightenment and conclude by suggesting that there is a trace of Platonic idealism in genetic epistemology. (shrink)

By introducing and extending description logic (DLs) and growing up their application in knowledge representation and especially in OWLs and semantic web scope, many shortcomings and bugs were identified that weren’t resolvable in classical DLs and so logicians and computer scientists intended to non-classical and non-monotonic reasoning tools. In this paper, I discuses about abduction problem solvers, and by introducing A-Box abduction in description logics (DLs), such as ALC, discuss about decidability and complexity in different introduced algorithms, and report shortly (...) our team’s advantages in developing and implementation of ΑBox abduction in DLs. (shrink)

In this article, I consider the positive logic of Boolean groups (i.e. Abelian groups where every non-identity element has order 2), where these are taken as frames for an operational semantics à la Urquhart. I call this logic BG. It is shown that the logic over the smallest nontrivial Boolean group, taken as a frame, is identical to the positive fragment of a quasi-relevance logic that was developed by Robles and Méndez (an extension of this result where negation is included (...) is also discussed). It is proved that BG satisfies the variable sharing property and is Halldén complete, while failing to satisfy the disjunction property. Sound and complete subscripted tableaux are presented for BG. An axiomatization (in the positive language extended with fusion) is presented, which is sound with respect to BG and, with respect to a related ternary relational semantics, complete; the problem of identifying a complete axiomatization for BG itself is left open. Connections between BG and the quasi-relevance logic KR are also discussed. (shrink)

Całość rozpoczyna teoretyczny rozdział matematyczno-statystyczny. Jego istota i charakter jest odmienny, od pozostałych dziewięciu rozdziałów praktyczno-specjalistycznych. Prezentuje on aparat matematyczno-statystyczny niezbędny do zrozumienia treści kolejnych kierunkowych już rozdziałów monografii. Treści merytoryczne tego rozdziału nie są zaprezentowane w formie systematycznego wykładu, czy prezentacji, ale przedstawiają jedynie sygnalnie i syntetycznie pojęcia, definicje, twierdzenia oraz zasady i metody, które stanowią fundament ich zastosowań w naukach ekonomicznych, finansach oraz informatyce. Rozdziały: od drugiego do dziesiątego są kierunkowymi rozdziałami specjalistycznymi i prezentują różne kierunki praktycznych zastosowań (...) metod matematycznych i statystycznych, czyli ilościowych. Rozdziały: drugi i trzeci dotyczą zarządzania finansami. Przy czym pierwszy z nich dotyczy naliczania odsetek w banku od dyspozytorów kredytów i obligacji. Kolejny zaś traktuje o metodach oceny ekonomicznej efektywności projektów inwestycyjnych i produkcyjnych oraz zawiera analizę wrażliwości wybranych wskaźników finansowych na zmiany czynników je tworzących. Rozdział czwarty prezentuje podstawowe informacje i zasady korzystania z arkusza kalkulacyjnego na przykładzie programu MS Excel wraz z omówieniem wybranych funkcji finansowych. W rozdziale piątym omówione są wybrane narzędzia wspomagające przetwarzanie danych informacji, jakimi są systemy SAS wykorzystywane przede wszystkim w interakcjach gospodarczych oraz w procesie dydaktycznym na uczelniach wyższych. Modele zachowań konsumenta, idea aproksymacji oraz wybrane mikroekonomiczne funkcje popytu zostały – wraz z przykładami – omówione w rozdziale szóstym. W rozdziale siódmym czytelnik znajdzie opis działań podejmowanych przez firmę w celu optymalizacji jej finansowego i gospodarczego funkcjonowania w okresie niepewności rynkowej na przykładzie pandemii COVID 19 i konkretnego przdsiębiorstwa. Dwa kolejne rozdziały: ósmy i dziewiąty są ze sobą ściśle zintegrowane. Oba one dotyczą niedookreślonych układów równań liniowych. Pierwszy z nich – o charakterze teoretycznym – poświęcony jest rozważaniom dotyczącym wykorzystywaniu rachunku macierzowego do rozwiązywania niedookreślonych układów równań liniowych. Kolejny zaś przedstawia praktyczne zastosowanie teoretycznych kwestii rozdziału poprzedniego do określenia wyceny wartości rynkowej nieruchomości. Monografię kończy rozdział dziesiąty dotyczący wybranych narzędzi wspierających proces sprzedaży usług finansowych wraz z prezentacją prognoz służących zminimalizowaniu ryzyka i błędów w procesie planowania sprzedaży w organizacji. W większości rozdziałów zawarte są rozwiązane przykładowo zadania z wyczerpującym komentarzem objaśniającym. Niniejsza monografia składa się z dziesięciu rozdziałów, jednak – zdaniem autorów – tematyka zastosowania metod ilościowych nie została w niej wyczerpana. Toteż planowana jest kolejna część tej publikacji zawierająca kontynuację podjętego i aktualnie rozpoczętego tematu. (shrink)

In abstract algebraic logic, many systems, such as those paraconsistent logics taking inspiration from da Costa's hierarchy, are not algebraizable by even the broadest standard methodologies, as that of Blok and Pigozzi. However, these logics can be semantically characterized by means of non-deterministic algebraic structures such as Nmatrices, RNmatrices and swap structures. These structures are based on multialgebras, which generalize algebras by allowing the result of an operation to assume a non-empty set of values. This leads to an interest in (...) exploring the foundations of multialgebras applied to the study of logic systems. -/- It is well known from universal algebra that, for every signature Sigma, there exist algebras over Sigma which are absolutely free, meaning that they do not satisfy any identities or, alternatively, satisfy the universal mapping property for the class of Sigma-algebras. Furthermore, once we fix a cardinality of the generating set, they are, up to isomorphisms, unique, and equal to algebras of terms (or propositional formulas, in the context of logic). Equivalently, the forgetful functor, from the category of Sigma-algebras to Set, has a left adjoint. This result does not extend to multialgebras. Not only multialgebras satisfying the universal mapping property do not exist, but the forgetful functor U, from the category of Sigma-multialgebras to Set, does not have a left adjoint. -/- In this paper we generalize, in a natural way, algebras of terms to multialgebras of terms, whose family of submultialgebras enjoys many properties of the former. One example is that, to every pair consisting of a function, from a submultialgebra of a multialgebra of terms to another multialgebra, and a collection of choices (which selects how a homomorphism approaches indeterminacies), there corresponds a unique homomorphism, what resembles the universal mapping property. Another example is that the multialgebras of terms are generated by a set that may be viewed as a strong basis, which we call the ground of the multialgebra. Submultialgebras of multialgebras of terms are what we call weakly free multialgebras. Finally, with these definitions at hand, we offer a simple proof that multialgebras with the universal mapping property for the class of all multialgebras do not exist and that U does not have a left adjoint. (shrink)

La siguiente ponencia-taller tiene por finalidad explicar cómo podría aplicarse el Método de George Polya para resolver problemas (matemáticos) en el contexto de la Lógica Matemática, especialmente en la lógica Matemática elemental (la lógica de primer orden con identidad). Es una propuesta pedagógica experimental (además de las ya existentes) que tal vez pueda ser útil para la enseñanza de la lógica matemática en ciencias o en humanidades. Dicha ponencia se presentó (vía web) con motivo de la celebración del Día Mundial (...) de Lógica 2022 en dos ocasiones: En la Universidad Central de Venezuela (Venezuela) y en la Universidad Mayor de San Andrés (Logic & Analytics Group - La Paz y La Sociedad Científica de Filosofía de la UMSA, Bolivia). Es un proyecto pedagógico en construcción. (shrink)

The New Collection is a peer-reviewed interdisciplinary academic journal published by the Middle Common Room of New College, University of Oxford.

This paper presents a methodology for exploring systematic co-variation of vowels using Principal Component Analysis (PCA). As a case study, we examine and build on Brand et al.'s (2021) study of systematic co-variation amongst the monophthongs of New Zealand English (NZE) across speakers born over a 118-year time period. We present PCA as a methodology, with information aimed at readers who may themselves want to use it in a related context. We consider tests for the appropriateness of PCA, how to (...) select Principal Components, and how to interpret them once they have been found. At each stage, we provide code in the R programing language to enable readers to both follow our analysis and apply the same methods to their own data. (shrink)

3rd ed, 2021. A circumscription of the classical theory of computation building up from the Chomsky hierarchy. With the usual topics in formal language and automata theory.

Book Review Mathematics of casino carnival games by Mark Bollman, New York: CRC Press 2021, 318 pp., GBP 48.99 (hardback), ISBN 9780367348656.

Book Review Luck, logic, and white lies: the mathematics of games, second edition by Jörg Bewersdorff, New York, Taylor & Francis, CRC Press, 2021, 568 pp., GBP 42.99 (paperback), ISBN 9780367548414, Number of chapters 51.

This is the first in a series of math books intended for those who have completed at least secondary school mathematics and have acquired 1) certain calculating skills, and 2) dissatisfaction with their understanding of what they are calculating. We will start our journey with numbers. Numbers are the oldest mathematical idea, but still also the most important one. We will go through the basics of numbers in a way that will give you the confidence to really understand numbers and (...) really know how to apply them. You will also learn all the essential elements of mathematics through the example of the world of numbers. The example of numbers will be used to illustrate what mathematical objects are and how they are applied, and what mathematical tools we use in their description and application. (shrink)

The symbolism of nature as a book in which one reads is of ancient origin. This study focuses on the question of its mathematical and theological language in the biblical context and on the background of changes in natural philosophy, especially in the Renaissance period. The biblical context is associated with the paradigm shift in the Renaissance period, because all the researched authors addressed the questions of meaning and methods of research of nature in connection with the hermeneutics of biblical (...) texts. The change in attitude towards the method and results of nature research is connected with two concepts of the relationship of mathematics to the real world. As this world is considered to be created by God, the relationship of mathematics and matter is linked to the question of God's relationship to mathematics. In relation to nature, it was initially significantly limited to geometry, largely under the influence of Euclid and Pythagoras. In the Renaissance period, the preconditions for analytical geometry and infinitesimal calculus were already being created. Thanks to them, Newton was able to build a new physics that combined ancient and medieval approaches to astronomy and terrestrial nature, originally diametrically different, into one whole. (shrink)

For an arbitrary forcing class Γ, the Γ-fragment of Todorčević’s strong reflection principle SRPis isolated in such a way that the forcing axiom for Γ implies the Γ-fragment of SRP, the sta...

La presente investigación tiene como propósito general asumir un posicionamiento filosófico en clave histórico-social y de tipo anti-relativista para analizar el desarrollo histórico de la matemática, el cual aplicaremos a un caso en particular: la matemática del antiguo Egipto. Para ello se discutirán y criticarán, en primera instancia, determinadas posiciones filosóficas afines al cuasi-empirismo en matemática que, siendo relativistas, permitirán delinear nuestro propio posicionamiento en contraste: la existencia de una «matemática situada». Esta categoría filosófica tendrá como sustento teórico la noción (...) de conocimiento situado. Además, las implicaciones de esta son, según sostenemos, tanto filosóficas como historiográficas, ya que servirá para analizar las características del corpus de problemas matemáticos egipcios registrados en los diversos papiros matemáticos. En particular, haremos referencia a las expresiones lingüísticas egipcias para denotar las diversas operaciones aritméticas y el carácter algorítmico de los problemas, así como también la cuestión epistemológica de la empiria y cómo la perspectiva situada permite superar la dicotomía entre una matemática pura y otra aplicada, que consideramos no es ubicua para abordar la interpretación de la práctica matemática del antiguo país del Nilo. Palabras clave: Filosofía de la matemática, Anti-relativismo, Matemática situada, Extrañeza del pasado, Matemática egipcia. (shrink)

We study the notion of ????-MAD families where ???? is a Borel ideal on ω. We show that if ???? is any finite or countably iterated Fubini product of the ideal of finite sets Fin, then there are no analytic...

Astrobiology is premised on the idea that life beyond Earth can exist. Yet, everything known about life is derivative from life on Earth. To understand life beyond Earth, then, requires a definition of life that is abstracted beyond a particular geophysical context. To do this requires a formal understanding of the physical mechanisms by which matter is animated into life. At current, such descriptions are completely lacking for the emergence of life, but do exist for the emergence of consciousness. Namely, (...) contemporary neuroscience offers definitions for universal physical processes that are in one-to-one correspondence with conscious experience. Since consciousness is a sufficient condition for life, these universal definitions of consciousness offer an interesting way forward in terms of the search for life in the cosmos. In this work, I systematically examine Integrated Information Theory (IIT), a well-established theory of consciousness, with the aim of applying it in both biological and astrobiological settings. Surprisingly, I discover major problems with Integrated Information Theory on two fronts: mathematical and epistemological. On the mathematical side, I show how degeneracies buried deep within the theory render it mathematically ill-defined, while on the epistemological side, I prove that the postulates of IIT are scientifically unfalsifiable and inherently metaphysical. Given that IIT is the preeminent theory of consciousness in modern neuroscience, these results have far-reaching implications in this field. In addition, I show that the epistemic issues of falsifiability that hamstring IIT apply quite generally to all contemporary theories of consciousness, which suggests a major reframing of the problem is necessary. The problems that I reveal in regard to defining consciousness offer an important parallel in regard to defining life, as both fields seek to define their topic of study in absence of an existing theoretical framework. To avoid metaphysical problems related to falsifiability, universal theories of both life and consciousness must be framed with respect to independent empirical observations that can be used to benchmark predictions from the theory. In this regard, I argue that the epistemic debate over scientific theories of consciousness should be used to inform the discussion regarding theoretical definitions of life. (shrink)

We consider existentially closed fields with several orderings, valuations, and p-valuations. We show that these structures are NTP2 of finite burden, but usually have the independence property. Mo...

Para favorecer la interacción disciplinar y recuperar la dimensión práctica del conocimiento matemático en la escuela secundaria, Yves Chevallard plantea la necesidad de introducir en los programas de estudio la matemática mixta. La matemática mixta, cuyo apogeo tuvo lugar en Europa entre los siglos XVI y XVIII, se propone el abordaje de problemas surgidos por fuera de la propia matemática valiéndose de nociones mecánicas -como la de centro de gravedad y fuerza centrífuga- y del empleo de variados instrumentos para realizar (...) las construcciones requeridas. En este trabajo consideramos a la matemática mixta en la cultura matemática de la segunda mitad del siglo XVII y, en dicho contexto, presentamos dos casos de la práctica matemática de G. W. Leibniz en los que la investigación matemática involucra el diseño de máquinas. La consideración de tales casos permite situar a la matemática mixta, siguiendo la terminología de Ian Hacking, en un terreno medio entre representar e intervenir. El terreno medio entre representar e intervenir es un valle fértil donde la matemática aporta a, y se nutre de, una multiplicidad de otros dominios. También es una vía de acceso para historizar el conocimiento matemático, destacando las condiciones materiales para su desarrollo y el importante rol de los problemas. Palabras clave: Práctica matemática, Resolución de problemas, Siglo XVII, Máquinas, Cultura material. (shrink)

The aim of this volume is to open up new perspectives and to raise new research questions about a unified approach to truth, modalities, and propositional attitudes. The volume's essays are grouped thematically around different research questions. The first theme concerns the tension between the theoretical role of the truth predicate in semantics and its expressive function in language. The second theme of the volume concerns the interaction of truth with modal and doxastic notions. The third theme covers higher-order solutions (...) to the semantic and modal paradoxes, providing an alternative to first-order solutions embraced in the first two themes. This book will be of interest to researchers working in epistemology, logic, philosophy of logic, philosophy of language, philosophy of mathematics, and semantics. (shrink)

Es común escuchar que el mundo Occidental debe a los árabes el descubrimiento del álgebra. No obstante, el desarrollo de esta disciplina puede interpretarse como un crisol de distintas tradiciones científicas que fue posible gracias a la clasificación, traducción y crítica tanto de los clásicos como de las obras que los árabes obtuvieron de los pueblos que conquistaron. Entre estos trabajos se encontraba Los Elementos de Euclides. Los Elementos fueron cuidadosamente traducidos durante el califato de Al-Ma’mūn por el matemático Mohammed (...) ibn-Musa Al-Khwārizmī, autor de Al-jabr wa’l muqābalah, quien sentó los fundamentos de la disciplina que más tarde sería conocida como álgebra y quien, en la primera parte de su obra, nos proporciona tres métodos para resolver tres tipos de ecuaciones que llama “ecuaciones combinadas”. A lo largo de este artículo se ofrecen argumentos para sostener que los métodos para resolver estas ecuaciones constituyen una reinterpretación, en el terreno algebraico, de los teoremas 6, 7 y 8 del segundo libro de Los Elementos de Euclides. Mi objetivo es dar respuesta a la siguiente pregunta: ¿Qué lectura de Los elementos Euclides posibilitó la emergencia del álgebra en el mundo árabe? Para responderla necesario explorar el acercamiento que los árabes tuvieron con el Libro II de Los Elementos, con el fin de proponer una interpretación de los posibles factores que los llevaron a formular el álgebra. Esto último, en particular, se encuentra en la primera parte de la obra de Al-Khwārizmī. Palabras clave: Álgebra, Al-Khwārizmī, Euclides, Ecuación, Teorema. (shrink)

Rosłanowski and Shelah [Small-large subgroups of the reals, Math. Slov. 68 473–484] asked whether every locally compact non-discrete group has a null but non-meager subgroup, and converse...

How a senior researcher from a developing country can build an organic academic enterprise. Drawing from childhood experience with nature, past works with the business sector, and philosophy of data-driven research, the essay presents a compelling case of letting young graduates work on big database-building projects: one on Vietnamese social sciences; the other is more than 80 years of the pioneer science in Vietnam—mathematics. Two national databases have enabled meaningful data-driven interactions with scientific policymakers.

We show that Weak Vopěnka’s Principle, which is the statement that the opposite category of ordinals cannot be fully embedded into the category of graphs, is equivalent to the large cardinal princi...

Hermann Weyl was one of the greatest mathematicians of the 20th century, with contributions to many branches of mathematics and physics. In 1918 he wrote a famous book, “Das Kontinuum”, on the foundations of mathematics. In that book he described mathematical analysis as a ‘house built on sand’, and tried to ‘replace this shifting foundation with pillars of enduring strength’. In this paper we reexamine and explain the philosophical and mathematical ideas that underly Weyl’s system in “Das Kontinuum”, and show (...) that they are still useful and relevant. We propose a precise formalization of that system, which is the first to be completely faithful to what is written in the book. Finally, we suggest that a certain set-theoretical modern system reflects better Weyl’s ideas than previous attempts (most notably by Feferman) of achieving this goal. (shrink)

In this dissertation we explore projective Fraïssé theory and its applications, as well as limitations, to the study of compact metrizable spaces. The goal of projective Fraïssé theory is to approximate spaces via classes of finite structures and glean topological or dynamical properties of a space by relating them to combinatorial features of the associated class of structures. Using the framework of compact metrixable structures, we establish general results which expand and help contextualize previous works in the field. Many proofs (...) in the domain of projective Fraïssé theory are carried out in a context dependent fashion and have thus far eluded clean generalizations. A reason is to be found in the lack of a clear understanding of which spaces are amenable to be studied via projective Fraïssé limits. We give both positive and negative results in this direction. We isolate a combinatorial condition which entails a correspondence between finite structures and regular quasi-partitions of compact metrizable spaces. This correspondence greatly aids the combinatorial-toplogical translation. We apply this machinery to study a class of one-dimensional compact metrizable spaces, which we call smooth fences. To this end, we isolate a class of finite structures—finite partial orders whose Hasse diagram is a forest—whose projective Fraïssé limit approximates a distinctive smooth fence with remarkable properties. We call it the Fraïssé fence and characterize it topologically by carefully exploiting the bridge between the combinatorial and topological worlds. We explore homogeneity and universality features of the Fraïssé fence and the properties of its spaces and endpoints, and provide some results on the dynamics of its group of homeomorphisms. The dissertation is partially based on [1, 2]. (shrink)

The number of bricks in a ziggurat is a sum of consecutive squares.

Sticking to elementary mathematics, this text is a short introduction to understanding historical and comparative counting systems. It gives a brief historical and contextual overview, along with showing how to read and count in a number of ancient systems including Egyptian, Babylonian, Mayan, Roman, Hebrew, Intuit, binary, Quipu and abacus.

This paper sought to investigate the fundamental differences in mathematics education through a comparison of curriculum of 2 countries—Singapore and Canada (as represented by Ontario)—in order to discover what the Ontario education system may learn from Singapore in terms of mathematics education. Mathematics curriculum were collected for Grades 1 to 8 for Ontario, and the equivalent in Singapore. The 2 curriculums were textually analyzed based on both the original and the revised Bloom’s taxonomy to expose their foci. The difference in (...) focus was then compared and discussed to find the best ways to improve the Ontario mathematics curriculum. With one of the best education systems in North America, the Ontario mathematics curriculum would only need to refocus its attention towards a more balanced approach, with greater focus on understanding through practices. Ontario would benefit greatly from a deeper research into the Singaporean math curriculum. (shrink)

The purpose of the research is to study the feasibility of using the combined modeling method in evaluation of business value. Modern approaches and methods of evaluating business value and the possibilities of combining them are explored. The peculiarities of the methodology of evaluating the business value by methods of Gordon Growth Model and Exit Multiple are disclosed. During the research the fair value of Luxoft company and the reasons for its deviation from the cost of sale are found. Luxoft’s (...) business value forecast is calculated by 2023. Recommendations for further development of the field of knowledge of modern business analyst are given. (shrink)

‘Mathematics is the science of the infinite, its goal the symbolic comprehension of the infinite with human, that is finite, means.’ Along this line, in The Open World, Hermann Weyl contrasted the desire to make the infinite accessible through finite processes, which underlies any theoretical investigation of reality, with the intuitive feeling for the infinite ‘peculiar to the Orient,’ which remains ‘indifferent to the concrete manifold of reality.’ But a critical analysis may acknowledge a valuable dialectical opposition. Struggling to spell (...) out the infinity of real numbers mathematicians come to see the active role of emptiness. Pondering over the essence of self-awareness, the Japanese philosopher Nishida Kitarō comes to see the ‘place’ where it abides as absolute nothingness. Thus, the two ways of seeing coalesce into a perspective in which infinity and nothingness mirror each other. (shrink)

This paper reconstructs Steel’s multiverse project in his ‘Gödel’s program’ (Steel [2014]), first by comparing it to those of Hamkins [2012] and Woodin [2011], then by detailed analysis what’s presented in Steel’s brief text. In particular, we reconstruct his notion of a ‘natural’ theory, describe his multiverse axioms and his translation function, and assess the resulting status of the Continuum Hypothesis. In the end, we reconceptualize the defect that Steel thinks CH might suffer from and isolate what it would take (...) to remove it while working within his framework. As our goal is to present as coherent and compelling a philosophical and mathematical story as we can, we allow ourselves to augment Steel’s story in places (e.g., in the treatment of Amalgamation) and to depart from it in others (e.g., the removal of ‘meaning’ from the account). The relevant mathematics is laid out in the appendices. (shrink)

Answering one of the main questions of [S.-D. Friedman, T. Hyttinen and V. Kulikov, Generalized descriptive set theory and classification theory, Mem. Amer. Math. Soc. 230 80, Chap. 7]...

In recent decades, the development of sciences and technologies had a significant impact in society. This impact has been object of analysis from several standpoints, i.e., scientific, communication, historical and anthropological. Consequently, serious changes were required by the society. One of these has been the emerging relationship science in society and its foundations of applied sciences. A related foundational challenging is the educational process, which was and still is an unlimited challenge for teachers and professors: i.e., levels of understanding, curricula, (...) activing critical engagement, transfer knowledge—and—skills, management, classroom and subsequently pre-service teachers need special teacher education. Taking into account Joule’s bicentenary commemoration in physics and Nature of Science teaching this paper introduces to a level of inquiring within historical and NoS approaches in the pre-service teachers, typically science, technology, engineering and mathematics. In particular, history and historiography of Joule’s physics are dealt with. (shrink)