Symbolic language in early modern mathematics: The Algebra of Pierre Hérigone (1580–1643)

The creation of a formal mathematical language was fundamental to making mathematics algebraic. A landmark in this process was the publication of In artem analyticem isagoge by François Viète (1540–1603) in 1591. This work was diffused through many other algebra texts, as in the section entitled Algebra in the Cursus mathematicus (Paris, 1634, 1637, 1642; second edition 1644) by Pierre Hérigone (1580–1643). The aim of this paper is to analyze several features of Hérigone's Algebra. Hérigone was one of the first mathematicians to consider that symbolic language might be used as a universal language for dealing with pure and mixed mathematics. We show that, although Hérigone generally used Viète's statements, his notation, presentation style, and procedures in his algebraic proofs were quite different from Viète's. In addition, we emphasize how Hérigone handled algebraic operations and geometrical procedures by making use of propositions from Euclid's Elements formulated in symbolic language.     

Index Sets in Modeling Languages

Index sets are an integral and fundamental part of every mathematical modeling language. They assist the modeler in grouping various objects and entities. Index sets are also used extensively in the mathematical notation to write an expression in a concise way. An example is the sigma notation for formulating the summation of an unknown number n of terms. In this paper, the concept of index set is introduced in the context of modeling languages. The main objective is to propose an extension and generalization of the concept of index sets, which is the concept of hierarchical index sets. The paper concludes with an application, which clearly shows the usefulness of this concept.     

The use of phase portraits to visualize and investigate isolated singular points of complex functions

ABSTRACT

Undergraduate students usually study Laurent series in a standard course of Complex Analysis. One of the major applications of Laurent series is the classification of isolated singular points of complex functions. Although students are able to find series representations of functions, they may struggle to understand the meaning of the behaviour of the function near isolated singularities. In this paper, I briefly describe the method of domain colouring to create enhanced phase portraits to visualize and study isolated singularities of complex functions. Ultimately this method for plotting complex functions might help to enhance students' insight, in the spirit of learning by experimentation. By analysing the representations of singularities and the behaviour of the functions near their singularities, students can make conjectures and test them mathematically, which can help to create significant connections between visual representations, algebraic calculations and abstract mathematical concepts.     

Equivariant Tamagawa Numbers and Galois Module Theory I

Let L/K be a finite Galois extension of number fields. We use complexes arising from the étale cohomology of Z on open subschemes of Spec O _L to define a canonical element of the relative algebraic K-group K ₀Z[Gal(L/K)], R. We establish some basic properties of this element, and then use it to reinterpret and refine conjectures of Stark, of Chinburg and of Gruenberg, Ritter and Weiss. Our results precisely explain the connection between these conjectures and the seminal work of Bloch and Kato concerning Tamagawa numbers. This provides significant new insight into these important conjectures and also allows one to use powerful techniques from arithmetic algebraic geometry to obtain new evidence in their favour.     

Turnaround Students in High School Mathematics: Constructing Identities of Competence Through Mathematical Worlds

This study investigates prospective secondary teachers’ cognitive difficulties and mathematical ideas involved in making connections among representations. We implemented a three-week teaching unit to help prospective secondary mathematics teachers develop understanding of big ideas that are critical to formulating connections among representations, in the context of conic curves. Qualitative analysis of data showed that most undergraduate mathematics majors and minors in this study struggled with variation, the Cartesian Connection, and other affiliated ideas such as graph as a locus of points. Furthermore, they were unable to identify basic metric relations encoded in algebraic expressions such as the distance between points, which further compounded their difficulties in making connections among representations. We argue that mathematics teacher education needs more focus on these ideas so that their graduates can successfully teach these big ideas in their future instruction.     

Automorphic lifts of prescribed types

We prove a variety of results on the existence of automorphic Galois representations lifting a residual automorphic Galois representation. We prove a result on the structure of deformation rings of local Galois representations, and deduce from this and the method of Khare and Wintenberger a result on the existence of modular lifts of specified type for Galois representations corresponding to Hilbert modular forms of parallel weight 2. We discuss some conjectures on the weights of n-dimensional mod p Galois representations. Finally, we use recent work of Taylor to prove level raising and lowering results for n-dimensional automorphic Galois representations.     

Integrating the Study of Trigonometry,Vectors, and Force Through Modeling

In this case study, we have investigated the construction of understanding of the motion of an object down an inclined plane which takes place through the process of model building. This study was conducted in an integrated algebra, trigonometry, and physics class at an alternative public school. The components of the modeling process explored in the study are the action of building representations and relationships from physical phenomena, the use of a simulation environment to explore conjectures, and the iterative process of developing and validating a solution through the use of a multirepresentational analytic tool. Four major results related to student model building emerged from this study. First, students pursued problems with far more diversity in approaches than the problem itself might have initially suggested. Second, this analysis challenges conventional notions of closure and completeness. Third, the integration of the simulation environment provided access to an expert's model that could be used as the students built their own model of the phenomena being investigated. The fourth theme is that of progressive complexity in the student model as a structure that was built over an extended period of time. The implications of these results for both instruction and curriculum are discussed.     

Algebraic modular forms

In this paper, we develop an algebraic theory of modular forms, for connected, reductive groupsG overQ with the property that every arithmetic subgroup Γ ofG(Q) is finite. This theory includes our previous work [15] on semi-simple groupsG withG(R) compact, as well as the theory of algebraic Hecke characters for Serre tori [20]. The theory of algebraic modular forms leads to a workable theory of modular forms (modp), which we hope can be used to parameterize odd modular Galois representations. The theory developed here was inspired by a letter of Serre to Tate in 1987, which has appeared recently [21]. I want to thank Serre for sending me a copy of this letter, and for many helpful discussions on the topic.     

Integer number sense and notation: A case study of a student with a mathematics learning disability

Although approximately 6% of students have a mathematics learning disability (MLD) also known as dyscalculia, little is known about how MLD impacts students beyond basic arithmetic. In this study we focused on one mathematical topic foundational to algebra – integer operations – and conducted a videotaped design experiment with one student with MLD. Through 14 teaching episodes we explored the ways in which standard mathematical tools (e.g., symbols, representations) were inaccessible and evaluated the design of alternative tools. Our detailed retrospective analysis revealed that the student had an unconventional understanding of integer quantities and symbolic notation, which resulted in issues of accessibility and persistent difficulties. Deliberate attempts to address inaccessibility revealed nuances in the student’s understanding, and suggests that both number sense and notational issues needed to be addressed in tandem. Implications for instruction are discussed.     

Arithmetic gravity: An approach to adelic physics via algebraic spaces

In this paper we present an approach to adelic physics via algebraic spaces. Relative algebraic spaces X → S are considered as fundamental objects which describe space-time. This yields a number field invariant formulation of general relativity which, in the special case S = Spec ℂ, may be translated back into the language of manifolds. With regard to adelic physics the case of an excellent Dedekind scheme S as base scheme is of interest (e.g. S = Spec ℤ). Some solutions of the arithmetic Einstein equations are studied.     

Logical form,mathematical practice,and Frege's Begriffsschrift

For over a century we have been reading Frege's Begriffsschrift notation as a variant of standard notation. But Frege's notation can also be read differently, in a way enabling us to understand how reasoning in Begriffsschrift is at once continuous with and a significant advance beyond earlier mathematical practices of reasoning within systems of signs. It is this second reading that I outline here, beginning with two preliminary claims. First, I show that one does not reason in specially devised systems of signs of mathematics as one reasons in natural language; the signs are not abbreviations of words. Then I argue that even given a system of signs within which to reason in mathematics, there are two ways one can read expressions involving those signs, either mathematically or mechanically. These two lessons are then applied to a reading of Frege's proof of Theorem 133 in Part III of his 1879 logic, a proof that Frege claims is at once strictly deductive and ampliative, a real extension of our knowledge. In closing, I clarify what this might mean, and how it might be possible.     

The representation of meromorphic solutions for a class of odd order algebraic differential equations and its applications

In this paper, we employ the Nevanlinna's value distribution theory to investigate the existence of meromorphic solutions of algebraic differential equations. We obtain the representations of all meromorphic solutions for a class of odd order algebraic differential equations with the weak ?p,q?and dominant conditions. Moreover, we give the complex method to find all traveling wave exact solutions of corresponding partial differential equations. As an example, we obtain all meromorphic solutions of the Kuramoto–Sivashinsky equation by using our complex method. Our results show that the complex method provides a powerful mathematical tool for solving great many nonlinear partial differential equations in mathematical physics. Copyright © 2014 John Wiley & Sons, Ltd.     

Additive representations of integers

In this paper we shall mainly study additive representations of integers prime to the firstm primes as a sum of some integers having a peculiar property. The conjectures of Goldbach and twin primes are also observed in connection with these representations of integers.     

Helping students build a path of understanding from ratio and proportion to decimal notation

Various studies have shown that students of all levels struggle to understand decimal numbers. This paper discusses a novel approach to increasing students’ conceptual understanding of decimal numbers. Rather than approach decimal notation as a discrete and separate mathematical topic, this approach enables students to work with contextual problems to gain a solid understanding of ratio and proportion. Using their understanding of ratio and proportion as a foundation, students can then build connected and related understandings of fractions, decimals and percents. The study discussed in this paper illustrates that grounding decimal instruction in the broader context of ratio can help students gain deeper conceptual understandings of decimal notation as well as fractions and percents.     

Comparing stage-scenario with nodal formulation for multistage stochastic problems

To solve real life problems under uncertainty in Economics, Finance, Energy, Transportation and Logistics, the use of stochastic optimization is widely accepted and appreciated. However, the nature of stochastic programming leads to a conflict between adaptability to reality and tractability. To formulate a multistage stochastic model, two types of formulations are typically adopted: the so-called stage-scenario formulation named also formulation with explicit non-anticipativity constraints and the so-called nodal formulation named also formulation with implicit non-anticipativity constraints. Both of them have advantages and disadvantages. This work aims at helping the scholars and practitioners to understand the two types of notation and, in particular, to reformulate with the nodal formulation a model that was originally defined with the stage-scenario formulation presenting this implementation in the algebraic language GAMS. In addition, this work presents an empirical analysis applying the two formulations both without any further decomposition to perform a fair comparison. In this way, we show that the difficulties to implement the model with the nodal formulation are somehow reworded making the problem tractable without any decomposition algorithm. Still, we remark that in some other applications the stage-scenario formulation could be more helpful to understand the structure of the problem since it allows to relax the non-anticipativity constraints.

     

Additive representations of integers

In this paper we shall mainly study additive representations of integers prime to the first m primes as a sum of some integers having a peculiar property. The conjectures of Goldbach and twin primes are also observed in connection with these representations of integers. Received: 20 October 1997     

Partially finite convex programming,Part II: Explicit lattice models

In Part I of this work we derived a duality theorem for partially finite convex programs, problems for which the standard Slater condition fails almost invariably. Our result depended on a constraint qualification involving the notion ofquasi relative interior. The derivation of the primal solution from a dual solution depended on the differentiability of the dual objective function: the differentiability of various convex functions in lattices was considered at the end of Part I. In Part II we shall apply our results to a number of more concrete problems, including variants of semi-infinite linear programming,L ¹ approximation, constrained approximation and interpolation, spectral estimation, semi-infinite transportation problems and the generalized market area problem of Lowe and Hurter (1976). As in Part I, we shall use lattice notation extensively, but, as we illustrated there, in concrete examples lattice-theoretic ideas can be avoided, if preferred, by direct calculation.     

The Chow Motive of a K3 Surface

In this note we present some results on the Chow motive h(X) of an algebraic surface X and relate them to the conjectures of Bloch, Beilinson and Murre. In particular we illustrate the relations between the finite-dimensionality of h(X) and the geometric properties of the surface. Then we focus on the case, where the conjectures are still open, of a complex K3 surface and prove some results which give some evidence to the finite-dimensionality of h(X).     

On a family of sequences defined recursively in (II)

This paper is a second part to previous work (see Finite Fields Appl. 9 (2003) 211). Different conjectures stated there are proven here. We are concerned with sequences (x_i)_i1 in such that the continued fraction expansion [x₁T,x₂T,…,x_nT,…] in is algebraic over . These algebraic elements correspond in some way to quadratic real numbers for which the continued fraction expansion is well known.     

Tannakian Approach to Linear Differential Algebraic Groups

Tannaka’s theorem states that a linear algebraic group G is determined by the category of finite-dimensional G-modules and the forgetful functor. We extend this result to linear differential algebraic groups by introducing a category corresponding to their representations and show how this category determines such a group. This work was partially supported by NSF Grant CCR-0096842 and by the Russian Foundation for Basic Research, project no. 05-01-00671.