One-side peano curves of fractal genus 9

This paper completes the analysis (begun by E.V. Shchepin and the author in 2008) of regular Peano curves of genus 9 in search of a curve with the minimum square-to-linear ratio. One-side regular Peano curves of genus 9 are considered, and, among these curves, a class of minimal curves with a square-to-linear ratio of 5 2/3 is singled out. A new language to describe curves is introduced which significantly simplifies the coding of these curves.     

On the peano theorem in infinite-dimensional spaces

New sufficient conditions for a first-order ordinary differential equation in an infinite Banach space to be locally solvable and for the solution to depend continuously on a parameter are obtained. The results are applied to an integrodifferential equation.Translated from Matematicheskie Zametki, Vol. 11, No. 5, pp. 569–576, May, 1972.The author is grateful to B. N. Sadovskii for posing the problem and for his continuous interest in the work.     

Smooth curves linked to thick curves

In this paper we construct smooth irreducible spacecurves C which link geometrically by surfaces of minimal degree containingC to curves of generic embedding dimension three. This produces interesting behavior with respect to both C and . The curves link to smooth connected curves by surfaces of low degree butcannot link to smooth connected curves by surfaces of high degree.The curves C give counterexamples to a conjecture of Martin-Deschamps and Perrin.     

Fractal Interpolation Surfaces derived from Fractal Interpolation Functions

Based on the construction of Fractal Interpolation Functions, a new construction of Fractal Interpolation Surfaces on arbitrary data is presented and some interesting properties of them are proved. Finally, a lower bound of their box counting dimension is provided.     

Fractal balls

To the best of our knowledge, the analysis of densely folded media has not deserved special attention. The stress and strain analysis of this type of structures involves considerable difficulties concerning very strong non-linear effects. This paper presents a theory that could be classified as a geometric theory of folded media, in the sense that it ultimately leads to a kind of geometric constitutive law, or, in other words, a law that establishes the relationship between the geometry of the folded media and other variables such as the confinement capacity and the plastic strain energy. The discussion presented here is restricted to the particular case of compact balls produced by crushing together very thin plates or sheets. It is shown that both the geometry of the folded sheet and the plastic work density can be used as self-similarity tests. These criteria are equivalent for the case of thin plates or sheets made of the same material and with the same thickness. For the general case, the geometry of the folded sheet is not valid anymore as similarity criterion but there are strong arguments in favor of the plastic work density as a general criterion. If self-similarity is obtained for a ball set resulting from crumpling thin plates or sheets, it is possible to define two variables, the packing capacity and the slenderness ratio, that are related according to a power law. That is, the balls have a fractal representation. The power law scaling is derived from the mass conservation principle. The theory is claimed to be valid provided that certain assumptions referring to the geometry and material properties are satisfied. The results have shown that the theory is coherent and worthwhile of experimental validation. Some applications are suggested. A possible challenging investigation is related to the optimal geometry of biological membranes.     

Fractal Continuation

A fractal function is a function whose graph is the attractor of an iterated function system. This paper generalizes analytic continuation of an analytic function to continuation of a fractal function.     

Fractal Approximation

In the present article every complex square integrable function defined in a real bounded interval is approached by means of a complex fractal function. The approximation depends on a partition of the interval and a vectorial parameter of the iterated function system providing the fractal attractor. The original may be discontinuous or undefined in a set of zero measure. The fractal elements can modify the features of the originals, for instance their character of smooth or non-smooth. The properties of the operator mapping every function into its fractal analogue are studied in the context of the uniform and least square norms. In particular, the transformation provides a decomposition of the set of square integrable maps. An orthogonal system of fractal functions is constructed explicitly for this space. Sufficient conditions for the uniform convergence of the fractal series expansion corresponding to this basis are also deduced. The fractal approximation of real functions is obtained as a particular case.     

量化分形图形的新指数——简便分形指数

分形的广泛存在性已被普遍接受,然而分形维数的现有定义计算得到的结果是:不同的分形维数定义得到不同的分形维数值,甚至会出现不同的变化趋势,且在应用时使用的最小二乘回归结果不稳定,导致数值应用也会受影响,出现这些现象主要归咎于现有分形维数定义的严格性、抽象性以及分形图形的码尺效应.为避免这些问题,本文结合分形图形的长尾分布特征及自相似性提出一个新的分形量化形式——简便分形指数,并阐述了该定义背后的分形原理及计算方法,简便分形指数越大,形状复杂程度越高.最后本文利用岩石裂隙图像说明简便分形指数对不同裂隙网络复杂性描述的准确性,验证其作为分形图形量化方法的合理性及便利性.     

On universal elliptic curves over Igusa curves

Summary The purpose of this note is to introduce the arithmetic, study of the universal elliptic curve over Igusa curves. Specifically, its Hasse-WeilL-function is computed in terms of modular forms and is shown to have interesting zeros. Explicit examples are presented for which the Birch and Swinnerton-Dyer conjecture is verified.This paper summarizes part of the author's Ph.D. thesis. He wishes to thank the Sloan Foundation for financial support in the form of a Doctoral Dissertation Fellowship and his advisor, Dick Gross, for mathematical guidance and inspirational enthusiasm.To my parents in their 50th year     

Fractal Haar system

The Haar system is an alternative to the classical Fourier bases, being particularly useful for the approximation of discontinuities. The article tackles the construction of a set of fractal functions close to the Haar set. The new system holds the property of constitution of bases of the Lebesgue spaces of p-integrable functions on compact intervals. Likewise, the associated fractal series of a continuous function is uniformly convergent. The case p=2 owns some peculiarities and is studied separately.     

Area-filling curves

Archiv der Mathematik - In this paper, we study area-filling curves, i.e. continuous and injective mappings defined on [0, 1] whose graph has positive measure. Current literature calls...     

Equimodular curves

This paper is motivated by a problem that arises in the study of partition functions of Potts models, including as a special case chromatic polynomials. When the underlying graphs have the form of ‘bracelets’, the chromatic polynomials can be expressed in terms of the eigenvalues of a matrix. In this situation a theorem of Beraha, Kahane and Weiss asserts that the zeros of the polynomials approach the curves on which the matrix has two eigenvalues with equal modulus. It is shown here that (in general) these ‘equimodular’ curves comprise a number of segments, the end-points of which are the roots (possibly coincident) of a polynomial equation. The equation represents the vanishing of a discriminant, and the segments are in bijective correspondence with the double roots of another polynomial equation, which is significantly simpler than the discriminant equation. Singularities of the segments can occur, corresponding to the vanishing of a Jacobian. In addition, it is proved by algebraic means that the equimodular curves for a reducible matrix are closed curves. The question of dominance is investigated, and a method of constructing the dominant equimodular curves for a reducible matrix is suggested. These results are illustrated by explicit calculations in a specific case.