Abstract Similarity, Fractals and Chaos
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Fractal (Mandelbrot and Julia) Zero-Knowledge Proof of Identity
Journal of Computer Science 4 (5): 408-414, 2008 ISSN 1549-3636 © 2008 Science Publications Fractal (Mandelbrot and Julia) Zero-Knowledge Proof of Identity Mohammad Ahmad Alia and Azman Bin Samsudin School of Computer Sciences, University Sains Malaysia, 11800 Penang, Malaysia Abstract: We proposed a new zero-knowledge proof of identity protocol based on Mandelbrot and Julia Fractal sets. The Fractal based zero-knowledge protocol was possible because of the intrinsic connection between the Mandelbrot and Julia Fractal sets. In the proposed protocol, the private key was used as an input parameter for Mandelbrot Fractal function to generate the corresponding public key. Julia Fractal function was then used to calculate the verified value based on the existing private key and the received public key. The proposed protocol was designed to be resistant against attacks. Fractal based zero-knowledge protocol was an attractive alternative to the traditional number theory zero-knowledge protocol. Key words: Zero-knowledge, cryptography, fractal, mandelbrot fractal set and julia fractal set INTRODUCTION Zero-knowledge proof of identity system is a cryptographic protocol between two parties. Whereby, the first party wants to prove that he/she has the identity (secret word) to the second party, without revealing anything about his/her secret to the second party. Following are the three main properties of zero- knowledge proof of identity[1]: Completeness: The honest prover convinces the honest verifier that the secret statement is true. Soundness: Cheating prover can’t convince the honest verifier that a statement is true (if the statement is really false). Fig. 1: Zero-knowledge cave Zero-knowledge: Cheating verifier can’t get anything Zero-knowledge cave: Zero-Knowledge Cave is a other than prover’s public data sent from the honest well-known scenario used to describe the idea of zero- prover. -
The Topological Entropy Conjecture
mathematics Article The Topological Entropy Conjecture Lvlin Luo 1,2,3,4 1 Arts and Sciences Teaching Department, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China; [email protected] or [email protected] 2 School of Mathematical Sciences, Fudan University, Shanghai 200433, China 3 School of Mathematics, Jilin University, Changchun 130012, China 4 School of Mathematics and Statistics, Xidian University, Xi’an 710071, China Abstract: For a compact Hausdorff space X, let J be the ordered set associated with the set of all finite open covers of X such that there exists nJ, where nJ is the dimension of X associated with ¶. Therefore, we have Hˇ p(X; Z), where 0 ≤ p ≤ n = nJ. For a continuous self-map f on X, let a 2 J be f an open cover of X and L f (a) = fL f (U)jU 2 ag. Then, there exists an open fiber cover L˙ f (a) of X induced by L f (a). In this paper, we define a topological fiber entropy entL( f ) as the supremum of f ent( f , L˙ f (a)) through all finite open covers of X = fL f (U); U ⊂ Xg, where L f (U) is the f-fiber of − U, that is the set of images f n(U) and preimages f n(U) for n 2 N. Then, we prove the conjecture log r ≤ entL( f ) for f being a continuous self-map on a given compact Hausdorff space X, where r is the maximum absolute eigenvalue of f∗, which is the linear transformation associated with f on the n L Cechˇ homology group Hˇ ∗(X; Z) = Hˇ i(X; Z). -
Halloweierstrass
Happy Hallo WEIERSTRASS Did you know that Weierestrass was born on Halloween? Neither did we… Dmitriy Bilyk will be speaking on Lacunary Fourier series: from Weierstrass to our days Monday, Oct 31 at 12:15pm in Vin 313 followed by Mesa Pizza in the first floor lounge Brought to you by the UMN AMS Student Chapter and born in Ostenfelde, Westphalia, Prussia. sent to University of Bonn to prepare for a government position { dropped out. studied mathematics at the M¨unsterAcademy. University of K¨onigsberg gave him an honorary doctor's degree March 31, 1854. 1856 a chair at Gewerbeinstitut (now TU Berlin) professor at Friedrich-Wilhelms-Universit¨atBerlin (now Humboldt Universit¨at) died in Berlin of pneumonia often cited as the father of modern analysis Karl Theodor Wilhelm Weierstrass 31 October 1815 { 19 February 1897 born in Ostenfelde, Westphalia, Prussia. sent to University of Bonn to prepare for a government position { dropped out. studied mathematics at the M¨unsterAcademy. University of K¨onigsberg gave him an honorary doctor's degree March 31, 1854. 1856 a chair at Gewerbeinstitut (now TU Berlin) professor at Friedrich-Wilhelms-Universit¨atBerlin (now Humboldt Universit¨at) died in Berlin of pneumonia often cited as the father of modern analysis Karl Theodor Wilhelm Weierstraß 31 October 1815 { 19 February 1897 born in Ostenfelde, Westphalia, Prussia. sent to University of Bonn to prepare for a government position { dropped out. studied mathematics at the M¨unsterAcademy. University of K¨onigsberg gave him an honorary doctor's degree March 31, 1854. 1856 a chair at Gewerbeinstitut (now TU Berlin) professor at Friedrich-Wilhelms-Universit¨atBerlin (now Humboldt Universit¨at) died in Berlin of pneumonia often cited as the father of modern analysis Karl Theodor Wilhelm Weierstraß 31 October 1815 { 19 February 1897 sent to University of Bonn to prepare for a government position { dropped out. -
On Fractal Properties of Weierstrass-Type Functions
Proceedings of the International Geometry Center Vol. 12, no. 2 (2019) pp. 43–61 On fractal properties of Weierstrass-type functions Claire David Abstract. In the sequel, starting from the classical Weierstrass function + 8 n n defined, for any real number x, by (x) = λ cos (2 π Nb x), where λ W n=0 ÿ and Nb are two real numbers such that 0 λ 1, Nb N and λ Nb 1, we highlight intrinsic properties of curious mapsă ă which happenP to constituteą a new class of iterated function system. Those properties are all the more interesting, in so far as they can be directly linked to the computation of the box dimension of the curve, and to the proof of the non-differentiabilty of Weierstrass type functions. Анотація. Метою даної роботи є узагальнення попередніх результатів автора про класичну функцію Вейерштрасса та її графік. Його можна отримати як границю послідовності префракталів, тобто графів, отри- маних за допомогою ітераційної системи функцій, які, як правило, не є стискаючими відображеннями. Натомість вони мають в деякому сенсі еквівалентну властивість до стискаючих відображень, оскільки на ко- жному етапі ітераційного процесу, який дає змогу отримати префра- ктали, вони зменшують двовимірні міри Лебега заданої послідовності прямокутників, що покривають криву. Такі системи функцій відіграють певну роль на першому кроці процесу побудови підкови Смейла. Вони можуть бути використані для доведення недиференційованості функції Вейєрштрасса та обчислення box-розмірності її графіка, а також для по- будови більш широких класів неперервних, але ніде не диференційовних функцій. Останнє питання ми вивчатимемо в подальших роботах. 2010 Mathematics Subject Classification: 37F20, 28A80, 05C63 Keywords: Weierstrass function; non-differentiability; iterative function systems DOI: http://dx.doi.org/10.15673/tmgc.v12i2.1485 43 44 Cl. -
Continuous Nowhere Differentiable Functions
2003:320 CIV MASTER’S THESIS Continuous Nowhere Differentiable Functions JOHAN THIM MASTER OF SCIENCE PROGRAMME Department of Mathematics 2003:320 CIV • ISSN: 1402 - 1617 • ISRN: LTU - EX - - 03/320 - - SE Continuous Nowhere Differentiable Functions Johan Thim December 2003 Master Thesis Supervisor: Lech Maligranda Department of Mathematics Abstract In the early nineteenth century, most mathematicians believed that a contin- uous function has derivative at a significant set of points. A. M. Amp`ereeven tried to give a theoretical justification for this (within the limitations of the definitions of his time) in his paper from 1806. In a presentation before the Berlin Academy on July 18, 1872 Karl Weierstrass shocked the mathematical community by proving this conjecture to be false. He presented a function which was continuous everywhere but differentiable nowhere. The function in question was defined by ∞ X W (x) = ak cos(bkπx), k=0 where a is a real number with 0 < a < 1, b is an odd integer and ab > 1+3π/2. This example was first published by du Bois-Reymond in 1875. Weierstrass also mentioned Riemann, who apparently had used a similar construction (which was unpublished) in his own lectures as early as 1861. However, neither Weierstrass’ nor Riemann’s function was the first such construction. The earliest known example is due to Czech mathematician Bernard Bolzano, who in the years around 1830 (published in 1922 after being discovered a few years earlier) exhibited a continuous function which was nowhere differen- tiable. Around 1860, the Swiss mathematician Charles Cell´erieralso discov- ered (independently) an example which unfortunately wasn’t published until 1890 (posthumously). -
Topological Invariance of the Sign of the Lyapunov Exponents in One-Dimensional Maps
PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY Volume 134, Number 1, Pages 265–272 S 0002-9939(05)08040-8 Article electronically published on August 19, 2005 TOPOLOGICAL INVARIANCE OF THE SIGN OF THE LYAPUNOV EXPONENTS IN ONE-DIMENSIONAL MAPS HENK BRUIN AND STEFANO LUZZATTO (Communicated by Michael Handel) Abstract. We explore some properties of Lyapunov exponents of measures preserved by smooth maps of the interval, and study the behaviour of the Lyapunov exponents under topological conjugacy. 1. Statement of results In this paper we consider C3 interval maps f : I → I,whereI is a compact interval. We let C denote the set of critical points of f: c ∈C⇔Df(c)=0.We shall always suppose that C is finite and that each critical point is non-flat: for each ∈C ∈ ∞ 1 ≤ |f(x)−f(c)| ≤ c ,thereexist = (c) [2, )andK such that K |x−c| K for all x = c.LetM be the set of ergodic Borel f-invariant probability measures. For every µ ∈M, we define the Lyapunov exponent λ(µ)by λ(µ)= log |Df|dµ. Note that log |Df|dµ < +∞ is automatic since Df is bounded. However we can have log |Df|dµ = −∞ if c ∈Cis a fixed point and µ is the Dirac-δ measure on c. It follows from [15, 1] that this is essentially the only way in which log |Df| can be non-integrable: if µ(C)=0,then log |Df|dµ > −∞. The sign, more than the actual value, of the Lyapunov exponent can have signif- icant implications for the dynamics. A positive Lyapunov exponent, for example, indicates sensitivity to initial conditions and thus “chaotic” dynamics of some kind. -
Writing the History of Dynamical Systems and Chaos
Historia Mathematica 29 (2002), 273–339 doi:10.1006/hmat.2002.2351 Writing the History of Dynamical Systems and Chaos: View metadata, citation and similar papersLongue at core.ac.uk Dur´ee and Revolution, Disciplines and Cultures1 brought to you by CORE provided by Elsevier - Publisher Connector David Aubin Max-Planck Institut fur¨ Wissenschaftsgeschichte, Berlin, Germany E-mail: [email protected] and Amy Dahan Dalmedico Centre national de la recherche scientifique and Centre Alexandre-Koyre,´ Paris, France E-mail: [email protected] Between the late 1960s and the beginning of the 1980s, the wide recognition that simple dynamical laws could give rise to complex behaviors was sometimes hailed as a true scientific revolution impacting several disciplines, for which a striking label was coined—“chaos.” Mathematicians quickly pointed out that the purported revolution was relying on the abstract theory of dynamical systems founded in the late 19th century by Henri Poincar´e who had already reached a similar conclusion. In this paper, we flesh out the historiographical tensions arising from these confrontations: longue-duree´ history and revolution; abstract mathematics and the use of mathematical techniques in various other domains. After reviewing the historiography of dynamical systems theory from Poincar´e to the 1960s, we highlight the pioneering work of a few individuals (Steve Smale, Edward Lorenz, David Ruelle). We then go on to discuss the nature of the chaos phenomenon, which, we argue, was a conceptual reconfiguration as -
Complex Numbers and Colors
Complex Numbers and Colors For the sixth year, “Complex Beauties” provides you with a look into the wonderful world of complex functions and the life and work of mathematicians who contributed to our understanding of this field. As always, we intend to reach a diverse audience: While most explanations require some mathemati- cal background on the part of the reader, we hope non-mathematicians will find our “phase portraits” exciting and will catch a glimpse of the richness and beauty of complex functions. We would particularly like to thank our guest authors: Jonathan Borwein and Armin Straub wrote on random walks and corresponding moment functions and Jorn¨ Steuding contributed two articles, one on polygamma functions and the second on almost periodic functions. The suggestion to present a Belyi function and the possibility for the numerical calculations came from Donald Marshall; the November title page would not have been possible without Hrothgar’s numerical solution of the Bla- sius equation. The construction of the phase portraits is based on the interpretation of complex numbers z as points in the Gaussian plane. The horizontal coordinate x of the point representing z is called the real part of z (Re z) and the vertical coordinate y of the point representing z is called the imaginary part of z (Im z); we write z = x + iy. Alternatively, the point representing z can also be given by its distance from the origin (jzj, the modulus of z) and an angle (arg z, the argument of z). The phase portrait of a complex function f (appearing in the picture on the left) arises when all points z of the domain of f are colored according to the argument (or “phase”) of the value w = f (z). -
Pathological” Functions and Their Classes
Properties of “Pathological” Functions and their Classes Syed Sameed Ahmed (179044322) University of Leicester 27th April 2020 Abstract This paper is meant to serve as an exposition on the theorem proved by Richard Aron, V.I. Gurariy and J.B. Seoane in their 2004 paper [2], which states that ‘The Set of Dif- ferentiable but Nowhere Monotone Functions (DNM) is Lineable.’ I begin by showing how certain properties that our intuition generally associates with continuous or differen- tiable functions can be wrong. This is followed by examples of functions with surprisingly unintuitive properties that have appeared in mathematical literature in relatively recent times. After a brief discussion of some preliminary concepts and tools needed for the rest of the paper, a construction of a ‘Continuous but Nowhere Monotone (CNM)’ function is provided which serves as a first concrete introduction to the so called “pathological functions” in this paper. The existence of such functions leaves one wondering about the ‘Differentiable but Nowhere Monotone (DNM)’ functions. Therefore, the next section of- fers a description of how the 2004 paper by the three authors shows that such functions are very abundant and not mere fancy counter-examples that can be called “pathological.” 1Introduction A wide variety of assumptions about the nature of mathematical objects inform our intuition when we perform calculations. These assumptions have their utility because they help us perform calculations swiftly without being over skeptical or neurotic. The problem, however, is that it is not entirely obvious as to which assumptions are legitimate and can be rigorously justified and which ones are not. -
A New Digital Signature Scheme Based on Mandelbrot and Julia Fractal Sets
American Journal of Applied Sciences 4 (11): 848-856, 2007 ISSN 1546-9239 © 2007 Science Publications A New Digital Signature Scheme Based on Mandelbrot and Julia Fractal Sets Mohammad Ahmad Alia and Azman Bin Samsudin School of Computer Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia Abstract: This paper describes a new cryptographic digital signature scheme based on Mandelbrot and Julia fractal sets. Having fractal based digital signature scheme is possible due to the strong connection between the Mandelbrot and Julia fractal sets. The link between the two fractal sets used for the conversion of the private key to the public key. Mandelbrot fractal function takes the chosen private key as the input parameter and generates the corresponding public-key. Julia fractal function then used to sign the message with receiver's public key and verify the received message based on the receiver's private key. The propose scheme was resistant against attacks, utilizes small key size and performs comparatively faster than the existing DSA, RSA digital signature scheme. Fractal digital signature scheme was an attractive alternative to the traditional number theory digital signature scheme. Keywords: Fractals Cryptography, Digital Signature Scheme, Mandelbrot Fractal Set, and Julia Fractal Set INTRODUCTION Cryptography is the science of information security. Cryptographic system in turn, is grouped according to the type of the key system: symmetric (secret-key) algorithms which utilizes the same key (see Fig. 1) for both encryption and decryption process, and asymmetric (public-key) algorithms which uses different, but mathematically connected, keys for encryption and decryption (see Fig. 2). In general, Fig. 1: Secret-key scheme. -
Ensembles Fractals, Mesure Et Dimension
Ensembles fractals, mesure et dimension Jean-Pierre Demailly Institut Fourier, Universit´ede Grenoble I, France & Acad´emie des Sciences de Paris 19 novembre 2012 Conf´erence au Lyc´ee Champollion, Grenoble Jean-Pierre Demailly, Lyc´ee Champollion - Grenoble Ensembles fractals, mesure et dimension Les fractales sont partout : arbres ... fractale pouvant ˆetre obtenue comme un “syst`eme de Lindenmayer” Jean-Pierre Demailly, Lyc´ee Champollion - Grenoble Ensembles fractals, mesure et dimension Poumons ... Jean-Pierre Demailly, Lyc´ee Champollion - Grenoble Ensembles fractals, mesure et dimension Chou broccoli Romanesco ... Jean-Pierre Demailly, Lyc´ee Champollion - Grenoble Ensembles fractals, mesure et dimension Notion de dimension La dimension d’un espace (ensemble de points dans lequel on se place) est classiquement le nombre de coordonn´ees n´ecessaires pour rep´erer un point de cet espace. C’est donc a priori un nombre entier. On va introduire ici une notion plus g´en´erale, qui conduit `ades dimensions parfois non enti`eres. Objet de dimension 1 ×3 ×31 Par une homoth´etie de rapport 3, la mesure (longueur) est multipli´ee par 3 = 31, l’objet r´esultant contient 3 fois l’objet initial. La dimension d’un segment est 1. Jean-Pierre Demailly, Lyc´ee Champollion - Grenoble Ensembles fractals, mesure et dimension Dimension 2 ... Objet de dimension 2 ×3 ×32 Par une homoth´etie de rapport 3, la mesure (aire) de l’objet est multipli´ee par 9 = 32, l’objet r´esultant contient 9 fois l’objet initial. La dimension du carr´eest 2. Jean-Pierre Demailly, Lyc´ee Champollion - Grenoble Ensembles fractals, mesure et dimension Dimension d ≥ 3 .. -
Multiple Periodic Solutions and Fractal Attractors of Differential Equations with N-Valued Impulses
mathematics Article Multiple Periodic Solutions and Fractal Attractors of Differential Equations with n-Valued Impulses Jan Andres Department of Mathematical Analysis and Applications of Mathematics, Faculty of Science, Palacký University, 17. listopadu 12, 771 46 Olomouc, Czech Republic; [email protected] Received: 10 September 2020; Accepted: 30 September 2020; Published: 3 October 2020 Abstract: Ordinary differential equations with n-valued impulses are examined via the associated Poincaré translation operators from three perspectives: (i) the lower estimate of the number of periodic solutions on the compact subsets of Euclidean spaces and, in particular, on tori; (ii) weakly locally stable (i.e., non-ejective in the sense of Browder) invariant sets; (iii) fractal attractors determined implicitly by the generating vector fields, jointly with Devaney’s chaos on these attractors of the related shift dynamical systems. For (i), the multiplicity criteria can be effectively expressed in terms of the Nielsen numbers of the impulsive maps. For (ii) and (iii), the invariant sets and attractors can be obtained as the fixed points of topologically conjugated operators to induced impulsive maps in the hyperspaces of the compact subsets of the original basic spaces, endowed with the Hausdorff metric. Five illustrative examples of the main theorems are supplied about multiple periodic solutions (Examples 1–3) and fractal attractors (Examples 4 and 5). Keywords: impulsive differential equations; n-valued maps; Hutchinson-Barnsley operators; multiple periodic solutions; topological fractals; Devaney’s chaos on attractors; Poincaré operators; Nielsen number MSC: 28A20; 34B37; 34C28; Secondary 34C25; 37C25; 58C06 1. Introduction The theory of impulsive differential equations and inclusions has been systematically developed (see e.g., the monographs [1–4], and the references therein), among other things, especially because of many practical applications (see e.g., References [1,4–11]).