This is fertile new ground for computer experimentation in, among other topics, geometry, combinatorics, probability, numerical approximation, and discrete complex analysis. This is not our main topic, and we concentrate on some aspects only that we need later. In this paper we start with briey surveying two related topics. The theory of discrete analytic functions by phillip l. The experimental analysis is usually applied to the problem. The idea now fact is that discrete analytic functions maps between circle packings preserving the structure of tangents and orientation can be used to approximate classical conformal maps. The theory of discrete analytic functions, by kenneth stephenson, cambridge university press, cambridge uk, 2005, pp. With its clear presentation, the text shows students how to present cases logically beyond this course. He began contributing to the development of circle packing and its associated discrete conformal geometry through publications and software, culminating in his 2005 book, introduction to circle packing. Holomorphic functions are conformal, mapping in nitesimal circles to in nitesimal circles.
We will see the details shortly, but assuming you have run scookiesand have this example before you on the computer, try clicking the left mouse button on some circle in one packing. In this chapter, we address this issue for continuous analytic functions. Applications are given in information theory, statistical physics, graph algorithms and quantum physics. Introduction to circle packing the theory of discrete analytic functions. The theory of discrete analytic functions kindle edition by stephenson, kenneth. Introduction thurstons circle packing is a discrete analogue of holomorphic functions 20. Introduction to circle packing the theory of discrete analytic functions pdf unaescovedo. To obtain a 1dimensional packing density, distribution of the minimum of gaps, etc. Introduction to clinical methods in communication disorders pdf unaescovedo. A good guide to creating your own circle packings is cli. The descartes circle theorem if four circles forming a descartes con.
Since spring 20, the book has been used as the primary textbook or a supplemental resource at multiple universities around the world see the partial adoptions list. Thurston proposed regarding the map induced from two circle packings with the same combinatorial structure in the plane as a discrete holomorphic function. The theory of discrete analytic functions is a mathematical monograph concerning systems of tangent circles and the circle packing theorem. Section 1 of the chapter covers circle packing basics and introduces discrete analytic functions as maps between circle packings. A discrete introduction teaches students the fundamental concepts in discrete mathematics and proofwriting skills. Circle packings, as studied in this book, are systems of circles that touch at tangent points but do not. For example, galileo published his most famous books as dialogues between simplicio a rather. As this approximation theory developed, a second aspect that we will call discrete analytic function theory, began to emerge. Download it once and read it on your kindle device, pc, phones or tablets. Discrete conformal mappings via circle patterns 17 more generally, troyanov investigates the conditions under which one may prescribe isolated cone singularities and riemannian curvature, as a smooth function, on a riemann surface. This book lays out their study, from first definitions to latest theory, computations, and applications. Introduction circle packing theory discrete analytic functions. The author gratefully acknowledges support of the national science foundation and the ten.
Stephenson, cambridge university press, cambridge, 2005. A circle packing is nothing more than a collection of circles with prescribed tangencies that lie on a surface. Discrete analytic functions accessscience from mcgraw. The topic of circle packing was born of the computer age but takes its inspiration and themes from core areas of classical mathematics. This book introduces a new mathematical topic known as circle packing, taking the reader from first definitions to late. Circle packings are configurations of circles with specified patterns of tangency, and lend themselves naturally to computer experimentation and visualization. It was written by kenneth stephenson and published in 2005 by the cambridge university press. Maps between them display, with surprising faithfulness, many of the geometric properties associated with classical analytic functions.
This paper introduces the fundamentals of an emerging discrete analytic function theory and. The striking analogy between circle patterns and the classical analytic function theory is underlined by such facts as the uniformization theorem concerning circle packing realizations of. At its core, analyticity is a profoundly geometric property, and this comes out in the discrete. Discrete analytic functions accessscience from mcgrawhill. Ken stephenson has produced this textbook an effective and enjoyable tour of both the basic theory of circle parking and its use in deriving an intricate theory of discrete analytic functions. The theory of discrete analytic functions 9780521823562. Packing available for download and read online in other formats. To illustrate the method, new proofs are given to most of the results in 3,5. A central motivation behind thurstons popularization of circle packing was its role as a discrete analogue of conformal mapping. As this approximation theory developed, a second aspect that we will call discrete analytic function theory, began to. Kenneth stephenson, introduction to circle packing. Circle packing, blaschke products, discrete analytic functions. In particular, they raised a question about existence of branched circle packings and discrete versions of analytic functions with branch points. The packing density of the general multidimensional random sequential packing of cubes hypercubes makes a wellknown unsolved problem.
Instead of regular homework assignments, students will be assigned problems labeled. The theory of discrete analytic functions, cup, 2005 c. For pairs of lips to kiss maybe involves no trigonometry. Introduction circle packings are collections of circles in the plane with prescribed pat. Thurston, william 1985, the finite riemann mapping theorem, invited talk at the international symposium at purdue university on the occasion of the proof of the bieberbach conjecture. The theory of discrete analytic functions by kenneth stephenson description. The evolution of mathematics david coulson, 2016 2.
Circle patterns with the combinatorics of the square grid were introduced in ref. Thurston suggested applying circle packings to obtain approximations to riemann mappings. Stephenson, ken 2005, introduction to circle packing, the theory of discrete analytic functions, cambridge. The theory of discrete analytic functions kenneth stephenson frontmatter more information. In the past, books about science and math were written in many different styles. In the present paper a formal power series approach to the theory of discrete analytic functions is given which it is hoped not only gives new insight to the theory but also makes many proofs much simpler and shorter. Discrete analytic functions, also known as circlepacking maps, are mappings between circle packings whose properties faithfully reflect the properties that are characteristic of classical analytic functions. Explorations in complex analysis mathematical association. In the present paper, we show that in some precise sense the former is. E is planar, if it can be drawn in the plane so that its edges are jordan curves and they intersect only at their endnodes1. Discrete analytic functions, also known as circle packing maps, are mappings between circle packings whose properties faithfully reflect the properties that are characteristic of classical analytic functions.
Pdf linear and nonlinear theories of discrete analytic. Introduction to circle packing the topic of circle packing was born of the computer age but takes its inspiration and themes from core areas of classical mathematics. The theory of discrete analytic functions kenneth stephenson the topic of circle packing was born of the computer age but takes its inspiration and themes from core areas of classical mathematics. Hexagonal circle patterns with constant intersection angles. The theory of discrete analytic functions, by kenneth stephenson, cup, 2005.
This gave rise to the development of a theory of discrete analytic functions, which is a new tool in conformal geometry that can be used to implement many of the classical tools from complex analysis. Hexagonal circle patterns with constant intersection. All of the material is directly applicable to computer science and engineering, but it is presented from a mathematicians. Circle packing and discrete analytic function theory.
This book surveys a number of such connections between graph theory and geometry. This paper introduces the fundamentals of an emerging discrete analytic function. Ams transactions of the american mathematical society. Connections to many other subjects were made, including crystallography, the local theory of banach spaces, and. An open introduction is a free, open source textbook appropriate for a first or second year undergraduate course for math majors, especially those who will go on to teach. The theory of discrete analytic functions find, read and cite all. This paper opens a program about the study of the deformations of discrete metrics and discrete curvatures. Introduction to circle packing, cambridge university press, cambridge, 2005. A circle packing is a configuration of circles having a specified pattern of tangencies, as introduced by william thurston in 1985.
We also use this phrase to denote the image of this embedding, i. T his book describes the rich math matics associated with patterns of angent circles in twodimensional surfaces. In geometry, circle packing is the study of the arrangement of circles of equal or varying sizes on a given surface such that no overlapping occurs and so that all circles touch another. Use features like bookmarks, note taking and highlighting while reading introduction to circle packing. A new approach to the theory of discrete analytic functions. It was written by kenneth stephenson and published in 2005 by the cambridge university press topics. This conjecture was proven by rodin and sullivan rs, and many additional connections with analytic functions have emerged since then. In this way we may, for instance, approximate the map ensured by the riemann mapping theorem which is not dened. Our main focus is optimization algorithms for the creation of cp meshes and to derive from them geometric structures relevant to architectural geometry. Tis not so when four circles kiss each one the other three. The theory of discrete analytic functions, by kenneth.
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