analysis

Table of Contents

Introduction
Historical background
- Bridging the gap between arithmetic and geometry
- Discovery of the calculus and the search for foundations
Technical preliminaries
- Numbers and functions
  - Number systems
  - Functions
- The problem of continuity
  - Approximations in geometry
  - Infinite series
  - The limit of a sequence
  - Continuity of functions
- Properties of the real numbers
Calculus
- Differentiation
  - Average rates of change
  - Instantaneous rates of change
  - Formal definition of the derivative
  - Graphical interpretation
  - Higher-order derivatives
- Integration
  - The fundamental theorem of calculus
  - Antidifferentiation
  - The Riemann integral
Ordinary differential equations
- Newton and differential equations
  - Newton’s laws of motion
  - Exponential growth and decay
- Dynamical systems theory and chaos
Partial differential equations
- Musical origins
  - Harmony
  - Normal modes
  - Partial derivatives
    - D’Alembert’s wave equation
    - Trigonometric series solutions
- Fourier analysis
Complex analysis
- Formal definition of complex numbers
- Extension of analytic concepts to complex numbers
- Some key ideas of complex analysis
Measure theory
Other areas of analysis
- Functional analysis
- Variational principles and global analysis
- Constructive analysis
- Nonstandard analysis
History of analysis
- The Greeks encounter continuous magnitudes
  - The Pythagoreans and irrational numbers
  - Zeno’s paradoxes and the concept of motion
  - The method of exhaustion
- Models of motion in medieval Europe
- Analytic geometry
- The fundamental theorem of calculus
  - Differentials and integrals
  - Discovery of the theorem
  - Calculus flourishes
- Elaboration and generalization
  - Euler and infinite series
  - Complex exponentials
  - Functions
  - Fluid flow
- Rebuilding the foundations
  - Arithmetization of analysis
  - Analysis in higher dimensions

References & Edit History Related Topics

Images

The transformation of a circular region into an approximately rectangular regionThis suggests that the same constant (π) appears in the formula for the circumference, 2πr, and in the formula for the area, πr2. As the number of pieces increases (from left to right), the “rectangle” converges on a πr by r rectangle with area πr2—the same area as that of the circle. This method of approximating a (complex) region by dividing it into simpler regions dates from antiquity and reappears in the calculus.

Graphical illustration of an infinite geometric seriesClearly, the sum of the square's parts (12, 14, 18, etc.) is 1 (square). Thus, it can be seen that 1 is the limit of this series—that is, the value to which the partial sums converge.

Graph of distance traveled versus time elapsed for the motion of an automobileBecause the speed of the automobile is constant in this example (50 kilometres per hour), the graph is a straight line.

Graph of a functionPart A illustrates the general idea of graphing any function: choose a value for the independent variable, t, calculate the corresponding value for f(t), and repeat this process until the general shape of the graph is apparent. (In practice, various techniques are available to reduce the number of values needed to determine the graph's basic shape.) In part B a specific function, the parabola f(t) = t2, is graphed for further illustration.

An illustration of the difference between average and instantaneous rates of changeThe graph of f(t) shows the secant between (t, f(t)) and (t + h, f(t + h)) and the tangent to f(t) at t. As the time interval h approaches zero, the secant (average speed) approaches the tangent (actual, or instantaneous, speed) at (t, f(t)).

A curve sketched with the help of calculusThis graph of f(x) = x3 − 3x + 2 illustrates the essential steps in constructing a graph. The local maximum (at x = − 1) and the local minimum (at x = 1) are first plotted. Then a value for x is chosen from each of the three resulting ranges, x < −1, −1 < x < 1, and 1 < x, to suggest the general shape of the curve. Further values for x may be chosen to produce a more accurate graph.

Integral region graphThe shaded region, bounded by the vertical lines t = a, t = b, the t-axis, and the graph of f, is denoted by a bf(t)dt. Finding the areas of irregular regions was one of the motivations for the discovery of the calculus.

fundamental theorem of calculus

The Riemann integralIf the shaded areas in B (using inscribed rectangles) and C (using circumscribed rectangles) converge to the same value for their total areas, the common value to which they converge is defined as the Riemann integral of A.

A Poincaré section, or mapThe trajectory, or orbit, of an object x is sampled periodically, as indicated by the blue disk. The rate of change for the object is determined for each intersection of its orbit with the disk, as shown by P(x) and P2(x). This set of values can then be used to analyze the long-term stability of the system. For contrast, note the perfectly periodic orbit of the point o, as indicated by o = P(o).

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Photos

The transformation of a circular region into an approximately rectangular regionThis suggests that the same constant (π) appears in the formula for the circumference, 2πr, and in the formula for the area, πr2. As the number of pieces increases (from left to right), the “rectangle” converges on a πr by r rectangle with area πr2—the same area as that of the circle. This method of approximating a (complex) region by dividing it into simpler regions dates from antiquity and reappears in the calculus.

Graphical illustration of an infinite geometric seriesClearly, the sum of the square's parts (12, 14, 18, etc.) is 1 (square). Thus, it can be seen that 1 is the limit of this series—that is, the value to which the partial sums converge.

Graph of distance traveled versus time elapsed for the motion of an automobileBecause the speed of the automobile is constant in this example (50 kilometres per hour), the graph is a straight line.

Graph of a functionPart A illustrates the general idea of graphing any function: choose a value for the independent variable, t, calculate the corresponding value for f(t), and repeat this process until the general shape of the graph is apparent. (In practice, various techniques are available to reduce the number of values needed to determine the graph's basic shape.) In part B a specific function, the parabola f(t) = t2, is graphed for further illustration.

An illustration of the difference between average and instantaneous rates of changeThe graph of f(t) shows the secant between (t, f(t)) and (t + h, f(t + h)) and the tangent to f(t) at t. As the time interval h approaches zero, the secant (average speed) approaches the tangent (actual, or instantaneous, speed) at (t, f(t)).

A curve sketched with the help of calculusThis graph of f(x) = x3 − 3x + 2 illustrates the essential steps in constructing a graph. The local maximum (at x = − 1) and the local minimum (at x = 1) are first plotted. Then a value for x is chosen from each of the three resulting ranges, x < −1, −1 < x < 1, and 1 < x, to suggest the general shape of the curve. Further values for x may be chosen to produce a more accurate graph.

Integral region graphThe shaded region, bounded by the vertical lines t = a, t = b, the t-axis, and the graph of f, is denoted by a bf(t)dt. Finding the areas of irregular regions was one of the motivations for the discovery of the calculus.

fundamental theorem of calculus

The Riemann integralIf the shaded areas in B (using inscribed rectangles) and C (using circumscribed rectangles) converge to the same value for their total areas, the common value to which they converge is defined as the Riemann integral of A.

A Poincaré section, or mapThe trajectory, or orbit, of an object x is sampled periodically, as indicated by the blue disk. The rate of change for the object is determined for each intersection of its orbit with the disk, as shown by P(x) and P2(x). This set of values can then be used to analyze the long-term stability of the system. For contrast, note the perfectly periodic orbit of the point o, as indicated by o = P(o).

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Topics

vector analysis tensor analysis calculus of variations harmonic analysis mean-value theorem Darboux’s theorem Rolle’s theorem Abel’s test functional analysis Dirichlet’s test cryptology computer science combinatorics algebra statistics geometry set theory information theory trigonometry optimization

Key People

Henri Poincaré, 1909.

Henri Poincaré

French mathematician

Bernhard Riemann, lithograph after a portrait, artist unknown, 1863.

Bernhard Riemann

German mathematician

Leonhard Euler

Leonhard Euler

Swiss mathematician

Norbert Wiener.

Norbert Wiener

American mathematician

Joseph Fourier

Joseph Fourier

French mathematician

Adrien-Marie Legendre

French mathematician

Augustin-Louis Cauchy

French mathematician

Joseph Liouville

French mathematician

Karl Weierstrass, engraving after a photograph by Franz Kullrich.

Karl Weierstrass

German mathematician

Godfrey Hardy, 1941.

G.H. Hardy

English mathematician

Sir Edmund Taylor Whittaker

British mathematician

George David Birkhoff

American mathematician

Lebesgue, portrait by an unknown artist, 1929

Henri-Léon Lebesgue

French mathematician

Isadore Singer receiving the Abel Prize

Isadore Singer

American mathematician

Charles-Émile Picard.

Charles-Émile Picard

French mathematician

Edward Charles Titchmarsh

British mathematician

Charles-François Sturm, pencil sketch by Daniel Colladon, 1822; in the Academy of Sciences, Paris.

Charles-François Sturm

French-Swiss mathematician

Mittag-Leffler

Magnus Gösta Mittag-Leffler

Swedish mathematician

Laurent Lafforgue

French mathematician

Camille Jordan

French mathematician

Quiz

Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.

Define It: Math Terms

Equations written on blackboard

Numbers and Mathematics