Complex differential equation

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A complex differential equation (CDE) is a differential equation whose solutions are functions of a complex variable.

Contents

Constructing integrals involves choice of what path to take, which means singularities and branch points of the equation need to be studied. Analytic continuation is used to generate new solutions and this means topological considerations such as monodromy, coverings and connectedness are to be taken into account.

Existence and uniqueness theorems involve the use of majorants and minorants.

Study of rational second order ODEs in the complex plane led to the discovery of new transcendental special functions, which are now known as Painlevé transcendents.

Nevanlinna theory can be used to study complex differential equations. This leads to extensions of Malmquist's theorem. [1]

Generalizations

Generalizations include partial differential equations in several complex variables, or differential equations on complex manifolds. [2] Also there are at least a couple of ways of studying complex difference equations: either study holomorphic functions [3] which satisfy functional relations given by the difference equation or study discrete analogs [4] of holomorphicity such as monodiffric functions. Also integral equations can be studied in the complex domain. [5]

History

Some of the early contributors to the theory of complex differential equations include:

See also

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Steven G. Krantz American mathematician

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References

  1. Eremenko, A. (1982). "Meromorphic solutions of algebraic differential equations" (PDF). Russian Mathematical Surveys. 37 (4): 61–94. CiteSeerX   10.1.1.139.8499 . doi:10.1070/RM1982v037n04ABEH003967.
  2. So-Chin Chen; Mei-Chi Shaw (2002). Partial Differential Equations in Several Complex Variables. American Mathematical Society. ISBN   978-0-8218-2961-5.
  3. Complex Difference Equations of Malmquist Type Archived 2005-08-25 at the Wayback Machine
  4. An Introduction to complex functions on product of two time scales
  5. Analytic solutions to integral equations in the complex domain

Further reading