Linear Partial Differential Equations: Fundamental Solutions, Hypoellipticity, Local Existence
Overview
This entry contains an introduction to the theory of linear partial differential equations. We introduce the notion of fundamental solution for the case with constant coefficients and sketch the proof of the fact that any nontrivial operator of this type has one. We show some applications of fundamental solutions to the study of existence and regularity of solutions of linear partial differential operators with constant coefficients. Then we construct fundamental solutions for the basic operators of mathematical physics. We conclude with the celebrated Lewy’s counterexample, showing that the local existence theory, which is available for operators with constant coefficients, does not hold if the coefficients are allowed to be variable.
This entry is just a short introduction to a highly developed subject. For more detailed expositions, we refer to [1, 2, 4, 7, 8, 11, 13, 14].
Basic Notations
References
- 1.Chazarain J, Piriou A (1981) Introduction à la théorie des équations aux dérivées partielles linéaires. Gauthier-Villars, ParisMATHGoogle Scholar
- 2.Evans LC (2010) Partial differential equations, 2nd edn. American Mathematical Society, ProvidenceMATHGoogle Scholar
- 3.Feynman R, Leighton R, Sands M (1966) The Feynman lectures in physics, vol II. Addison-Wesley, ReadingGoogle Scholar
- 4.Folland G (1995) Introduction to partial differential equations. Princeton University Press, PrincetonMATHGoogle Scholar
- 5.Guidetti D, Distributions, Encyclopedia of thermal stresses.Google Scholar
- 6.Guidetti D, Operations on distributions, Encyclopedia of thermal stresses.Google Scholar
- 7.Hörmander L (1963) Linear partial differential operators. Springer, BerlinMATHGoogle Scholar
- 8.Hörmander L (1990) The analysis of linear partial differential operators I. Springer, BerlinMATHGoogle Scholar
- 9.Lewy H (1957) An example of a smooth linear partial differential equation without solutions. Ann Math, Princeton 66:155–158MathSciNetGoogle Scholar
- 10.Shankar R (1994) Principles of quantum mechanics, 2nd edn. Kluwer Academic/Plenum, New YorkMATHGoogle Scholar
- 11.Szmydt Z (1977) Fourier transformation and linear differential equations. Reidel Publishing, DordrechtMATHGoogle Scholar
- 12.Treves F (1967) Topological vector spaces, distributions and kernels. Academic, San DiegoMATHGoogle Scholar
- 13.Treves F (1975) Basic linear partial differential equations. Academic, New YorkMATHGoogle Scholar
- 14.Vladimirov VS (1971) Equations of mathematical physics. Marcel Dekker, New YorkGoogle Scholar