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2 Variational Problems with Fixed Boundaries
Prussian Academy of Sciences in 1831, was also a member of the French Academy
of Sciences and a member of the Royal Society (1855). Was one of the founders
of analytic number theory, founded the general theory of algebra unit elements
of. In terms of mathematical analysis, explained exactly the concept of conditionally convergent series for the first time, proved the possibility that the piecewise
continuous monotone function was expanded into the Fourier series. The works had
Sur la convergence des séries trigonométriques (1829), Über die Darstellung ganz
willkürlicher Functionen durch Sinus-und Cosinusreihen (1837) and Vorlesungen
über Zahlentheorie (1863) etc. Proposed the Dirichlet function, Dirichlet integral
and Dirichlet principle etc. There were also some research achievements to potential
theory, thermology, electromagnetics and mathematical physics etc.
Hadamard (Jacques Salomon, 1865.12.8–1963.10.17) French mathematician. Born
in Versailles, died in Paris. Entered the École Normale Supérieure de Paris to study
in 1888, received a doctor’s degree in 1892. Had served as a professor of the Collège
de France (1897–1935), Sorbonne University (1900–1912), École Polytechnique
(1912–1935) and École Centrale des Arts et Manufactures de Paris (1920–1935).
Was a member of the scientific institutions in many countries and honorary doctor
of many universities. Was elected a member of French Academy of Sciences in
1912, became a foreign academician of the Soviet Academy of Sciences in 1929.
Had given lectures in Tsinghua University for 3 months in 1936. All made contributions in function theory, number theory, theory of differential equations, functional analysis, differential geometry, set theory and mathematical foundation etc.
aspects. Obtained the Legion of Honour at the age of 90. The works had Leçons de
géométrie élémentaire (1898), Leçons sur la propagation des ondes et les équations
de l’hydrodynamique (1903), Leçons sur le calcul des variations (1910), Essai sur
la psychologie de l’invention dans le domaine mathématique (1959) and La théorie
des équations aux dérivées partielles (1964) etc.
Fredholm (Erik Ivar, 1866.4.7–1927.8.17) Swedish mathematician. Born and died in
Stockholm. Since 1885 successively studied at the Kungliga Tekniska högskolan de
Stockholm, Uppsala University and Stockholm University, under the supervision of
Mittag-Leffler (Magnus Gustaf, 1846.3.16–1927.7.7), obtained his PhD at Uppsala
University in 1898. After graduation was a docent at Stockholm University, became
a professor from 1906 until his death. Was academician of the Swedish Academy
of Sciences and Communication academician of French Academy of Sciences, and
won the award of Paris Academy of Sciences. The main contribution was in terms of
integral equation, the founder of general theory of integral equation. researched three
kinds of important integral equations, proposed two theorems and their solutions,
later the three kinds of integral equations is called the Fredholm’s integral equation
of the first, second, third kind, and the studies about the solutions of Fredholm integral
equations are called the Fredholm theory. The research achievements had led to the
emergence and development of Hilbert space and other function spaces. Also made
some contributions in a power series theory. The works had Sur une nouvelle méthode
pour la résolution du problème de Dirichlet (1900), Sur une classe d’équations
fonctionnelles (1903) and Oeuvres complètes (1955).
2 Variational Problems with Fixed Boundaries
Prussian Academy of Sciences in 1831, was also a member of the French Academy
of Sciences and a member of the Royal Society (1855). Was one of the founders
of analytic number theory, founded the general theory of algebra unit elements
of. In terms of mathematical analysis, explained exactly the concept of conditionally convergent series for the first time, proved the possibility that the piecewise
continuous monotone function was expanded into the Fourier series. The works had
Sur la convergence des séries trigonométriques (1829), Über die Darstellung ganz
willkürlicher Functionen durch Sinus-und Cosinusreihen (1837) and Vorlesungen
über Zahlentheorie (1863) etc. Proposed the Dirichlet function, Dirichlet integral
and Dirichlet principle etc. There were also some research achievements to potential
theory, thermology, electromagnetics and mathematical physics etc.
Hadamard (Jacques Salomon, 1865.12.8–1963.10.17) French mathematician. Born
in Versailles, died in Paris. Entered the École Normale Supérieure de Paris to study
in 1888, received a doctor’s degree in 1892. Had served as a professor of the Collège
de France (1897–1935), Sorbonne University (1900–1912), École Polytechnique
(1912–1935) and École Centrale des Arts et Manufactures de Paris (1920–1935).
Was a member of the scientific institutions in many countries and honorary doctor
of many universities. Was elected a member of French Academy of Sciences in
1912, became a foreign academician of the Soviet Academy of Sciences in 1929.
Had given lectures in Tsinghua University for 3 months in 1936. All made contributions in function theory, number theory, theory of differential equations, functional analysis, differential geometry, set theory and mathematical foundation etc.
aspects. Obtained the Legion of Honour at the age of 90. The works had Leçons de
géométrie élémentaire (1898), Leçons sur la propagation des ondes et les équations
de l’hydrodynamique (1903), Leçons sur le calcul des variations (1910), Essai sur
la psychologie de l’invention dans le domaine mathématique (1959) and La théorie
des équations aux dérivées partielles (1964) etc.
Fredholm (Erik Ivar, 1866.4.7–1927.8.17) Swedish mathematician. Born and died in
Stockholm. Since 1885 successively studied at the Kungliga Tekniska högskolan de
Stockholm, Uppsala University and Stockholm University, under the supervision of
Mittag-Leffler (Magnus Gustaf, 1846.3.16–1927.7.7), obtained his PhD at Uppsala
University in 1898. After graduation was a docent at Stockholm University, became
a professor from 1906 until his death. Was academician of the Swedish Academy
of Sciences and Communication academician of French Academy of Sciences, and
won the award of Paris Academy of Sciences. The main contribution was in terms of
integral equation, the founder of general theory of integral equation. researched three
kinds of important integral equations, proposed two theorems and their solutions,
later the three kinds of integral equations is called the Fredholm’s integral equation
of the first, second, third kind, and the studies about the solutions of Fredholm integral
equations are called the Fredholm theory. The research achievements had led to the
emergence and development of Hilbert space and other function spaces. Also made
some contributions in a power series theory. The works had Sur une nouvelle méthode
pour la résolution du problème de Dirichlet (1900), Sur une classe d’équations
fonctionnelles (1903) and Oeuvres complètes (1955).