It would be hopeless to attempt to give a complete account of the history of the calculus of variations. The interest of Greek philosophers in isoperimetric problems underscores the importance of "optimal form" in ancient cultures, see Hildebrandt-Tromba [1] for a beautiful treatise of this subject. While variatioยญ nal problems thus are part of our classical cultural heritage, the first modern treatment of a variational problem is attributed to Fermat (see Goldstine [1; p.l]). Postulating that light follows a path of least possible time, in 1662 Ferยญ mat was able to derive the laws of refraction, thereby using methods which may already be termed analytic. With the development of the Calculus by Newton and Leibniz, the basis was laid for a more systematic development of the calculus of variations. The brothers Johann and Jakob Bernoulli and Johann's student Leonhard Euler, all from the city of Basel in Switzerland, were to become the "founding fathers" (Hildebrandt-Tromba [1; p.21]) of this new discipline. In 1743 Euler [1] subยญ mitted "A method for finding curves enjoying certain maximum or minimum properties", published 1744, the first textbook on the calculus of variations
CONTENT
I. The Direct Methods in the Calculus of Variations -- II. Minimax Methods -- III. Limit Cases of the Palais-Smale Condition -- Appendix A -- Sobolev Spaces -- Hรถlder Spaces -- Imbedding Theorems -- Density Theorem -- Trace and Extension Theorems -- Poincarรฉ Inequality -- Appendix B -- Schauder Estimates -- Weak Solutions -- A Regularity Result -- Maximum Principle -- Weak Maximum Principle -- Application -- Appendix C -- Frรฉchet Differentiability -- Natural Growth Conditions -- References
SUBJECT
Mathematics
Mathematical analysis
Analysis (Mathematics)
System theory
Calculus of variations
Statistical physics
Dynamical systems
Mathematics
Systems Theory
Control
Calculus of Variations and Optimal Control; Optimization