Algebraic Theory of Locally Nilpotent Derivations (Encyclopaedia of Mathematical Sciences Book 136)

This book explores the theory and application of locally nilpotent derivations. It provides a unified treatment of the subject, beginning with sixteen First Principles on which the entire theory is based. These are used to establish classical results, such as Rentschler’s Theorem for the plane, right up to the most recent results, such as Makar-Limanov’s Theorem for locally nilpotent derivations of polynomial rings. The book also includes a wealth of pexamples and open problems. But, in the further development of a branch of mathematics, the human mind, encouraged by the success of its solutions, becomes conscious of its independence. It evolves from itself alone, often without appreciable in?uence from without, by means of logical combination, generalization, specialization, by separating and collecting ideas in fortunate new ways, new and fruitful problems, and appears then itself as the real questioner. David Hilbert, Mathematical Problems Thestudyoflocallynipotentderivationsand G -actionshasrecentlyemerged a from the long shadows of other branches of mathematics, branches whose provenance is older and more distinguished. The subject grew out of the rich environment of Lie theory, invariant theory, and di?erential equations, and continues to draw inspiration from these and other ?elds. At the heart of the present exposition lie sixteen principles for locally nilpotent derivations, laid out in Chapter 1. These provide the foundation upon which the subsequent theory is built. As a rule, we would like to dist- guish which properties of a locally nilpotent derivation are due to its being a “derivation”, and which are special to the condition “locally nilpotent”. Thus, we ?rst consider general properties of derivations. The sixteen First Principles which follow can then be seen as belonging especially to the locally nilpotent derivations. This book explores the theory and application of locally nilpotent derivations, which is a subject of growing interest and importance not only among those in commutative algebra and algebraic geometry, but also in fields such as Lie algebras and differential equations. The author provides a unified treatment of the subject, beginning with 16 First Principles on which the entire theory is based. These are used to establish classical results, such as Rentschler's Theorem for the plane, right up to the most recent results, such as Makar-Limanov's Theorem for locally nilpotent derivations of polynomial rings. Topics of special interest include: progress in the dimension three case, finiteness questions (Hilbert's 14th Problem), algorithms, the Makar-Limanov invariant, and connections to the Cancellation Problem and the Embedding Problem. The reader will also find a wealth of pertinent examples and open problems and an up-to-date resource for research. The study of locally nipotent derivations and Ga-actions has recently emerged from the long shadows of other branches of mathematics, branches whose provenance is older and more distinguished.