This textbook offers an introduction to the theory of Drinfeld modules, mathematical objects that are fundamental to modern number theory.

This textbook originates from a course taught by the late Ken Ireland in 1972. Designed to explore the theoretical underpinnings of undergraduate mathematics, the course focused on interrelationships and hands-on experience. Readers of this textbook will be taken on a modern rendering of Ireland’s path of discovery, consisting of excursions into number theory, algebra, and analysis. Replete with surprising connections, deep insights, and brilliantly curated invitations to try problems at just the right moment, this journey weaves a rich body of knowledge that is ideal for those going on to study or teach mathematics.

This volume examines some recent advances in inverse problems, new aspects of their mathematical modeling of inverse problems regarding in relation to their applications in physical systems and used the computational methods used.

Dieses Buch behandelt ausführlich die klassischen Themenstränge, die den Algebraunterricht durchziehen: Variablen – Terme – Funktionen – Gleichungen. Für diese Themen werden jeweils die fachlichen und didaktischen Grundlagen dargestellt, es werden zentrale didaktische Handlungsfelder identifiziert und unterrichtspraktische Überlegungen anhand vieler inner- und außermathematischer Beispiele aufgezeigt. Im Vordergrund steht dabei die Entwicklung eines tragfähigen Verständnisses grundlegender Begriffe in diesen vier Themensträngen. Darüber hinaus wird analysiert, wie algebraisches Denken und der verständige Umgang mit der Formelsprache so entwickelt werden kann, dass Lernende befähigt werden, für Phänomene ihrer Lebenswelt einen spezifisch mathematischen Zugang gewinnen zu können.

The Curves The Point of View of Max Noether Probably the oldest references to the problem of resolution of singularities are found in Max Noether's works on plane curves [cf. [148], [149]]. And probably the origin of the problem was to have a formula to compute the genus of a plane curve. The genus is the most useful birational invariant of a curve in classical projective geometry. It was long known that, for a plane curve of degree n having l m ordinary singular points with respective multiplicities ri, i E {1, . . . , m}, the genus p of the curve is given by the formula = (n - l)(n - 2) _ ~ "r. (r. _ 1) P 2 2 L. . ,. •• . Of course, the problem now arises: how to compute the genus of a plane curve having some non-ordinary singularities. This leads to the natural question: can we birationally transform any (singular) plane curve into another one having only ordinary singularities? The answer is positive. Let us give a flavor (without proofs) 2 on how Noether did it • To solve the problem, it is enough to consider a special kind of Cremona trans­ formations, namely quadratic transformations of the projective plane. Let ~ be a linear system of conics with three non-collinear base points r = {Ao, AI, A }, 2 and take a projective frame of the type {Ao, AI, A ; U}.