Aktentasche Vintage Pergament -

Python-Handtasche aus den 1940er Jahren. Das Modell ist ein Klassiker mit zeitloser Eleganz: Es bleibt nicht unbemerkt und kommt nie aus der Mode. Die Bedingungen sind gut; Kleine Unvollkommenheiten im Leder sind der Zeit geschuldet.

Tasche von Cesare Piccini, wahrscheinlich in den 1960er Jahren entworfen. Brauner Samt mit gelben und schwarzen Bändern. Samtbrauner Griff. Der Stahlring kann gezogen werden, um den Riegel zu öffnen. Der Spiegel in der Tasche ist in der Tasche eingebettet. Sehr guter Zustand, das Leder in der Tasche ist leicht markiert. Entworfen in Italien.

Simon Kirwan Donaldson, S. K. Donaldson, P. B. Kronheimer
Clarendon Press

This book provides the first lucid and accessible account to the modern study of the geometry of four-manifolds. It has become required reading for postgraduates and research workers whose research touches on this topic. Pre-requisites are a firm grounding in differential topology, andgeometry as may be gained from the first year of a graduate course. The subject matter of this book is the most significant breakthrough in mathematics of the last fifty years, and Professor Donaldson won a Fields medal for his work in the area. The authors start from the standpoint that thefundamental group and intersection form of a four-manifold provides information about its homology and characteristic classes, but little of its differential topology. It turns out that the classification up to diffeomorphism of four-manifolds is very different from the classification of unimodularforms and that the study of this question leads naturally to the new Donaldson invariants of four-manifolds. A central theme of this book is that the appropriate geometrical tools for investigating these questions come from mathematical physics: the Yang-Mills theory and anti-self dual connectionsover four-manifolds. One of the many consquences of this theory is that 'exotic' smooth manifolds exist which are homeomorphic but not diffeomorphic to (4, and that large classes of forms cannot be realized as intersection forms whereas distinct manifolds may share the same form. These result havehad far-reaching consequences in algebraic geometry, topology, and mathematical physics, and will continue to be a mainspring of mathematical research for years to come.