springer basel birkhäuser basel birkhäuser jul 2000 (3 risultati)

Buch. Condizione: Neu. This item is printed on demand - it takes 3-4 days longer - Neuware -A beautiful interplay between probability theory (Markov processes, martingale theory) on the one hand and operator and spectral theory on the other yields a uniform treatment of several kinds of Hamiltonians such as the Laplace operator, relativistic Hamiltonian, Laplace-Beltrami operator, and generators of Ornstein-Uhlenbeck processes. For such operators regular and singular perturbations of order zero and their spectral properties are investigated.A complete treatment of the Feynman-Kac formula is given. The theory is applied to such topics as compactness or trace class properties of differences of Feynman-Kac semigroups, preservation of absolutely continuous and/or essential spectra and completeness of scattering systems.The unified approach provides a new viewpoint of and a deeper insight into the subject. The book is aimed at advanced students and researchers in mathematical physics and mathematics with an interest in quantum physics, scattering theory, heat equation, operator theory, probability theory and spectral theory. 463 pp. Englisch.

Buch. Condizione: Neu. This item is printed on demand - it takes 3-4 days longer - Neuware -The aim of this book is to present recently discovered connections between Artin's braid groups En and left self-distributive systems (also called LD systems), which are sets equipped with a binary operation satisfying the left self-distributivity identity x(yz) = (xy)(xz). (LD) Such connections appeared in set theory in the 1980s and led to the discovery in 1991 of a left invariant linear order on the braid groups. Braids and self-distributivity have been studied for a long time. Braid groups were introduced in the 1930s by E. Artin, and they have played an increas ing role in mathematics in view of their connection with many fields, such as knot theory, algebraic combinatorics, quantum groups and the Yang-Baxter equation, etc. LD-systems have also been considered for several decades: early examples are mentioned in the beginning of the 20th century, and the first general results can be traced back to Belousov in the 1960s. The existence of a connection between braids and left self-distributivity has been observed and used in low dimensional topology for more than twenty years, in particular in work by Joyce, Brieskorn, Kauffman and their students. Brieskorn mentions that the connection is already implicit in (Hurwitz 1891). The results we shall concentrate on here rely on a new approach developed in the late 1980s and originating from set theory. 623 pp. Englisch.

Buch. Condizione: Neu. This item is printed on demand - it takes 3-4 days longer - Neuware -Extending the range of enzymatic catalysis by using non-aqueous media has now developed into a powerful approach in biochemistry and biotechnology. One peculiar feature which distinguishes it from the conventional enzymology (carried out in aqueous buffers) is that the awareness of different parameters that control and influence the behaviour of enzymes in such environments has emerged rather slowly. Science is about being able to repeat what somebody else has done. Absence of knowledge about such well-defined parameters/fac tors has sometimes made some workers rather cautious and diffident about using this approach in their laboratories. But for this, non-aqueous enzymol ogy would be more widely practised. It is these thoughts that made me feel that the availability of some well-defined protocols for various applications invol ving enzymes in non-aqueous environments would further catalyze the growth of this area. Hence this book, in which each chapter has some protocols in a specific area. The protocols are preceded by brief background material. The early chapters, which are of general importance, concern control of water ac tivity and stabilization via immobilization. Some subsequent chapters provide the protocols for transformations involving lipids and carbohydrates, peptide synthesis, and preparation of chiral compounds. The disproportionate focus on lipases is not a coincidence; this class of enzymes has been used more often than others in non-aqueous enzymology. 218 pp. Englisch.