Jaroslav Zamastil – författare

The book is about the transition from classical to quantum mechanics, covering the historical development of this great leap, and explaining the concepts needed to understand it at a level suitable for undergraduate students. The first part of the book summarizes classical electrodynamics and the Hamiltonian formulation of classical mechanics, the two elements of classical physics which are crucial for understanding the classical to quantum transition. The second part loosely traces the historical development of the classical to quantum transition, starting with Einstein’s 1916 derivation of the Planck radiation law, continuing with the Ladenburg-Kramers-Born-Heisenberg dispersion theory and ending with Heisenberg’s magical 1925 paper which established quantum mechanics. The purpose of the book is partly historical, partly philosophical, but mainly pedagogical. It will appeal to a wide audience, from undergraduate students, for whom it can serve as a preparatory or supplementary text to standard textbooks, to physicists and historians interested in the historical development of science.

This book presents an algebraic approach to the coupled cluster method for many-electron systems, pioneered by Josef Paldus. Using field methods along with an algebraic, rather than diagrammatic, approach facilitates a way of deriving the coupled cluster method which is readily understandable at the graduate level. The book begins with the notion of the quantized electron field and shows how the N-electron Hamiltonian can be expressed in its language. This is followed by introduction of the Fermi vacuum and derivation of the Hartree-Fock equations along with conditions for stability of their solutions. Following this groundwork, the book discusses a method of configuration interaction to account for dynamical correlations between electrons, pointing out the size-extensivity problem, and showing how this problem is solved with the coupled cluster approach. This is followed by derivation of the coupled cluster equations in spin-orbital form. Finally, the book explores practical aspects, showing how one may take advantage of permutational and spin symmetries, and how to solve coupled-cluster equations, illustrated by the Hubbard model of benzene, the simplest quasi-realistic model of electron correlation.

This book highlights the power and elegance of algebraic methods of solving problems in quantum mechanics. It shows that symmetries not only provide elegant solutions to problems that can be solved exactly, but also substantially simplify problems that must be solved approximately.

Furthermore, the book provides an elementary exposition of quantum electrodynamics and its application to low-energy physics, along with a thorough analysis of the role of relativistic, magnetic, and quantum electrodynamic effects in atomic spectroscopy. Included are essential derivations made clear through detailed, transparent calculations.