Ever since quantum field theory was actually invented in 1947 by Hans Albrecht Bethe, it has been a part of advanced physics studies. Quantum electrodynamics provides researchers with a framework to study the interaction of particles and radiation through mathematics.
“Quantum electrodynamics helps us see the world in a new light and then changes our perspective,” says Dr. Ulrich Jentschura, professor of physics at Missouri University of Science and Technology. “It deals with the very foundations of physics and connects aspects of research in a way that cannot otherwise be brought together for comparison.”
Jentschura covers the subject extensively in a new book titled Quantum electrodynamics: atoms, lasers and gravity published by World Scientific. Written alongside Dr. Gregory Adkins, William G. and Elizabeth R. Simeral Professor of Physics at Franklin & Marshall College, the book delves into the origins of quantum field theory and builds on it to include areas of modern research, such as intense field laser physics and gravitational interactions in ultrarelativistic limit, where particles approach the speed of light and are subject to curved spacetime.
“Adkins and I saw the need for this book as, in some sense, an update to the original 1950 book by Bethe and Edwin Salpeter,” says Jentschura. “We wanted to create a modern point of reference for advanced students and those who need to refresh or deepen their knowledge of a number of much-needed theoretical foundations for working in atomic physics.”
The new book attempts to modernize the field of study by introducing readers to various topics surrounding quantum field theory, including its role in bound states, laser physics, and the gravitational coupling of Dirac particles. It discusses concepts based on detailed derivations that cannot be found elsewhere in the physics literature. The book is intended for upper-level university students.
“The book also serves to deal with a number of very complicated and advanced concepts that arise naturally when dealing with processes involving elementary particles,” says Jentschura. “These concern the coupling of electrons and positrons to gravitational fields and strong laser fields, as well as the main focus of the book – the coupling of electrically charged elementary particles to form bound states.”
The authors also cover new research techniques, touch on neighboring areas such as the atomic physics of many-particle systems, and aspects of higher-energy physics such as the concept of the renormalization group, which attempts to describe the evolution of the coupling strength of the fundamental interactions with the energy scale used for their observation. It also tries to understand the unification of forces in the natural world – which describes all the forces of nature as manifestations of a single all-encompassing force.
“The book also contains new research results, such as the Foldy-Wouthuysen transformation of order 8,” says Jentschura. “This research could pave the way for better calculations of the energy levels of atomic systems in the future.”