Scientific papers in the field of physics are usually very short and cover a very limited topic. A notable exception to this is an article recently published by physicists from the Universities of Münster and Düsseldorf. The article is 127 pages long, cites a total of 1075 sources and covers a wide variety of branches of physics – from biophysics to quantum mechanics.

Time axis showing the number of publications related to the functional theory of dynamic density. Credit: M. te Vrugt et al.
The article is a so-called review article and was written by physicists Michael te Vrugt and Prof. Raphael Wittkowski of the Institute for Theoretical Physics and the Center for Soft Nanoscience at the University of Münster, together with Prof. Hartmut Löwen from the Institute for Theoretical Physics II at the University of Düsseldorf. The purpose of such review articles is to provide an introduction to a particular field and to summarize and evaluate the current state of research in this field for the benefit of other researchers.
“In our case, we are dealing with a theory that is used in many areas – the so-called dynamic density functional theory (DDFT),” explains the latest author Raphael Wittkowski. “As we cover all aspects of the topic, the article turned out to be very long and comprehensive.”
DDFT is a method for describing systems that consist of a large number of interacting particles, such as those found in liquids, for example. Understanding these systems is important in many research areas, such as chemistry, solid state physics or biophysics. This in turn leads to a wide variety of applications for DDFT, for example in materials science and biology.
“DDFT and related methods have been developed and applied by a number of researchers in different contexts,” said lead author Michael te Vrugt. “We explored what approaches there are and how they are interrelated – and for this purpose we had to do a lot of work as historians and detectives,” he adds.
The article was published in the journal Advances in Physics, which has an impact factor of 30.91, making it the foremost journal in the field of condensed matter physics. It only publishes four to six articles per year. The first article on DDFT, written by Robert Evans, was also published in “Advances in Physics,” in 1979. “This makes it particularly gratifying that our review has also been published in this journal,” said secondary author Hartmut Löwen. “It covers all major theoretical aspects and areas of application of DDFT and is likely to become a standard work in our research area.”
Reference: “Classical Functional Theory of Dynamic Density: From Fundamentals to Applications” by Michael te Vrugt, Hartmut Löwen and Raphael Wittkowski, December 20, 2020, Advances in Physics.
DOI: 10.1080 / 00018732.2020.1854965
The Wittkowski Working Group is funded by the German Research Foundation DFG (WI 4170 / 3-1). Löwen’s working group also receives financial support from the DFG (LO 418 / 25-1).