The evolution of interdisciplinarity in physics research

TL;DR

This paper analyzes 25 years of physics research using PACS codes, revealing increasing interdisciplinarity and a shift towards more integrated, cross-field scientific progress, with condensed matter and general physics as core areas.

Contribution

It provides a large-scale network analysis of physics sub-fields over 25 years, highlighting the rise of interdisciplinary physics and changes in core-periphery structure.

Findings

Increasing interactions between physics sub-fields over time

Core-periphery organization with condensed matter and general physics at the core

Growing share of interdisciplinary physics in the network core

Abstract

Science, being a social enterprise, is subject to fragmentation into groups that focus on specialized areas or topics. Often new advances occur through cross-fertilization of ideas between sub-fields that otherwise have little overlap as they study dissimilar phenomena using different techniques. Thus to explore the nature and dynamics of scientific progress one needs to consider the large-scale organization and interactions between different subject areas. Here, we study the relationships between the sub-fields of Physics using the Physics and Astronomy Classification Scheme (PACS) codes employed for self-categorization of articles published over the past 25 years (1985-2009). We observe a clear trend towards increasing interactions between the different sub-fields. The network of sub-fields also exhibits core-periphery organization, the nucleus being dominated by Condensed Matter and General Physics. However, over time Interdisciplinary Physics is steadily increasing its share in the network core, reflecting a shift in the overall trend of Physics research.