Scaling laws of political regime dynamics: Stability of democracies and autocracies in the 20th-century

In light of the current rise of authoritarian regimes and the anti-liberal
tendencies in some established democracies, understanding the dynamic and
statistical properties of political regimes is of critical importance.
Despite their relevance, a comprehensive quantitative assessment of these
dynamics on a historical scale remains largely unexplored, and the notion
that democratization is an irreversible process has gone mostly
unchallenged. This study provides a rigorous and quantitative analysis of
political regimes worldwide by examining changes in freedoms of
expression, association, and electoral quality throughout the 20th
century. Utilizing the multidimensional V-Dem dataset, which covers over
170 countries across more than a century, alongside tools from statistical
physics, we demonstrate that historical political regime dynamics follow
scaling laws, which are a hallmark of diffusion. We identify three
distinct types of scaling laws in the data: super-diffusive behavior in
destabilizing autocracies, random-walk dynamics in hybrid regimes, and
sub-diffusive behavior in democracies and stable autocracies. Using these
results, we also offer a novel perspective on the propensity of civil
conflict.