A key focus of my work is the history of periodization: how historians divide time and why these divisions matter.
I developed the concept of the time border to show that shifts between periods are not fixed breaks, but dynamic transitions containing both continuity and change. This framework helps reinterpret major turning points such as 1989 and their contested meanings.
I am also a founding editor of the De Gruyter-Brill series Time and Periodization in History, which expands comparative work on historical temporality.