HACETTEPE JOURNAL OF MATHEMATICS AND STATISTICS, cilt.49, sa.2, ss.695-707, 2020 (SCI-Expanded)
We give the graphical notion of crossed modules of Hopf algebras-will be called Hopf crossed modules for short- in a symmetric monoidal category. We use the web proof assistant Globular to visualize our (colored) string diagrams. As an application, we introduce the homotopy of Hopf crossed module maps via Globular, and give some of its functorial relations.