Temporal Dynamics of Fragmentation in Reddit Meme Stock Communities: A Network Analysis of the GameStop Event

This paper examines how episodic events, such as the GameStop short squeeze, disrupt and reorganize the structure of online discourse.Focusing on Reddit's meme stock community, we analyze how content-level thematic coherence changes over time by comparing full-period post similarity networks with daily snapshots.We find that, despite widespread lexical diversity, a dominant semantic cluster emerges when data are aggregated, while daily networks reveal sharp spikes in fragmentation and entropy aligned with key moments in the event.These findings demonstrate how structural patterns in online content can reflect collective narrative dynamics, even in the absence of user interaction data.