When real-world events take center stage, online discussions don’t just grow-they become more repetitive yet structurally different. We found that conversations during major events are easier to compress, revealing a high degree of semantic redundancy. In other words, people echo similar messages, reinforcing key themes and reactions. Interestingly, while discussions become more redundant, they also shift in structure-users combine words in new ways compared to everyday conversations. This suggests that real-world events don’t just amplify online discourse; they reshape the very way people communicate.

Users Navigating the Time-Semantic Space The shifts in online conversations during real-world events aren’t just collective phenomena—they also emerge at the individual level. To capture this, we mapped user interactions as trajectories in a time-semantic space, analyzing how individuals "walk" through this evolving landscape. This approach reveals how user behavior adapts dynamically, balancing between personal expression and the collective flow of conversation during major events. As users become more active, their semantic space shrinks, meaning their language becomes more focused and repetitive. Interestingly, those with broader vocabularies tend to engage more frequently, shaping the overall direction of discussions.