Philosophy
The Metaphysics of Spacetime and the Ontology of Events
Quick fact
In the block universe view, the past, present, and future are all equally real, and events do not 'happen' but simply exist at different spacetime locations—a perspective supported by Einstein's relativity and famously depicted in the film Interstellar.
Why this is interesting
You're standing in a room, but is the room itself real, or just the arrangement of objects? And when that moment passes, does it still exist somewhere? These questions lie at the heart of the metaphysics of spacetime and events.