>[!abstract] >In theoretical physics, the problem of time is a conceptual conflict between quantum mechanics and general relativity. Quantum mechanics regards the flow of time as universal and absolute, whereas general relativity regards the flow of time as malleable and relative. This problem raises the question of what time really is in a physical sense and whether it is truly a real, distinct phenomenon. It also involves the related question of why time seems to flow in a single direction, despite the fact that no known physical laws at the microscopic level seem to require a single direction (Wikipedia, 2025). >[!related] >- **North** (upstream): [[Metaphysics]] >- **West** (similar): [[Wheeler–DeWitt equation]] >- **East** (different): [[Emergent time]], [[Relational time]] >- **South** (downstream): [[Timeless universe problem]] (the issue that, in quantum gravity, time disappears from fundamental equations, raising questions about dynamics and change)