The study of physical laws as they operate across the four dimensions of spacetime, treating time not as a separate parameter but as a full coordinate alongside space. In 4D physics, objects are understood as four-dimensional worldlines—complete trajectories through spacetime from beginning to end. A person isn't a 3D object that moves through time; they're a 4D object—a spacetime worm—with their entire existence laid out like a path. 4D physics explains why time seems to flow (we're just moving along our worldline), why the past feels fixed (it's just the part of the worm behind us), and why you should have paid attention in relativity class (because your GPS needs 4D corrections to work). It's the physics of block universes, where past, present, and future all coexist, and your sense of "now" is just a local illusion.
*Example: "He tried to explain 4D physics to his girlfriend after being late again. 'According to block universe theory, my being late is just a point on my four-dimensional worldline. It's not a choice; it's geometry.' She said his worldline was about to intersect with the couch if he didn't start being on time. 4D physics had failed to save him."*
by AbzuInExile February 16, 2026
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