Why is there only one dimension of time?
Because every clock reads one and the same parameter, and that parameter enters the laws of motion with the opposite sign from the three space directions. Time in OPH is the count of repairs meeting a region along one continuing history. A tally, a wave, a light signal and a region's own flow all read that single count, with conversion factors fixed by the seams and the temperature. Space has three directions because each carrier's twelve readings split into bands under repair, and only the slowest band, three directions wide, lasts long enough for separated observers to compare it. Write the action for waves running through the records and the three space directions enter with positive coefficients. The wave is second order in the clock and its spatial operator is positive, so the clock direction takes the opposite sign. The result is the minus, plus, plus, plus signature of special relativity, with one time direction and three of space.
Also in Chapter 17: Why Is There a Speed Limit?, Chapter 15: Why Does Space Have Three Directions?.
This answer comes from OPH, Observer Patch Holography. OPH is a rigorous, consistent and complete description of the unified, self-creating computational Universe we inhabit. Its consistency is machine-checked: the fixed point at its core is constructed explicitly, and a theory with a model contains no contradiction.
To understand OPH and check every step yourself, start with the free book Reverse Engineering Reality. It builds the theory from the ground up, and the OPH Notebook answers your questions while you read.
read the free bookask the notebookor ask sage:read chapter 22: Why Do All the Clocks Agree?watch a universe make its own particles