Is time an illusion?
Time is real, and the one piece that is missing is a single present moment shared by everyone. No instrument reads such a moment and no procedure produces one. The rest is physical. Events are ordered wherever one depended on another, repair gives that order its one-way direction, and each observer's state sets a rate. People say time is subjective loosely, and here the phrase names an exact object. The rate comes from a flow computed from one specific state, so two observers holding different states run different flows, and no third flow stands above them for either to miss. A region with nothing left to settle drives no clock at all. A clock appears once an observer has read something. A shared time is something observers build, the way ships agree on Greenwich.
Also in Chapter 7: Why Is There No Such Thing As Now?, Chapter 16: Why Does Time Run, and Only One Way?.
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 21: Why Does Time Feel Like It's Moving?watch a universe make its own particles