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You might want to read some of Julian Barbour's writing, in particular his "The End of Time: The Next Revolution in Physics" where he tries to explain a theory of timelessness with an apparent arrow of time.

Here is a rather long interview I found (and only skimmed to confirm its mostly relevant): https://www.edge.org/conversation/the-end-of-time

> In my view, the universe only ever exists in one state

> All of the universal constants come down to comparing a present state to a previous-present state

The problem with this as you state it is that it is not relativistically invariant; there is no absolute "present" for the universe as a whole.

However, a more restricted version of this, where the notion of "present" is not applied to the whole universe but only to a single observer's worldline, works fine.

there is no absolute "present" for the universe as a whole.

And if God played chess, what would be his next move? We entertain the absolute/omniscient perspective to discover answers in our simplest of games, where truth appears relative because our access to information is finite.

I'm always a fan of applying that strategy to the bigger games. Physicists might benefit if they did the same, but I understand we are at the point where philosophical assumptions form the basis for many axioms.

> And if God played chess, what would be his next move?

Along any particular person's worldline, God's "next move" is whatever the next thing is that that person experiences.

For the universe as a whole, there is no well-defined "next move", for the same reason there is no well-defined "present".

The thing that is tricky though is that the changes in state are affected by the the state's own state regarding the state of the state change.

Put another way:

My writing this comment is changing the state of our universe. I'm writing it because I perceive the state change. If time is solely illusion then there would be no difference in the state between Tick #145 and Tick #146, but there is and it is this comment, which means that the universe (or at least our universe) is dependant on something that you all say doesn't exist.

I'm not saying you're all wrong, but it is a pretty surprising thing if it's true and modal realism is false.

State-change received and confirmed. Thank you for updating the universe.

I am the state.

Illusion is in reference to the phenomenology of mind, I guess, which in epistemological terms must precede a minding physics.

See the universe as a type of cube. (It's a 4d hypercube, but don't worry about the 4th dimension just yet.) The cube is vastly bigger at one end, like a horn.

An explosion occurred at the narrow end of the box/horn. We, the Earth, the Sun, solar system, Milky Way, everything we can see are the particles flying away from the explosion. The path we're tracing are the world lines. Indeed, these can be seen as tunnels, and we are a charged force propagating through them.

We perceive time as a cross section of the cube/horn. But things slow down where they gather. And so the actual cross section would be very lumpy. But not to our limited perception.

>I always saw time as a way of applying numerical labels to a state of the universe. In my view, the universe only ever exists in one state, albeit constantly changing at the "speed" of light.

If that was the case there would be nothing to take it from state N to state N+1 because (as per your definition) there's nothing in-between states.

indeed, in such a concept there is no room for causation between the smallest time steps. That's in line with basic human thinking, it is how it is. I mean, I settled on time being the measure of change, every change is a tick. However, there doesn't need to be a smallest time step if you use rational numbers or sum such. But the

You might like this: https://en.wikipedia.org/wiki/Cellular_automaton

I think about time in a similar manner. The delta between point A and point B is the mutation state and point A is the initial state that was mutated into B.