[SiempreViernes]

If duration is a simple displacement between two points in another direction of space then you are right, the two are equivalent: you have then also accepted that time does not flow and lacks intrinsic direction for it is precisely these properties that separates "time" from "space".

Time flows and is irreversible, this is what makes it special, and it is the denying that the flow and irreversibility are inherent properties of time that constitutes "dispelling the illusion".

In other words, saying that "time is an illusion" is saying "time is just like space".

[ben_w]

> Time flows

In what sense? Normally people use that word in a sentence such as “time flows like water”, but water is made of discrete molecules and has momentum, which doesn’t generally ever sound like the subsequent sentence, whatever that happened to be at the — ah ha — time.

> and is irreversible

The funny thing is, thermodynamics is the only law of physics which say that and last I checked nobody knew (or agreed) why, as thermodynamics is inevitable from the other laws but the other laws don’t imply a direction for time.

Of course, there’s also the difference of it acting like imaginary (sqrt(-1)) space…

[goatlover]

> The funny thing is, thermodynamics is the only law of physics which say that and last I checked nobody knew (or agreed) why, as thermodynamics is inevitable from the other laws but the other laws don’t imply a direction for time.

There's also cosmology, which says there has to be a direction to time because of how the universe turned out as a result of the Big Bang, inflation, and everything that followed.

[SiempreViernes]

Look, I'm just listing the properties ascribed to time that sets it apart from distance, not taking a position as to their correctness or how accurate the similes are. If you are ready to accept the timeless unchanging universe that's fine by me, just acknowledge that is what you argue for.

[ben_w]

Calling it “timeless and unchanging” is as incorrect as calling it “x-axis-less and dζ/dx is always exactly zero for all possible variables ζ“.

I think you need to be precise with language for this sort of thing, and avoid similies everywhere, or you’ll run into the same sort of problems quantum physicists have with “observations collapse the wave function” being misunderstood as “conscious minds collapse the wave function”.

[Certhas]

We need precision here. The intuitive notion of time that you start from has a lot of structure.

The question is where does this structure originate? Is there a fundamental thing "time" that has direction, irreversibility, a moment of now, memory of the past?

It doesn't appear so. Instead it seems that most of these properties emerge for complex systems.

If the universe was a box of gas there would be none of the above. So we conclude that time direction, memory, irreversibility, etc... are features of particular configurations of matter that we experience. A universe with the same laws of physics but without these features is conceivable, so they are not fundamental.