Maybe one can think of it this way? Think of a wave in a expanding space, assume it to 'elongate', that also means that for a observer observing light 'propagating' in some defined portion of a inflating space, he will find the light to redshift, to then ultimately 'disappear' from observation. It won't mean that he will measure different speeds though.

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what it might ask about though is the relation of energy, as represented by that light increasingly red shifted due to a expansion, and a 'space'? And there it depends on how you define it, as a 'field'? How then will conservation laws describe it? I prefer one where communication builds a universe myself, and defines what exist, in such a universe 'space' is a weird idea and a secondary to energy, or 'light'. Because that is what communicates as it seems to me. That one in its turn can then be related to if you define light as 'propagating' or not? Assume it to be a 'flickering' field for example, 'flickering' in the way all 'observers', animate or inanimate, observe communication between them, as well as inside, because that is also 'light communicating'. Doing so the duality is real, dependent on type of 'experiment/observation'.

also, doing so we can find the limits in 'c', that both represent a speed, added together from a local definition of lights 'propagation' of a length, as timed by a clock. And there we then if we prefer, which I do, can define two local constants, or three. We can define 'time' as a local constant equivalent to 'c', we can define a length as a local constant equivalent to 'c', we can define any choice of clock as equivalent to 'time' too, when split into even chunks. That makes the clock equivalent to time, to 'c'. Actually, what it really do is to simplify time, time is 'c' through such a definition. And that is what clocks measure.

So there you have a constant 'flickering'. and in two different ways

The most important to me is if you think of Planck scale as the one defining a 'microscopic limit'? If you do the 'flickering of time' starts there, over the whole field. And that one is unnoticeable for us. The second description is the one in where 'observers' experiment, or if you like 'observe' those signals. That one is a result of the 'flickering field' existing if so

as without it nothing would happen. That then would make 'time' what makes things happen, which pleases me

What this describes is a 'field' as a clock, the clock keeps a constant 'flickering' defining a 'time', as a metronome of sorts. The other side of this field is 'mass' and 'motion', creating observer dependencies, as it 'measures/observes/experiment' (pick thy choice). But it gives the metronome (field) a even steady rhythm, as locally measured, and when comparing that local rhythm over a 'space' to some other 'rhythm' , give us observer dependencies. But it doesn't explain what 'space' is. What it assumes though is that observer dependencies is something related to how we treat that space separating you from what you observe, as well as how that space treats you, as your constituents communicating with each other. Meaning that a moving lightclock is indeed a different thing from a comoving, being at rest with you. Space exist, so do motion, and mass.

As a very outlandish idea, think of the field as a plane. Think of everything 'mass' as those able to measurably communicating in between themselves, and as nodes, existing in this plane. Dimensionally, and observer dependently, I guess that those nodes also could be defined as adding further dimensions by us 'observers', having the ability to communicate in between. As I said, outlandish idea.

Also one need to see how I define a observer there. Animate (life) or inanimate (rock) doesn't matter. What I'm after is the ability to communicate, receive and leave 'information'.