If we think of time as change turning future to past, rather than the narrative effect, of the present moving past to future, than time is an effect, like temperature, pressure, color. Think frequencies and amplitudes.
As you observe, without activity, there is no clock, nor would there be temperature, etc.
So there is no “dimension” of time, as the past is consumed by the present, in order to inform it. Aka, causality and conservation of energy.
Feedback loops all the way down.
Keep in mind the Big Bang Theory cannot be falsified, as whenever there is a discrepancy between prediction and observation, some enormous, otherwise invisible force of nature is applied and all is well.
Before Inflation, Dark Matter and Dark Energy, the original patch was when they realized redshift increases proportionally in all directions. Meaning that we appear to be at the center of this expansion. So it was changed from an expansion in space, to an expansion of space, because “spacetime!” Ignoring the central premise of General Relativity, that the speed of light remains Constant. If it is being redshifted, then the speed of intergalactic light is not Constant to intergalactic space.
Two metrics are being derived from the same light. One based on its speed and one based on its spectrum. Since the expansion is relative to the speed, ie, presumably more lightyears as it expands, that makes speed the denominator and thus the actual metric. If the spectrum was being considered the denominator, then it would be a “tired light” theory.
So an optical explanation for redshift would be reasonable to consider, since we are at the center of our point of view.
As multi-spectrum light “packets” do redshift over distance, as the higher spectrum wavelengths dissipate faster, that implies we are sampling a wave front, not observing individual photons, traveling billions of lightyears.
That would suggest more of a “loading theory” of light/photons.
If redshift is optical, than the cosmic background radiation would be the light of ever further sources, shifted off the visible spectrum, so it will be interesting to see what information the James Webb gives us to work with.
Considering the tendency to patch the old, I would not be surprised if we are told that the edge of the universe is a mirror, thus only appearing infinite.
Epicycles were brilliant math, but lousy physics, not because all the details hadn’t been worked, out, but because the big picture hadn’t come into focus.
