First of all I don't claim to be "right". So please read the rest of this in that light. I just enjoy thinking about these things, and I tend to do so by ignoring most all physics of the 20th century and really going back to first principles and thought experiments much like the greeks and early natural philosophers did. I won't go into all the first principles here, so apologies for anything that seems unsupported.
Lloyd wrote: ↑Wed Aug 24, 2022 2:44 pm
There's no reason empty space can't exist. It has volume, which is 3 dimensions of length. Length exists, doesn't it?
Length is merely a measurement in a coordinate system. A measurement of what? something physical. Length does not exist as something unto itself.
If space is "empty" then what does it consist of? Nothing? How can nothing exist? Considering all of existence -- the "beginning" -- either something exists or nothing exists. We are here, hence something exists and not nothing. I think therefore I am.
If somehow both "something" (matter) can exist and also nothing, then what is the boundary between something and nothing? What stops the something from spilling into the nothing? Wouldn't it then be something? Anyway, you have a boundary condition to resolve. And that's never simple. How can "fields" exist in nothing? Stated differently, explaining how "nothing" can exist at all, is at least as hard as explaining how "something" can fill all of space.
You may choose to believe that somehow nothing can exist. Though you will be disagreeing with Aristotle, Descarte, Maxwell, Lorentz, Tesla and many other big thinkers. (and agreeing with others) At this time, I choose to believe the simpler (occam's razor) explanation is that all of everything is filled with "something". In my present conception, that something is fractally self-similar. In this view, the ether is something like an infinitely dense superfluid/supersolid "ocean", and our "matter" is high energy concentrations or vortexes or vibrations in this ocean. The matter at lower fractal scales (to infinity) are what fill space, and our matter contributes to the ether for scales above/larger than ours.
I believe that what has been missing from physics of the very large and small, and especially from ether discussions, is the fractal, scalable, self-similarity that we see over and over again in nature.
The so-called ether is probably photons and photons are probably infinitely divisible.
I don't believe in the concept of photons as some kind of particle. I believe light to be purely a wave in the medium of the ether. Waves do not exist on their own, but only as transmission of movement (energy) between constituent particles of the medium.
Now one can give a wave another name, but I prefer just to call it a wave.
If ether were tightly packed, with no space between ether particles, how could anything have motion?
yeah, this is hard to wrap ones mind around. I haven't fully done so myself, but I have kind of an idea.
Waves transmit faster in dense materials. But it also depends on elasticity/compressability, which is a kind of motion. And for transverse waves in solids it depends on shear strength. But as a basic rule of thumb, the more dense a material, the faster waves travel through it. eg waves travel fastest in solids, then liquids, then gases. The fact that light travels very quickly as a transverse wave is a strong indicator that it is travelling through a dense, solid-like medium.
As for matter (at our scale) having motion... well, I think of the ether as being like a super super super fluid (or "viscous solid") with smaller and smaller constituents recursively all the way down to infinity that all can slip by eachother because they are mostly operating at different scales. Similarly to how a submarine can move through the ocean, which we perceive as "full" of water, so our "matter" (which is concentrations of dynamic ether) can move through the ether... remembering also that matter itself is 99.99999.... "empty" (or ether-filled).
And how could one ether particle be distinguished from another if there's no space between particles? At all orders of magnitude there is likely matter and space, ether/photons being microcosmic matter.
At any given scale, space/ether is not full of "matter" belonging to that scale. Just as at our scale there is immense distance between solar systems, planets, and galaxies. But the ether is not just particles from 1 scale below us but is the sum of an infinite number of scales below us, forever. So for a given nanometer of "space" there is an infinity of subdivisions, each containing a tiny percentage of "matter" at that level, until every last bit is filled.
I guess a way to envision this is if you mentally take our visible universe n^1 and shrink it down to the size of an electron or so, and say ok, that's an electron-sized unit of ether n^-1. And then you mentally enter that unit of ether, shrink the entire thing down to the size of an electron at that scale, and call that a unit of ether at n^-2. Turtles all the way down.
As to how this all works out exactly, I don't claim to know. For now, it's just fun to think about. However, I have started making some notes for ideas how to model this with some data structures and a recursive computer algorithm. Perhaps I can have a better answer in the future.
Also, the universe and the space within it is not expanding significantly, since the redshift is due to ionization (the Compton effect), not acceleration (the Doppler effect).
I agree space is not expanding though I attribute redshift to "tired light" which I conceive as simply light waves losing energy and elongating, which all waves travelling through a medium do. here again, light is no more special than a water wave.
ps: here is a nice writeup of the history of ether thinking, and some problems the theory ran into towards the "end". I didn't know all this, so I actually repeated a fair amount of it in my own mind, such as concluding the ether must be dense and have solid-like properties.
https://science.slashdot.org/comments.p ... d=62814531