I’d prefer it, if it only meant this was some evidence for a young Earth. I have to say I am very uncomfortable with the idea that each observer will appear as if they are moving away from other observers
It’s not that bad. The usual analogue is to picture the four dimensions of spacetime as being the surface of a balloon. At t = 0, there’s nothing, neither space nor time. At any time after that, any observer is at a point on the surface of the expanding balloon and sees every other point as moving away, and each is respectively at their own center. There is no real ‘center’ (the volume ‘inside’ the balloon does not exist).
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Let’s say we multiply the effect or appearance of this so that it can be appreciated for 3 observers in a large room so that physical objects are moving away from each observer relative to each position.
That can’t actually be what’s happening
It can on the surface of an expanding balloon.
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Every ‘stationary’ point is receding from every other.
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If everything was moving away from you in your room, it is difficult to suppose this was happening to your friend on the opposite end of the room.
Somehow I am caught on one experience invalidating the experience of the other…
I agree, that analogy doesn’t work. But if you take an expanding balloon, volume = 0 at t = 0, mark as many points as you wish as soon as there is any volume…
What makes it weird is that each observer isn’t on the surface of the balloon, but would be at the center of it.
Not the center of the volume of the balloon. Where is the center of the surface of a ball? Collapsing three dimensions into two is a stretch, pun sort of intended. 
But you can imagine three if you like. Just remember that space itself is expanding, not just objects moving apart.
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Would it be wrong to say space is expanding relative to each observer?
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No, maybe that is the point.
Children of the same Father and sharing in the same family you would certainly expect to have some commonality of experience.
It would make for an interesting find to determine whether the expansion of the universe is relative to the observer or the Earth… that’d be something now wouldn’t it
Then you’re not grasping the triviality of what I just noted … This wasn’t some hard-to-comprehend notion; just an observation that of course when I look out, I am the center of my own perceptual experience. The “universe” such as I can see it whether looking around my neighborhood, or through a telescope at any nearby cosmos - will all be “outward from me” in all directions. That isn’t any fantastic claim, and I probably should have just left it unsaid for as much hay as you two are making out of it. Speaking of which …
Here’s a thought. Did you know that you can just use the pencil icons to bundle additional thoughts together into many fewer posts? Instead of littering so many threads with hundred’s of one-liners and quick quotes of yourselves (not a good look by the way!) … maybe try to cut down on all the postings and put more substance (but not too much) into fewer posts. And even better yet … take a break from the internet every once in a while! It’ll still all be here when you get back!
[taking my own advice … check this out! Adding more to my post yet here…]
Absolutely! Especially if your “friend at the other end of the room” is another galaxy that is bajillions of light years away! That’s why we need special telescopes up in space to be able to take in stuff that dim (and in different wavelengths than the visible ones). And it’s also why, if I understand correctly, we still presumably haven’t discovered the “far end” of the room yet. Stuff just keeps going. So that alone makes it a bit of nonsense for us to imagine we could know where any “center” is.
I would reframe the question as how do we know the universe is expanding from every point and not a single point… a single point that we are at the center of.
While I understand this is “unlikely” as one science stack exchange puts it… as “unlikely” as the speed of light being different between observer and object than it is from object to observer, it is a legitimate question given that we appear to be at the center of the universe.
In terms of the universe, Earth and Mars may as well be the same place. The remarkable thing is that if there were an observer on a planet somewhere in every galaxy we can see with the JWST, every single observer would appear to themselves to be at the center of the universe.
Yet it’s not really remarkable, it’s just geometry that can be illustrated on a far simpler level by putting dots on the surface of a balloon and then slowly inflating it from minimum outwards: every dot is geometrically equally the center of the expansion of the balloon’s surface.
Indeed assuming the Bing Bang actually began from a singularity, every point within the universe actually is the center – not merely appears to be the center, but really is!
Quite to the contrary, as I noted just above, if the universe began as a singularity then it has to be what is happening – it’s the only geometry that works.
The surface of the balloon is all there is, though – the analogy is of the two-dimensional surface.
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Yeah, Jason Lisle. I’ve listened to two presentations by him and in both cases found myself thinking, “Doc, you know better!”
In the discussion under one of those presentations someone proposed an experiment that ought to demonstrate that the speed of light in a vacuum is not variable: The idea was to set up a number of paths for photons from a single source to travel, with all the paths being of the same length but differing in the number of reflection points from the simplest single mirror to multiple mirrors so that the photons would travel on a line, following a triangle or square or pentagon, etc.
It seemed a valid approach though someone said that if you broke down each path into vector components it still wouldn’t work.
But the whole issue fails because the speed of light isn’t just a speed, it’s an attribute of space and matter and energy: if light travels faster in one direction than in another, then the mass-energy equivalence formula will provide a different result for how much energy a given mass would be equivalent to depending on the direction – and if Lisle’s instantaneous speed in one direction is correct then a microgram of matter would be the equivalent of all the energy in the universe, which is just silly.
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Yeah that, and you’d have to have smart photons that knew what direction they were traveling. 
It gets tricky: the expansion of spacetime doesn’t stretch the size of stars, or solar systems, or even galaxies, which is why above I said that Earth and Mars may as well be the same place in terms of the expanding universe; for that matter every location within the Milky Way may as well be the same place, since two observers on opposite ends of the galaxy won’t see the distance between them increasing, though both would agree that the distance between them and a galaxy ten billion light years away is increasing.
Especially given that – assuming he hasn’t modified his silliness – Lisle’s proposition is that light travels at a different speed when moving away from an observer than when moving toward that observer. There’s a simple thought experiment that makes hash of that: all we would have to do is send a manned spacecraft to one of Earth’s Lagrange points and have them aim a laser at Earth while someone on Earth aims a laser at the spacecraft – both laser beams would be traveling both towards and away from an observer at the same time.
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