Does "simply move apart" imply motion in the common sense? Can something move without motion? — jgill

The problem though, as I've read, is that this "moving apart" can be much faster than the speed of light. And since the motion of objects is limited by the speed of light in relativity theory, this "moving apart" cannot be categorized as motion, in order to avoid contradiction. So in the following example, a galaxy can be observed to be "...receding from us well in excess of the speed of light...", bit in reality, that galaxy is "...hardly moving at all!', "...moving through space at ~2% the speed of light or less...".

If we were to ask, from our perspective, what this means for the speed of this distant galaxy that we're only now observing, we'd conclude that this galaxy is receding from us well in excess of the speed of light. But in reality, not only is that galaxy not moving through the Universe at a relativistically impossible speed, but it's hardly moving at all! Instead of speeds exceeding 299,792 km/s (the speed of light in a vacuum), these galaxies are only moving through space at ~2% the speed of light or less.

But space itself is expanding, and that accounts for the overwhelming majority of the redshift we see. And space doesn't expand at a speed; it expands at a speed-per-unit-distance: a very different kind of rate. When you see numbers like 67 km/s/Mpc or 73 km/s/Mpc (the two most common values that cosmologists measure), these are speeds (km/s) per unit distance (Mpc, or about 3.3 million light-years).

The restriction that "nothing can move faster than light" only applies to the motion of objects through space. The rate at which space itself expands — this speed-per-unit-distance — has no physical bounds on its upper limit. — https://www.forbes.com/sites/startswithabang/2020/06/12/ask-ethan-how-does-the-fabric-of-spacetime-expand-faster-than-the-speed-of-light/?sh=1753c4723b5f

The very real problem, is your irrational worldview of the past, current and future efficacy of all scientific endeavours. — universeness

This is not at all true, I have very real respect for sicentific endeavours, and I am truly amazed, even awed by the great achievements derived from scientific knowledge. The fact that I practise philosophical skepticism has little if any bearing, on the great respect that I have for the scientific method.

You, on the other hand, profess a false premise that philosophical skepticism is derived from an "irrational worldview".

Again we see your lies. We all know we can assign point A and B and we can traverse the distance between them. You accept that demonstration but you will not accept that demonstration as proof that your statement of: — universeness

I did not accept your demonstration, I proved it to be equivocation. Your seat and your toilet can not be said to be "points", in any rigorous logic. Since we are concerned with the rigorous logic of mathematics, your use of "point" here is equivocal.

You can define "point A" and "point B" in any way that you please. But if you stray from the mathematical definition of "point", then you argue by equivocation, because problems of mathematics is what we are discussing here. Therefore your argument is bogus, and irrelevant, as being nothing but an equivocation fallacy. — Metaphysician Undercover

A point is a 0-dimensional mathematical object which can be specified in n-dimensional space using an n-tuple (x_1, x_2, ..., x_n) consisting of n coordinates. In dimensions greater than or equal to two, points are sometimes considered synonymous with vectors and so points in n-dimensional space are sometimes called n-vectors. Although the notion of a point is intuitively rather clear, the mathematical machinery used to deal with points and point-like objects can be surprisingly slippery. This difficulty was encountered by none other than Euclid himself who, in his Elements, gave the vague definition of a point as "that which has no part."

The basic geometric structures of higher dimensional geometry--the line, plane, space, and hyperspace--are all built up of infinite numbers of points arranged in particular ways.

These facts lead to the mathematical pun, "without geometry, life is pointless."

The decimal point in a decimal expansion is voiced as "point" in the United States, e.g., 3.1415 is voiced "three point one four one five," whereas a comma is used for this purpose in continental Europe. — https://mathworld.wolfram.com/Point.html

Your "demonstration" was very obviously an argument through equivocation, and therefore invalid. So I am still waiting for a proper rebuttal, something more substantial than a hurling of insults.

Your "demonstration" was very obviously an argument through equivocation, and therefore invalid. So I am still waiting for a proper rebuttal, something more substantial than a hurling of insults. — Metaphysician Undercover

This is like trying to reason with a Kent Hovind or Ken Ham style sophist.
You are not worth any more of my time. You offer nothing more than a Pantomime style exchange:
MU: Oh no I don't! and oh no 'it' isn't!
Rational Thinkers: Oh yes you do! and oh yes 'it' is.
Ad Nauseam! bye bye!

The problem though, as I've read, is that this "moving apart" can be much faster than the speed of light. And since the motion of objects is limited by the speed of light in relativity theory, this "moving apart" cannot be categorized as motion, in order to avoid contradiction — Metaphysician Undercover

Yes. I stand corrected. The limits due to the speed of light seemed contradictory. It's difficult to imagine "nothing" expanding. It's an age of discovery and conjecture where our intuitions - formed by everyday experiences - must give way to a deeper reality in which math replaces direct sensations. And perhaps a newer, emerging math replaces that which has served so well up to this point.

Points and continuums, space and time . . . . . remain beyond complete understanding, although we manipulate them confidently. When I asked an old friend, an analytic number theorist, what he thinks of real analysis, he says, "It's very, very complicated and it starts with a metaphysical notion, points."

Yes. I stand corrected. The limits due to the speed of light seemed contradictory. It's difficult to imagine "nothing" expanding. It's an age of discovery and conjecture where our intuitions - formed by everyday experiences - must give way to a deeper reality in which math replaces direct sensations. And perhaps a newer, emerging math replaces that which has served so well up to this point. — jgill

Remember that the proposal that the edge of the universe may be expanding at a superluminal speed, is a 'relative' measure. The result comes out of consideration of speed 'relative to our position.' It is not an actual speed. If you were at the edge of the universe, you would not be travelling at a superluminal speed.

And perhaps a newer, emerging math replaces that which has served so well up to this point. — jgill

That's what I'm talking about, a mind open to the possibility of solving the problems rather than denying that the problems exist.

Remember that the proposal that the edge of the universe may be expanding at a superluminal speed, is a 'relative' measure. The result comes out of consideration of speed 'relative to our position.' It is not an actual speed. If you were at the edge of the universe, you would not be travelling at a superluminal speed. — universeness

This image you propose, of an expanding "edge" of the universe presents a misunderstanding of "expansion". It makes no sense to say "If you were at the edge of the universe". And your mention of "speed' relative to our position'...not an actual speed" is utter nonsense, because all speed is "relative", and this leaves your "actual speed" as totally meaningless. That's the point of relativity theory.

The more we learn about it, the more complicated the expansion of the universe seems to be. In the region near our galaxy, the expansion seems less rapid than for the universe as a whole. In fact, it appears that the combined gravitational pull of a very large cluster of galaxies in the constellation Virgo is actually retarding the local rate of expansion to half the rate for the universe as a whole. We're finding evidence of how gravity attracts even over distances of hundreds of millions of light years. Although there must be many very distant galaxies and quasars that we are not yet able to detect, astronomers have observed radiation from an even more remote source, literally at the edge of the observable universe. — https://history.nasa.gov/EP-177/ch4-9.html

There is a limit to how far we can "see", or observe, within the universe, determined by the speed of light, and the amount of time that the universe is known to have existed for. This is known as the cosmological horizon, "the edge of the observable universe". It could be called a temporal edge:

https://www.forbes.com/sites/startswithabang/2020/07/22/what-is-it-like-as-you-approach-the-edge-of-the-universe/?sh=43e638da7152

Or, it might be said to be not an edge at all, just the illusion of an edge:

https://www.skyatnightmagazine.com/space-science/does-universe-have-edge

because all speed is "relative", — Metaphysician Undercover

Yeah, sure, woo woo boy, the speed of light is relative :roll: How about 'proper speed,' is that also relative in your wee esoteric world? I respond to you just for the benefit of others who might be mislead by YOUR

utter nonsense — Metaphysician Undercover

According to Wikipedia, "proper speed" is the speed from the observer's frame of reference, which in your example, would be equivalent to "relative to our position". So if "actual speed" is meant to be "proper speed", there is no difference between the speed relative to our position, and the actual speed. That is what leaves your statement as utter nonsense:

The result comes out of consideration of speed 'relative to our position.' It is not an actual speed. — universeness

See how you completely dodged my 'the speed of light is not relative,' response to your 'all speeds are relative BS.' You did a quick Wiki search about 'proper speed' and then demonstrated your lack of understanding of the use of the concept. :lol:

The speed of light is relative. It is the same relative to any frame of reference. That's the principle which allowed Einstein to include the motion of light into relativity theory, in his special theory of relativity.
Can't you ever say anything intelligent?

Points and continuums, space and time . . . . . remain beyond complete understanding, although we manipulate them confidently. When I asked an old friend, an analytic number theorist, what he thinks of real analysis, he says, "It's very, very complicated and it starts with a metaphysical notion, points." — jgill

The issue I see with the "expansion of space", is that in order to conceive of numerous distinct locations from which everything is receding, it is necessary to assume that these locations are "points" in space which have real substantial existence. These points are not particles of mass or any form of elementary substance, but points of space itself. So this requires a type of understanding of space which allows for real points (as opposed to arbitrarily assigned points of location), and a determination of the characteristics of these points which would allow them to be identified.

The speed of light is relative. — Metaphysician Undercover

The speed of light is a universal constant you complete idiot!

Sure, the speed of light is constant, but as is the case with all motion, the speed is always relative to a frame of reference. That's why your statement ("The result comes out of consideration of speed 'relative to our position.' It is not an actual speed") is nonsense. All speed is relative, and to distinguish "actual speed" is nonsense.
I suppose you are going to argue that the speed of light is relative to nothing, and this makes it an actual speed rather than a relative speed?

I suppose you are going to argue that the speed of light is relative to nothing, and this makes it an actual speed rather than a relative speed? — Metaphysician Undercover

No, as you are too far gone!

White hole (instead of "Big Bang"):