[QUOTE=kladner;377827]I recommend reading "Anathem" by Neal Stephenson. I prefer not to play the spoiler beyond saying that the question of universe/cosmos versus multiverse/polycosmi is pivotal.[/QUOTE]He is in my top tier of favorite writers.

It certainly is pvotal. That's why the Universe might be described
as containing sub-universes, perhaps the galaxies, perhaps the
super clusters. But the topic of Cosmology must be the Universe,
i.e. all.

[QUOTE=davar55;377881]It certainly is pvotal. That's why the Universe might be described
as containing sub-universes, perhaps the galaxies, perhaps the
super clusters. But the topic of Cosmology must be the Universe,
i.e. all.[/QUOTE]Fair enough.

As I've noted before, when you use the term "universe", I translate it into "multiverse" for my purposes as I (and many others) use that term to mean "everything there is, whether we can currently observe it or not". Equivalently, when I use the term "universe", I must try to remember to call it "sub-universe" when conversing with you.

I really fail to see why there is so much misunderstanding of a very little change in vocabulary.

[QUOTE]As I've noted before, when you use the term "universe", I translate it into "multiverse" for my purposes as I (and many others) use that term to mean "everything there is, whether we can currently observe it or not".[/QUOTE]What does "everything there is" mean? Does this include the imaginary? [No, I'm not trying to be obtuse.]

[QUOTE=Zeta-Flux;377891]What does "everything there is" mean? Does this include the imaginary? [No, I'm not trying to be obtuse.][/QUOTE]Not interpreted as being obtuse.

You will have to wait for davar55's definition. For my part a precise definition is difficult to produce on the spur of the moment. A working definition might be "that which is not forbidden by the laws of physics as we know them, together with that which is observable but not necessarily understood in terms of known physics".

As our understanding of the laws of physics changes, clearly so might our conception of "everything there is". Equally, new phenomena may be observed which may not be understood in terms of the laws of physics as understood at the time of observation.

I doubt (please correct me if I'm wrong!) that davar55 claims to have observed, personally or by proxy, everything which is observable or that he claims that the ultimate laws of physics are currently known (with the same provisos).

[QUOTE=Zeta-Flux;377891]What does "everything there is" mean? Does this include the imaginary? [No, I'm not trying to be obtuse.][/QUOTE]

The imaginary is unreal. There is no end to what is unreal,
and it must not be considered part of "everything there is."
"Everything" means reality itself, not the fictional. That's
not to say books ("works of fiction") or fantastic dreams
("flights of fancy") aren't real, but if their content refers to
imaginary things or concepts, those things or concepts
should be excluded from "everything that is."

In particular, since the Universe contains all and only that
which is real, there can be no content in a so-called multiverse
outside of what is in the Universe. You may translate your
multiverse term into "Universe", but not the other way around.
That's the only way to equate them, and since Universe is
the long-term proper term, multiverse would be a redundancy.

The Universe contains all that is. Not just the so-called
observable universe but, if there's more, all of that too.

[QUOTE=Zeta-Flux;377891]What does "everything there is" mean? Does this include the imaginary? [No, I'm not trying to be obtuse.][/QUOTE]

The Universe is real. It may be complex, but its imaginary components
all vanish.

:smile:

[QUOTE=davar55;378718]The Universe is real. It may be complex, but its imaginary components all vanish.[/QUOTE]

When [URL="http://www.mandelbulber.com/gallery_page1.php"]stuff like this[/URL] pops out of deterministic mathematics, imagine what might happen when uncertainty is introduce to the "equation".

I share your enthusiasm for the beauty of fractal mathematical poetry.
And I use "non-determinacy" for uncertainty. The perfection of math
makes it the most "artsy" of the "sciences."

[QUOTE=davar55;378725]IThe perfection of math makes it the most "artsy" of the "sciences."[/QUOTE]

Ah, no...

That would be Economics (or any of the social sciences).

[QUOTE=chalsall;378727]Ah, no...

That would be Economics (or any of the social sciences).[/QUOTE]

I meant artsy in the sense of artistic / esthetic.