2688: Bubble Universes

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Bubble Universes
The theory finally unifies cosmic inflation and regular inflation.
Title text: The theory finally unifies cosmic inflation and regular inflation.


A bubble universe is a concept in the inflation theory of cosmology in which our observable universe is just one of many "bubbles" of matter and radiation that formed after the Big Bang.

The comic seems to be recursive, where one Cueball's bubble universe contains another Cueball doing the same thing, blowing bubbles, seeming to contain the whole scene within one of the bubbles in the original scene. This may reference cosmological models like the Big Bounce, in which a new universe emerges from a previous universe. A similar view is in the "turtles all the way down" view of the universe, but here the universe is suspended in bubbles, and those bubbles suspended in a universe suspended in bubbles, "all the way down" (or at least one layer down).

The title text claims this theory "Finally unifies cosmic inflation and regular inflation." Cosmic inflation refers to the expansionary phase of the universe shortly after the Big Bang; this would explain why that happened with the simple proposition that it was a bubble and inflated like regular bubbles do. (Ignoring various issues – like the sheer size of the universe, at least in terms of its own scale.) It also makes a pun on special and general relativity, and how they've been hard to merge for a long, long time; the result of which is known as the grand unified theory.

The scene looks like it could be part of an infinite recursion. The two Cueballs and grounds are similar but not identical, a self-similarity (also known as expanding symmetry or unfolding symmetry) common in fractals.


[Cueball blowing expanding bubbles. In the largest one is a whole new universe with another Cueball blowing similar bubbles. The bubbles are progressively darker: the first ones are regular transparent/white bubbles, and as they grow, they turn gray then dark, to match the black night sky, with stars, galaxies, planets and other astronomical bodies]

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Is this a reference to the money kind of inflation? 16:03, 21 October 2022 (UTC)

no 16:29, 21 October 2022 (UTC)
I do think it a form of irony that when I hear "inflation" I do *NOT* think about bubbles or balloons. 20:08, 21 October 2022 (UTC)

​*pop* JLZ0kTC5 (talk) 16:13, 21 October 2022 (UTC)

I think this comic might be referencing the eternal inflation model: as the universe eternally inflates at an exponential rate, bubbles form where the inflation slows down, creating a disjoint multiverse from these bubbles being unable to interact with each other. In this comic, the process is shown as recursive. LegionMammal978 (talk) 16:42, 21 October 2022 (UTC)

I'm included to agree. Should the article be changed? 20:08, 21 October 2022 (UTC)

This comic would be perfect motive for a mug. Fabian42 (talk) 19:04, 21 October 2022 (UTC)

Though I think you mean "motif", although I also agree in principle with your word as well, if it does motivate someone to create one... ;) 20:33, 21 October 2022 (UTC)
I also think it's a really good motivation to create a GIF, I came here to find one... If I can find the time I'll do it! Raphaël xyz (talk) 13:05, 24 October 2022 (UTC)

I don't think this comic references the big bounce, but rather the theory of nested universes. The way it works is each black hole spawns a new universe, and is connected to a white hold in the new universe. If true, our universe came from another universe capable of producing black holes, and since our universe has black holes in it, according to the theory it has in turn created additional universes, each with the potential capability to produce its own black holes and therefore create additional universes. It's kind of like universe propagation.

[Responding to the title text:] As a cosmologist, it most certainly does not! Cosmic inflation took less than 10^-32 seconds involving superluminal expansion of points starting the width of a quark from each other. Any physical gas inflating of a membrane is simply not comparable, and if this is a joke about [1] then it's not funny. I would die on this hill if I had time to argue with you all about this. 21:52, 21 October 2022 (UTC)

Not sure "The Big Bounce" has currency here, as per the current explanation. That's a cyclic theory (generally relying upon a Big Crunch ending one version of universe, the result sparking the next Big Bang... certainly in the version I would favour, if it turned out we were actually not destined towards untempered expansion and either Heat Death or Big Rip as the unending finale) not a recursively embedding one (e.g. Inception-like realities within realities). But that's just my opinion. Someone who actually finds a Big Bounce model of spacetime more satisfying than any open-ended one, even. 22:04, 21 October 2022 (UTC)

There are a number of cyclic cosmologies possibly involving a "big crunch" such as ekpyrotic theories, but we need telescopes much more powerful than the JWST to say anything about whether they are possible, likely, or propose improvements to them. If the pre-inflationary universe was actually a point, we may never know. There is a large variety of other open questions which are much easier to answer. 00:21, 22 October 2022 (UTC)
Any Big Bounce/Crunch worth describing as such needs a crunch-point (or nearly so). Bubbles from bubbles from bubbles has no crunching and is more Steady State With Continuous Generation (i.e. infill to the expansion out of the visible horizon, as a sop to the evident redshift without subscribing to how that finite age requires a BB origin) if you want to introduce any particular real-world™ theories. It has Big Rip similarities, too, perhaps.
Bearing in mind that the comic-universe can be anything it wants, without bearing upon what we do/could see. Plus the real© universe is probably yet so much stranger than even our best guesses (and 'disproved' guesses of old) suggest, and we are are still nowhere near the mark. 08:24, 22 October 2022 (UTC)

This makes me think of his earlier comics. N-eh (talk) 00:15, 22 October 2022 (UTC)

I just realized the two cueballs are not on doppelganger hills. Perhaps an allusion to, as opposed to their being multiple nested universes, one metauniverse in which our bubble universe (with cueball) actually exists blowing regular, non-universe producing bubbles?

I feel a definite reference to M.C. Escher here, his Metamorphosis murals were like this, the end of one part starting another, and I'm sure at least one ended how it started (even if the Cueballs aren't identical, on different slopes of their hills). NiceGuy1 (talk) 06:49, 22 October 2022 (UTC)

If he meant economic inflation, he would have said "...with economic inflation", not "regular inflation". This part of the "explanation" is wrong. 19:59, 22 October 2022 (UTC)

I could be imagining it, but line drawing the hill on the right appears to be quantized...and I've seen arguments about space quantization that prevents such infinite recursions. Philhower (talk) 13:18, 24 October 2022 (UTC)