alright here i go:
There's the current scaling, where we use
the "Brane transplant" upgrade, which states that they can fuse higher dimensional universes/branes with their own, along with
the "Encapsulated realities" upgrade, which states that they have reduced infinite universes into finite spheres. These support a 5D universe, or Low 1-C. I think that this tier could be bumped up.
GENERAL STRUCTURE OF OUR IDLEVERSE (and possibly all the others):
In the
"The multiverse in a nutshell" upgrade, it tells us the structure of the "metacosmos". It says that our Idleverse is just one of an infinite number that are all surrounded by a strange liquid. It also tells us two qualities of Idleverses: that they each have their own interpretation of what the concept of "reality" is (referring to what's real and what's fiction), and that they're riddled with tunnels to dimensions such as the Cookieverse. The latter implies that Portals (a building in the game) either use or are openings into these tunnels, as they are first said to be
doors to the Cookieverse.
Portals being the tunnels that "riddle a reality" is important as they are also likely referred to in
the "Perforated mille-feuille cosmos" upgrade. The upgrade gives us a model of "the geometry of the most basal stratum of our natural world" where we are told to imagine "layers upon layers upon layers", and to "picture billions of worms chewing through it all". Considering that this upgrade is a synergy upgrade between Idleverses and Portals, it would only make sense that this is referring to, well, Idleverses and Portals. If we consider the tunnels and the worm metaphor to both refer to Portals, then that would mean that the layer wording would be of the structure of an Idleverse. We are already told that Portals somehow have the capacity to support merging higher dimensional branes into our own. (I KNOW THAT THIS PART WOULD JUST BASICALLY BE SPECULATION, BUT LET ME HAVE THIS FOR A MOMENT PLEASE) This would imply that the layers referred to in the "Perforated mille-feuille" upgrade would be each a brane, as it would make sense for Portals to support higher dimensional branes if it travels across them. If this is the case, then that would mean each layer of brane should be higher dimensional than the last.
If using the lowest possible reasonable interpretation of the text, this would mean a 6D structure as it says "layers upon layers upon layers", implying at least 6 higher dimensional branes. I think the highest reasonable dimensions you could get from this would be 1000D, as the name of the upgrade uses the pastry "mille-feuille". I know this is a reference to the French pastry, but in this context, it is referring to a bunch of layers on top of each other. The literal definition of "mille-feuille" from French would be "thousand sheets/papers/leaves" (according to DeepL).
With this information, I think the
"String theory" upgrade could also be used as supporting evidence for 5+ spatial dimensions, as it says String theory reveals insight into how the world is structured, which would fit with the "Perforated mille-feuille" structure.
POSSIBLE R>F STUFF:
Referring back to the
"The multiverse in a nutshell" upgrade and how each Idleverse has its own interpretation of the concept of "reality", our own Idleverse's "reality" is likely to be what is referred to in the
"The real world" upgrade, or at least a part of it (covering that in the next section). The Real World is described as a plane of reality that our Idleverse is a dimension of. This is vague, but it likely means a relation similar to how the Cookieverse is a dimension of our Idleverse, supported by the fact that this is an upgrade to Portals, which obviously wouldn't be able to transport things to a space that qualitatively transcends our Idleverse.
But the
"Break the fifth wall" upgrade is an obvious next step to the previous. It is an Idleverse upgrade, implying that it is in relation to Idleverses, and would imply a genuine transcendence of some kind to our Idleverse and possibly the others. Would this count as R>F in some way?
ASCENSION/HEAVEN:
When you ascend, everything mentioned before is reset, and all cookies are turned into Heavenly Chips. Nothing outside ascensions is EVER shown to affect this transcendent plane of existence.
INSANELY SHAKY SCALING/WANK:
I just wanted to cover one possible idea I had.
Cortex Bakers are described as being able to bring anything they think into reality, with the "Every possible idea" and "Unshackled cortex baker" upgrades supporting this. If they have thought of every possible idea, then that would mean that they have realized every possible world. This
sounds like the exact definition stated here for High 1-A+, but please correct me, because even I think this feels a bit shaky.
I think this would mean that Heaven would be another layer into High 1-A+, but I honestly am not sure.
TD;LR:
Lowball: 1-C (6-D Idleverses, assuming The Real World, Past the Fifth Wall, and Heaven don't ascend them dimensionally or qualitatively)
Midball: High 1-C (assuming String Theory is how the world works), to possibly 1-B (assuming 1000D from Perforated mille-feuille cosmos)
Highball: 1-A+ (assuming qualitative transcendence of The Real World, Past the Fifth Wall, and Heaven)
WANK: High 1-A+ (Cortex Bakers think of every possible world)
Thanks for reading! (also sorry that it's so long) Feel free to absolutely shit on my scaling!
