This classification defines universes based on how similar they are to our own or how different they are. This is obviously a subjective classification. Someone from another completely different and alien universe to ours would classify ours in a very different way. Despite this page being ultimately about universes or universe level structures, it could potentially be applied to any verse of any level, to any cosmological or similar structure.
These are universes that appear to be very much identical to our own. They don't have be "alternate versions" of our own though. They don't need to have the same galaxies and planets on the same places. Their contents can be as different as possible under the limitations that they at least appear to function by the same rules. They have similar numbers of dimensions with similar properties, space and time exist and work in similar ways. They contain matter and energy with similar if not identical properties and our matter could perfectly enter and exist in there without causing any problems. In short they would be recognized as having a very similar type of existence.
- Most types of Universes would probably fall in this category unless defined otherwise
- The fundamental example that defines this category is our universe.
This category is for universes that can still be identified by us as such, being similar to our own in most ways. It is for universes that have some different detail(s) that would still allow us to identify them as something familiar but somewhat weird in one aspect or another. Some curious detail that will give away the fact that its not our universe and that can even cause us to wonder how would that be possible under the laws of physics as we know them, and maybe its actually not possible at all, but that still intuitively seems to follow such laws, at least in appearance. The essential aspect is that the difference must be something that our brain can accept as not being jarring or crazy. Something that would cause us to go like "that's weird" when observed, like a curiosity.
- A universe with atmosphere every where in space. It can slowly become less and less dense but never getting to the point of having the void of space actually existing, except maybe on very far away areas very far from any super-cluster or anything else. This would make it possible to actually fly to the moon and flying creatures like birds could be able to move between planets.
- A universe with the emptiness of space filled with some type of liquid. Space travel would be more akin to underwater travel. Planets can still have atmospheres that exert enough pressure to keep the liquid at bay and stars could cause it to vaporize around them. There is the possibility of the existence of aquatic life of many types in such liquid.
- A universe with the emptiness of space not empty at all, but instead being filled with matter, probably rocks. Space travel would be more akin to digging, digging and digging and digging through all the astronomical distances between the pockets of empty space that would contain solar systems similar to our own floating in there. All the gravity of matter could balance itself out on such empty spaces somehow. Smaller pockets of open space could exist inside the mater filled space, like huge caves that could also support life in many ways. Very high density cores of molten rock and metal could exist in specific points of high pressure where the gravity is the highest. These universes could be an amazing source of almost endless resources for multiversal civilizations. Larger and larger caves could have enough space for normal astronomical structures to exist inside them like solar systems, galaxies, clusters, etc. A cave large enough could even contain the entire observable universe as we know it. In that case, the gravity of the surrounding material could explain the constant pull that causes the constant expansion of the universe. Differences on the density of that material could even help explain things like the Dark Flow.
- Instead of being black, the void of space has some other color. That other color would be what we see as the absence of color instead of black. Even stranger would be for space to be filled with all kinds of colors, with the color varying from area to area. Possibly one color in one solar system and another color in other and, sometimes, multiple colors mixing together. These colors can change or be static, they can be based on locations in space, meaning that things would move to areas of other colors or they can move around with the astronomical objects leaving the color around solar systems to be always the same. The colors could be affected by the color of the light of close stars or other illumination forms or be independent and unaffected by it.
- A universe where the answer to life, the universe and everything is not 42 but is, instead another integer number, somewhat close to that. If the answer is very different, being a much larger number or maybe a negative number for example, this will probably be a Surreal-verse. If it is not even an integer but some other type of number, like real, imaginary, infinite, etc it will probably be even further away than that, possibly becoming a Un-verse. It could probably be assumed that the answer to that question in our actual universe would not actually be some random number but something else much deeper, if it even exists in a concise way. In that way, having a number like 42 as an answer already could classify such universe as a Weird-verse in the first place. Different more plausible answers could exist for different Normal-verses. There is a possibility that the answer, when a number, actually represents the coordinate(s) of said universe inside the multiverse containing it. If that is the case, the result could be a set of numbers instead of just one, one coordinate for each dimension in the multiverse. It could also represent any other property.
A universe that is much stranger than the previous category. It's no longer just weird, not just curiously different in some way. It is jarringly so. What makes it different is something so strange that it can only be classified as surreal.
- A universe with its space filled with matter, only instead of rock it is filled with Swiss cheese. The holes in the cheese are the places where normal solar systems form and exist. Possibly different areas of the universe, maybe galaxy sized or cluster sized areas can have different types of cheeses. Just imagine the smell.
- A universe where the space is constantly on fire. The vacuum point energy that exists in all vacuum always bursts into flame where there are no matter to compensate for it. The presence of matter reduces this effect, the more matter the lesser it is. The more perfect the void the higher the effect and the higher the temperature it reaches. A perfect void could even be theorized to achieve infinite temperature. This energy is never consumed by the creation of the flames, it never runs out and the flames never go out unless matter is positioned in that space. This can also be a consequence of the absence of gravity. The presence of gravity lowers the temperature and the flames, eventually putting them out completely. Gravity and matter only have this effect on the void flames though, not on normal fires. This universe can appear to follow conservation of energy and normal entropy decay in all other cases. The void flames are either an exception or property of the fabric of space time itself or maybe the manifestation of the null point energy or quantum fluctuations that exist in all vacuum.
- A universe where stars are mirror like, reflecting everything around them. They actually reflect the images of things with supposedly infinite definition so if you look long and hard enough, no matter how far you are on the surface of some planet close by or even in another galaxy, you will eventually be able to see yourself on its surface. Some cultures believe that if you look long enough the star will consume your soul, somewhat like in our universe, if we look long enough we can go blind. This reflective property is an effective mean of studying other galaxies and their planets and can also be used for intergalactic light speed communication as well. Despite being reflective, stars are still the light sources of the universe. They shine with the light of the images they reflect even though such images need not have their own light source in order to be reflected in the first place.
- A universe where space is porous, somewhat sponge like and it can absorb liquids into its own fabric, swelling as it does so. Wherever liquid exists in any place inside it, it is slowly absorbed into the space-time fabric and disappears from existence, until the fabric becomes filled with liquid to the point of not being able to absorb any more. At that point the remaining liquid, if any, remains in space normally. Areas where the space-time fabric have lots of absorbed liquid have a wetness feel to them. The process of absorbing is somewhat slow and happens at only a slightly faster speed than that of normal evaporation. A glass of water will be absorbed in about 20 to 30 hours, depending on how dry the space-time fabric was. If the fabric ever gets too dry there is a risk of it opening cracks into the interdimensional void, other universes or other places inside the same universe with unpredictable consequences. Over time the liquids that have been absorbed by the space-time fabric will also evaporate, although this takes longer than in-universe evaporation. As they do so, a part of them returns to the universe but a small amount is lost outside of it never to be returned. This causes this universe to be slowly loosing matter.
- Similar to the previous example, a universe where its space-time fabric is porous, only much more so, and not exactly like a sponge. It might have a structure similar to that of a sponge, filled with holes of many different sizes but it is not exactly sponge like, not having its absorbing properties. Instead, sometimes physical objects fall into one of those wholes, disappearing from reality as they do so. Some advanced civilizations may find ways to intentionally access such holes using them to hide things for example. If a living creature falls into one such hole they would probably die as the holes do not contain any life supporting features like atmosphere, water or food. They are even lacking in such basic things as light and gravity.
- In our universe light is a form of energy and darkness is the absence of energy. In our universe heat is a form of energy while cold is the absence of energy. In this universe it happens exactly the other way around. Photons are not made of light, they are made of darkness and they carry darkness around. In their absence everything is filled with light. Darkness can exist in many different wave lengths and have many different tones while light only exists as different degrees of absence of darkness. Cold comes from the movement of particles while heat is the absence of such movement. Cold radiates, heat does not. Another possibility is for both light and darkness to be opposed forms of energy existing at the same time. An anti-photon could be a darkness particle and cold could be the result of particles vibrating with negative frequencies. The absolute 0 would be a neutral temperature (possibly still considered "cold" by normal people, but that's not an exact scientific definition) while cold temperatures are negative ones and hot temperatures are all positive ones. Absolute 0 would be considered to be neither hot nor cold.
- Most universe sized creatures that have their interiors being similar to other organic living beings, like flesh, blood and bone, being made of cells and so on. An example of such creatures are the Exophages. Despite what they contain inside being entirely different from what is inside a normal, or even somewhat weirder, universe, the laws that govern its inner workings are usually somewhat similar to common laws of physics and biology.
A universe that is so strange that it would be even hard to identify it as such. It still has the essential properties of what we could call a universe, falling under its definition, having space and/or time dimensions, containing matter and energy, etc. But it does so in a much stranger way than even a surreal-verse.
- A universe where the space-time fabric itself is fluid. This can look similar to a universe that has its space filled with liquid but it is a very different thing. Other options is for space to have some type of texture or for it to be crystallized.
- Space, like matter can have multiple states or space itself can be a state of matter, much more subtle than even energy. In that case, not just matter and energy would be the same, matter, energy and space would all be the same. Matter and energy would just be a form of compaction of space.
- A universe where the location of things cannot be described with much precision. You can never know exactly where you are nor where are other things in relation to your own position. Reaching for something is always a probabilistic event. A partial example of this is the Incipiverse where this state increases with distance from a certain specific point, possibly from the observer location, but with things being much more normal close to that point. An extreme example of this can be a universe where everything inside it is omnipresent on all its space at the same time. This can be to such an extent that if location is probability based then the probability of any given thing being located in any given point in space is always equal to 1, for all points of space at the same time. This doesn't mean that all points of space are the same, such universe can still be of any size possible. It also doesn't mean that this universe exists in a state of singularity.
- Any universe that has any of its components in an undefinable or even unthinkable form, either for us or objectively so.
The word plane applies both to all the types of cosmological objects that exist at the level of a universe in general but also specifically to all such things that are not just another universe or type of universe. With the first meaning a universe is just another type of plane while with the second meaning it is not. Obviously, in this context the word is being used with its second definition.
A plane is some type of reality that exists at a similar cosmological level as a universe but that cannot be classified as a universe for some reason. They are usually somewhat magical in nature, possibly having no actual laws of physics or having just some fiat laws or apparent laws of physics but that are actually self-contradictory if carefully examined.
In the same way that these classifications can also apply to verses or cosmological objects larger than a Universe, the same applies for Planes. In that case, they are called Hyper-Planes instead, indicating their larger status. In the same way that applies to Planes, the word is used in the general case to refer to all cosmological objects larger than a universe and in the specific case just to those objects which are not a more normal type of verse.
- Things that are less than a full Universe but still exist at the same level. They are usually called Incomplete Universes.
- All things described on this wiki that are not just another type of verse, like most of those described in the Beyond Cosmology, End-All-be-All and Super Cosmology categories, if they exist at the same level of a universe they are also considered to be Planes. Things that are called pseudo-structures, meta-structures or structure-like as well as post-cosmological or trans-cosmological things and the likes. All those, to some extent, if they can be seen, rationed, abstracted as or compared to a "place", fall into the definition of a plane.
- If some of the components that make up a universe exist on their own without actually forming a universe, they are still a type of plane. An isolated dimension existing without anything else, nothing inside it, no laws ruling it, etc. Matter existing outside of any space or causality existing without the passage of time.
- Any type of virtual reality or dimension like the internet itself, virtual realities, and the likes that exist in a universe or at a similar level.
- Any conceptual, logical or mathematical spaces or sets that exist in a universe or at a similar level. Things like the Schemafield.
- The actual medium in which universes exist, like the Interdimensional Space that exists between universes inside the multiverse, as long as that medium isn't the actual multiverse but still considered to be part of it.
- Any structure that exists inside the multiverse to anchor universes around it, maybe keeping them in place, maybe stabilizing their laws of physics like is the case with the Verse Cores.
- An actual plane like a space that has a ground and a ceiling, like a huge cave without walls that goes on forever but that allows for existence inside it similar to that at a surface of a planet. It can possibly have crystals encrusted on the ceiling emanating some kind of light or maybe a small ball of fire moving through the sky at some regular or irregular schedule. There is nothing outside of its cave and if one digs enough, either through the ceiling or the floor, one either reaches an impassible barrier or ends up on the other side, with a deep enough hole on the floor opening from the ceiling, possibly directly on top of it, possibly on any other location.