# How would a higher-dimensional being enter a lower dimension?

So I could not get any answers for my previous question regarding what happens in a indeterministic world such as the worlds in a Cauchy Horizon of a Reissner Nördstrom Black Hole.

However, I deduced from one of the comments that a world beyond time, and beyond where both space and time in one universe is compressed into one single origin, this "indeterministic universe" is essentially a higher dimension, where time is reduced to a physical constant in the eyes of a higher-dimensional being, or simply of lower existence altogether.

Which thus prompts me to wonder how a higher-dimensional being would interact with a lower dimensional world, which I mean entering it directly, rather than manipulating it from higher dimensions. I use the classic bulk theory, where our universe could be just a 2-D brane in this higher dimension. Would it fall inside the bulk? Would it make wormholes?

• Our four dimensional universe cannot possibly be a two dimensional anything. If you need four numbers to identify a point you need four numbers to identify a point; three won't do, and two is right out. – AlexP Jun 10 at 10:01
• @user6760 - 2007... film...? The novella Flatland was originally published in 1884. – Dave Sherohman Jun 10 at 11:15
• They take the form of mice. – The Daleks Jun 10 at 11:48
• @user6760 I don't think anybody's questioning that there is a 2007 film, it just feels strange to recommend that over the far older and more widely-known book. Like if I were speaking to someone unfamiliar with Star Wars, and I told them to check out Star Wars Episode IV: A New Hope, the 1976 novel by Alan Dean Foster. – Josh Eller Jun 10 at 18:00
• @wwarriner Actually, having watched both films, I was saddened how far they both are form the excellent book. Neither do a good job of explaining the basic point, although the shorter one was slightly better in that regard. Either way, the book is way, way better, especially if you want to understand this stuff (as opposed to just watching a fairly boring film) – Avrohom Yisroel Jun 11 at 15:49

In short, a higher-dimensional entity does not "enter" a lower dimension, it passes through it.

Consider a planar (two-dimensional) universe. If you or I were to interact with it, we could stick our fingers through it, with a cross-section of each finger intersecting that plane and existing within the planar universe at any given time, but we could never fully enter it without somehow flattening ourselves into two-dimensional entities - and somehow surviving the process.

Note that this example also illustrates how we could seem to exist in multiple places simultaneously in the perception of the planar entities, as each finger intersects the plane at disconnected locations, despite being connected at a location outside of the plane. And our forms would shift in that planar universe as the fingers moved through it, widening and narrowing in the intersecting slice, until the bulk of the hand reaches the plane and all fingers expand and merge into a single larger planar entity.

You would do well to read the 1884 story Flatland (which is now in the public domain and can be read in full on wikisource), which further explores these ideas.

• In other words, you could get back in with a little push, but you might not even be the right size anymore. – CYCLOPSCORE Jun 10 at 11:27
• This how the way they perceive you might Change by a lot simply because the entirety of you can't be fit into their plane at once. I'm pretty sure some creatures from Lovecraft's novels had a similar interaction with humans (except that'd likely be closer to a 2d person suddenly perceiving the entirety of our 3D form). – ProjectApex Jun 10 at 12:02
• So Outer Gods are Outer Gods just because that's how they should be, and not just because of their physiology? – CYCLOPSCORE Jun 10 at 14:04
• @CYCLOPSCORE People of a higher dimension are gods because they have great power over our world. Imagine people walking about on a piece of paper before you. From their perspective, you have many powers they cannot explain. You can draw and erase objects. You can observe the entire universe at once. You can even (using scissors) add and remove pieces of the universe! – Just'Existing Jun 11 at 2:04
• Not only can you observe the entire paper universe at once, you can effortlessly see what's inside of a sealed box, or look into the guts of a planar entity - they have no way to hide anything from you. – Dave Sherohman Jun 11 at 8:03

By proxy

It would be terrifying to enter a 2d world. But we do it all the time in video games and it is fun, because we have a tech interface that interprets a 2d world in a way that make sense to us - the original DOOM is a fine example, or PacMan. A number of games attempt to render 4 spatial dimensions on the 2d monitor screen. The video game Braid takes a 2d Mario-type world and introduces time as a manipulable 4th dimension.

We use probes, cameras, scopes, remotes and technological proxies of all types to interact with environments that are unsuited for our physical bodies. So too your superdimensional creature wishing to interact in a meaningful way with lower dimensional worlds. The tech proxy would interpret that world in a way that made sense to the creature, and if desired the proxy could be made such that it could interact with the denizens of that world.

• This higher-dimensional being will also take on a title or name for its proxy or "avatar". A simple name which the denizens of the lower dimension can comprehend, like "Mary-Sue". – Jedediah Jun 10 at 19:07

From a purely geometrical perspective, be n the number of dimension of the higher dimensional being, let's call it N, and k the number of dimension of the lower dimensional realm, let's call it K, N will interact with K as a k-dimensional cross section, like it was brilliantly illustrated by Abbot in Flatland and by Vonnegut in Slaughterhouse 5.

In particular, following Vonnegut, a higher dimensional being could see what for us is the time flow as a solid of which we see only a slice at every moment, and might find questions like "why did X happened?" rather silly, being forced to answer "because it was structured in that way"

Beings from higher dimensions may be projected onto lower dimensions:

To view beings from higher dimensions, a suitable projection surface is needed. This might lie within "gifted" persons, who have the ability to "view" higher-dimensional beings through an internal "mental screen" unique to them. It could also be a "ghost", "mirage", or "phantom" that the being itself effects in the lower dimension (in the way that video can be projected onto fog or smoke).

• Or there's the natural intersection. Hypersphere > sphere > circle > point. For each level the next up is conceivable in the sense that you can imagine an ice cube melting over time, each "moment" a perceptual frame. – Peter Wone Jun 12 at 4:56

I'm not sure this falls within the scope of answers you're looking for, having tagged your question science-based so maybe oriented more towards what we can model mathematically (though not all disciplines of science are about mathematical modelling). Anyway, with that out of the way:

Makes me think of the way God packed up the essence of himself in a tangible human person by the name of Jesus Christ.

I don't think I can cover even most important aspects here (and some may be well beyond the scope of your question proper) but I'll mention that we can observe here

• a person apparently fully out of this world, interacting and being interacted with by the people around quite normally (save the extras, come to that in the next point) and being perceived as one of them (even to the extent that some are adamant about that)

while as things develop, we see a meaningful number of the people, as they encounter that person, discovering that

• there's a lot more to that person than what's visible at first sight, and a connection with a reality that obviously goes way beyond what people are used to.

So we can go from here and make observations on what happens to, with, and from the person from the higher-dimension system and how it plays out to and in the lower-dimensional system.

It's interesting what possibilities this offers for interaction and how the interaction goes on here. For one, that connection with the higher-dimensional reality (to name it in terms of the question) is obviously not forced on the people around - as we see some bluntly ignoring it - while we can tell from the fact that we see others interpreting it to be of whatever nature and source they like to think of, that there is something going on that is hard to ignore without choosing so.

It can further be observed that the person immersing in the lesser-dimensional world is fully at liberty to reveal of his true nature as little or in fact as much as he chooses to, only limited by the degree to which the individual people are capable and willing to understand (or may be helped to understand by the person revealing).

Which in this case leads to an amazing and, in some dimensions (including what some would call metaphysical), even total extent of interaction with some who agree to it.

As for some other points of your question, there seems to be no falling into wormholes or similar involved here, rather a kind of total control of the overall reality including the parts of it that are perceivable in the lower-dimensional space - while most aspects of it are generally left untouched (and the same obviously goes for the freedom of the people around to be doing what they choose to, but that's outside the scope of your question).

So to add this angle, there is no falling into a wormhole of any elements of the lower-dimensional system either (albeit there is some access to aspects of the higher-dimensional system as provided by the person immersing).

• @CYCLOPSCORE (sorry cant comment under your own question as yet because rep) May we trouble you to edit in a link to your previous question regarding what happens in a indeterministic world such as the worlds in a Cauchy Horizon of a Reissner Nördstrom Black Hole in your question? As for now if I didn't overlook it I could only find it either using Search on a careful selection of the key words or by going all the way through the All Questions mode of your user profile sorted by Newest. Either way is rather a number of clicks to get there. Sorry for the interruption. – somebody_other Jun 11 at 17:31
• On a bit of a an extra-dimensional meta note: The above is an excellent and healthy use of comments! – newcoder Jun 13 at 15:36
• Hey, @newcoder Hi and thanks for the feedback and encouragement! (On a meta note, I do confess I haven't gotten around to finding out whether saying that is, too.) – somebody_other Jun 13 at 23:28

By a projection.

A projection is exactly mapping something to a lower dimension.
For example, when you map a cube in three dimensions to two dimensions, you have a square.

Of course, there is something lost in the projection - but that is the whole point of removing dimensions. But if something specific is lost that should be retained, you could choose a different subset of dimensions to project to.

Ant and large Stone! An ant when it roams around a stone always sees only what is around it. It does not have a sense of curvature or texture of stone. For the Ants, the irregular surface of the stone will just look like a plane area to roam around.

• I see the analogy, but it's not quite the same. – Mad Physicist Jun 12 at 1:37

In Liu Cixin's Three Body Problem Trilogy, this is treated two or three times.

WARNING: There will be spoilers about all the three books regarding technology development, society development and plot. It's the only way to answer this question using this source, so they won't be hidden.

-In the first book, the Trisolarians make sophons from

a proton that is unfolded from eleven dimensions into two dimensions, then programmed and refolded. (source)

-In the third book, the tripulation of the Blue Space discover a zone of space that is a remaint of the previous 4 dimensional universe. They also encounter a ring that tells them that there are some beings that try to survive in lower dimensional spaces and eventually achieve it.

Near the end of the third book, the Solar System is reduced to a 2D space. However, it is implied that, should they exist, lower dimensional beings can get to greater dimensional spaces, altough they are a lot more easily damaged, because there can be micrometeoroids that can come in a lot more directions.