[DearMandy (OP)]

So ... I posted this up in some weird Facebook group I'm in and now I'm on the hunt for more input and consideration. 

I also got a really informed and intelligent reply, but one is not enough and now I gotta see from the author if I can share their reply. 

Anyway

I just want to pop an idea out there just for a moment and see what a bunch of students and hopefully their teachers might think on it and tell me if I'm nuts or not. We always talk about about higher dimensional spaces casting their 'shadows' down to our lower dimensional spaces to create these shadows that allow for less complex forms of matter and energy. Many believe that a fourth dimensional star collapsed to form our universe and that fourth dimensional 'shadows' are what allow for our third dimensional reality. What if its the other way around? What if its that lower realities have been evolving and evolving to produce higher realities? Like each manifestation gets slightly more complex till it adds a new dimension. So maybe, and this is an affront to the idea the the laws and variables are similar enough in different dimensions to say that stars form in all of them, but what if a increasingly complex two dimensional universe had a star collapse and die that birthed a very simple three dimensional universe?

[impyre]

I had a similar idea a few years back. I imagined that it started with one dimension. Of course, when you're speculating about things existing outside our universe there's little else you can do except speculate. And the thing about speculation is that it can be neither wrong nor right. No idea can be "too crazy" or "too weird". Honestly, we know nothing about what existed before (or outside) our universe, if anything. It could be equally plausible to argue that our universe is simply an accident. Some beings on a higher plane developed a new technology to take advantage of limitless energy supply. This machine creates pockets of extra-dimensional space somehow contained in a small package, and this package gives off massive amounts of radiation. What they don't know is the source of the radiation appears to be a process of a physics interaction in their universe, perhaps on their version of the "quantum level", but really it comes from our big bang. The reason entropy always increases, the reason for dark matter and why the universe is expanding. It's all because we're a cosmic battery powering some higher dimensional child's toy.

You could say "Aww, that's all absurd rubbish and total crap." Of course, you don't know any more than I do about what exists beyond our universe. And since we have no basis for reference, we can't even surmise what's likely or unlikely. It's honestly a total crap-shoot. (Edit: by crap-shoot I mean totally random, unpredictable, unknowable, etc)

[DearMandy (OP)]

I got this reply posting up about it elsewhere.  The person who gave me this reply goes by the name of Bosner.

Great question. I think there are two ways to think about your question: 1) higher dimensions emerging from lower ones and 2) lower dimensions affecting higher ones.

1) I am willing to be told otherwise but I think that based on what I know as a non-specialist in this area that you can't have emergent 4th dimensional properties forming from a 3 dimensional universe. Using holographic theory as the basis of my answer - you can't generate 4th dimensional information within 3 dimensions, you have a maximum amount of information 'storage' in other words. In order to project 3 dimensions from 4 dimensions new information would have to be generated and I know of no mechanism for this.

2) However, if the higher dimensions do exist already then although we have no mechanism to do so now, there is speculation as to whether we can manipulate higher dimensions. For example, a key theory as to why gravity may be so weak compared to the other forces is that it permeates multiple dimensions. As we learn more about gravity we may be able to manipulate it. It sounds like sci-fi but there are several schools of thought on this right now with multiple research fronts in each. Some think it may be the key to interstellar travel, for example.

As for the star formation and collapse part of your question I would have to hold my hands up and say I have no idea whatsoever. I would presume that as gravity plays a part in star formation and destruction then there would be some kind of trace of stellar information permeating all of the other dimensions by as for what this would look like is beyond my maths.