|Stephen Hawking and Kip Thorne|
...it seems likely...that our universe is a membrane (physicists call it a "brane") residing in a higher-dimensional "hyperspace" to which physicists give the name "bulk"...Later on, in Chapter 22, he speculates on what it would be like to be an awareness residing within this "bulk":
If there are bulk beings, what are they made of? Certainly not atom-based matter like us. Atoms have three space dimensions. They can only exist in three space dimensions, not four. And this is true of sub-atomic particles as well. And it is true also of electric fields and magnetic fields... and the forces that hold atomic nuclei together.
Some of the world's most brilliant physicists have struggled to understand how matter and fields and forces behave if our universe really is a brane in a higher-dimensional bulk. Those struggles have pointed rather firmly to the conclusion that all the particles and the forces and all the fields known to humans are confined to our brane, with one exception: gravity, and the warping of spacetime associated with gravity.
So. The world we see around is confined to a 3D brane, but we need the fourth dimension to change from state to state, and Thorne embraces the idea that there is at least one more dimension, a fifth dimension, with which we could be interacting. Beyond that he acknowledges that this extra-dimensional "bulk" probably exists, but as we quoted him to say last entry, "for practical purposes, the number of extra dimensions is really only one".
Confusing? Here's a few key points to keep in mind. If we're talking about our observed reality being derived from ten dimensions, then it's impossible to consider any one of those dimensions without also acknowledging that they are connected to each other, and that each dimension has to be considered a subset of the additional ones if we're going to be consistent in our logic. So the 3D membrane of our universe resides within 4D space-time, which resides within the fifth dimension, and so on. Each additional dimension adds another degree of freedom, a way to get to states not previously accessible, until we get to the place where the potential for every possible configuration exists simultaneously. Reducing the number of dimensions being considered, then, has to represent a paring away, a reduction in possibilities that occurs incrementally as each dimension is removed, and would be a way to see how some other universe with different physical laws could exist within its own unique version of the third dimension: just as real as, but completely inaccessible from, our own version of the third dimension.
This is what's so powerful about the point-line-plane postulate: it gives us a way to start from our universe of three space dimensions, a universe already absolutely mind-boggling in its size and complexity, and visualize how that is only a tiny slice of the possibilities being added with each additional dimension.
Who's There to Greet Me When I Die?
Your Sixth-Dimensional Self is one of my earlier blog entries, from back in July 2007. Here's how I concluded that one:
What does timelessness mean for me? Because time is an illusion, it means that once any of us breaks out of our physical reality, there we will find all the other branches of our sixth dimensional selves, waiting to greet us and compare notes on the journey, and see how everything fits together.Do you see how this relates to some of Interstellar's more "out there" implications we explored a few weeks ago in Interstellar and Pendulum Clocks? Each of us, when we stop to think about it, must have near misses that could have turned out much worse, minor accidents that could have been major. Everett's Many-Worlds Interpretation of Quantum Mechanics proposes that all the other versions of the universe where the other different probabilistic outcomes occurred actually do exist, they're just not part of the current version of the universe we're observing. So each of us already have died in some of those previous near misses we can look back upon from today.
If there are ways that awareness can continue on after death, then it stands to reason that the versions of me that were not so fortunate in those past events might still be interested in following along to see "what happens next". So here's an interesting thought: we hear from psychics and near-death researchers all the time about the loved ones that will be there to meet us when we die. But wouldn't it be likely that one group waiting to meet with us, and compare notes on how lucky we were to have lasted as long as we did, be the other versions of ourselves that had already died? What a reunion that would be!
To conclude, here's a video from early 2009 in which we look at some other ideas related to imagining ourselves as viewed from the extra dimensions beyond space-time: "You Have a Shape and a Trajectory".
A direct link to the above video is at https://www.youtube.com/watch?v=zlZAMtmHkKg
Enjoy the journey!