## Sunday, December 30, 2007

### FAQ 3 - Why Ten Dimensions?

3. Why ten dimensions and not some other number?

One of the common arguments surrounding this concept is a presumption that ten was arbitrarily picked, perhaps because we humans have ten fingers so we like the number. Some people prefer the idea that there are infinite dimensions, some people say there is really only one dimension (our physical reality), and of course some people have their own specific interpretation of the word "dimensions" that disagrees with other interpretations, which can also draw them to conclude that this project is not about dimensions at all. Here is a blog entry that discusses this project's use of the word "dimensions", and here is a blog entry which shows how this way of visualizing agrees with the most basic definition of that word from wikipedia.

Three
Some believe that three-dimensional space is the only thing that qualifies for the word "dimensions". To their way of thinking, time is not really a dimension, it's just a quality that is overlaid on the first three spatial dimensions.

Four
Most of us are used to the idea that space is three-dimensional, and even that spacetime can be thought of as four dimensional, but some are not willing to say that time is a full spatial dimension. Here is a blog entry about that idea. Entries like "Time is a Direction" and "Hypercubes and Plato's Cave" also explore this concept.

Five
Some prefer to use the term "spacetime tree" to refer to what we're talking about here, and even those who use that term are not necessarily imagining anything more than the fourth dimension. From our big bang, at both the quantum and the macro level, there are a branching set of probabilistic outcomes, only one of which we are currently within. We look back in time and see a straight line of "time's arrow", which this project says is a line in the fourth spatial dimension. The only place where the entire spacetime tree for our universe is available is at the first instant of the big bang (or, within the Information Equals Reality paradigm, the very first step of the selection process that differentiates our universe from any of the others having different basic physical laws). From there on, certain probabilistic choices are no longer available because of previous outcomes, which is why our line of time does not wander into the parallel versions of our universe where it's 2010 and dinosaurs aren't extinct (for instance). The idea that the higher dimensions are invisible to us because they are "curled up" down at the planck length is completely compatible with this way of imagining reality. Different blog entries discussing the fifth dimension can be found here, here, and here. Other popular blog entries about the fifth dimension include "The Fifth Dimension Isn't Magic", "The Fifth Dimension is a Dangerous Idea", and "Your Fifth-Dimensional Self".

Six
The sixth dimension, would be where we would find all possible branches for our spacetime tree, including the branches that are currently unavailable to us from our fifth-dimensional probability space because of what has come before, and those upcoming branches that we choose to never witness (like the branch where I stop typing this entry and run down the street naked instead). Blog entries discussing this way of imagining the sixth dimension can be found here, here, and here.

Seven
Seven is another number that commonly comes up for the highest imaginable layers to our reality, and the way of imagining reality that we're exploring here does indeed assign a special significance to that number. Here is a blog entry about that idea. As an aside, it does seem significant that string theorists are proposing that our universe is created from the interactions of a three-dimensional brane with a seven-dimensional brane.

Eight
According to this way of imagining reality, eight is most likely the highest dimension that can contain any physical expression of matter. In late 2007 a new theory deriving the basic forces and particles of our universe from an E8 matrix received favorable attention. Here is a blog entry playing with some ideas surrounding that discovery.

Nine
Some people who have stayed with this line of reasoning up to here have said that nine is really the last full dimension, since the tenth is only a point of indeterminate size. Since that point is the unobserved whole of every possible expression of matter and energy, of the information that potentially equals our reality, and it encompasses every possible expression of the dimensions below, I'm standing by my claim that there are really ten dimensions, but I understand why some think I'm bending the rules a bit as I get to the end. My blog entry "You Can't Get There From Here" talks about these ideas, as does What's Around the Corner?.

Ten
String theory says there are ten dimensions. M Theory says there are 11 dimensions, but one of those dimensions is time. If we can accept that time is not a dimension but the way you move from one state to another in a specific dimension (whichever dimension you care to examine), there is a way to fold all these ideas together. The fact that mystical systems like Kabbalah also assign a special significance to the number ten may be coincidence, or may be because of what I'm talking about: that eventually we are all going to arrive at a meeting place where science, spirituality, and ancient wisdom will be shown to be talking about the same things. Wouldn't it be far stranger if, when science finally comes up with the grand unified theory of everything, there was not something that felt intuitively right to us about those revelations, since we are participants within that reality?

Finally, here is an embedded player which should allow you to listen to a 47 minute interview conducted with me by Tom Huston, Senior Associate Editor of EnlightenNext Magazine, which gets into more of the arguments for picking ten as "the" number.