Thursday, May 17, 2007

The Multiverse and Dark Matter

A half dozen years ago, when I first read in a Stephen Hawkings book about the multiverse, I was immediately struck by how it fit with my unusual way of imagining reality.

Critics of the multiverse concept like to point to this as an unprovable, undetectable fantasy masquerading as a scientific theory, something created by physicists with overactive imaginations, and embraced by nuts like me. How could we prove the existence of parallel universes? Whether you are imagining other universes that spring from other separate sets of initial conditions--other universes that have different basic forces--or whether you are imagining the extreme Many Worlds version of the multiverse that I have come to believe in, which is that every possible branch from any moment in time for every possible universe actually exists... in either case, the easy-to-ask question remains the same: if those other universes exist, why can't we see any evidence of their existence?

One of the more extraordinary claims I have made with this project is that dark matter offers us proof that the parallel universes of the multiverse do exist; and that the source of dark matter is gravitational attraction from those nearby parallel universes of the multiverse which we are constantly branching to (and from!). I believe that dark matter proves that there is more out there than just the single observed universe of hard determinism that we see around us from moment to moment.

Energy and mass are directly related, two sides of the same coin, as Einstein demonstrated. But according to modern science, only four per cent of the universe is accounted for. 73% of the universe is dark energy (the unexplained force which is now causing our universe to accelerate apart from itself), and 23% is the "missing matter" whose gravitational attraction has kept the universe from flying apart as quickly as we would have expected it to, based upon the gravitational attraction of that visible four per cent. So, as I have discussed before, we find ourselves to be living in a “lucky” universe, where the initial big bang conditions created just the right balance between mass and the value of the gravitational force to create a universe which did not immediately collapse in upon itself, or did not immediately fly apart without allowing any significant matter to coalesce.

In a previous blog, I mentioned that experts such as Kaku, Greene, and Randall have told us that of the four basic forces (from weakest to strongest those are gravity, electromagnetism, the weak nuclear force, and the strong nuclear force), gravity is the only one that travels across the dimensions. In other words, those other three forces are rooted to the structure of matter within our fourth-dimensional spacetime, while gravity is part of the more basic underlying fabric from which spacetime is constructed. A reader of that previous blog commented that they disagree with this idea because the energy of thought and spirit can also travel across the dimensions, something that I happen to agree with, but here we are talking about what hard science believes about forces and dimensions.

Here's what I say in my book about this idea:

If gravity exists in the fourth dimension and above (which is the current belief of string theorists), doesn’t that mean our new way of viewing the ten dimensions offers a much simpler explanation of dark matter? If all other possible timelines do really exist, then isn’t it conceivable that there will be a certain amount of gravitational pull from the fifth dimensional paths that are most adjacent to our current point in time, with the amount of “gravitational leakage” diminishing as we travel further away on a different fifth-dimensional path from our own fourth-dimensional line?

At any moment in the history of the universe, the number of future paths available to be chosen out of the quantum waves of indeterminacy will be the same. This is not to say that some paths won’t take on substantially more significance for us as a species or for each of us as individuals, but rather that the sum of all available choices that are available will always be the same, which is why the “dark matter” gravitational pull our universe experiences does not constantly fluctuate up and down.

Plus, as we’ve already discussed, Feynman’s “sum over paths” concept tells us that there are an equally large number of paths which could have been taken to arrive at the current moment, even though each of us are aware of only one of those paths. This means that the picture we’re now imagining has an equally large amount of “gravitational leakage” that would be coming from those paths as well. This concept helps us to imagine how the gravitational pull from those other dimensions is not just pulling us forward in time towards the many branches we could be about to take, but is also coming from all of the paths which could have been taken to get us to any particular moment on our fourth-dimensional line.

In my personal opinion, this is the most exciting confirmation that the ten dimensions as we are imagining them here could truly be connected to the structure of reality–in this context, dark matter has a simple explanation. All we have to do is accept that time is a spatial dimension rather than a quality that we overlay on the other dimensions.

One of the verses of my song "The Unseen Eye" talks about this same concept:

And the missing dark matter that binds the universe
The mysterious mass that science cannot find
Is in the many worlds of possibility
That are just around the corner in time

Here is a link to a previous blog which prints all the lyrics to that song. And here, for fun, is a video of that song:

A link to this video can be found at

Coming up: "Ghosts and Intuition"

Enjoy the journey,


Tenth Dimension Vlog playlist