# 4D Universe

This post is a follow up to the last one about the 4^{th} dimension. There are so many ideas explored in *Surfing Through Hyperspace* that I felt it better to write two separate post about it. The 4^{th} dimension is such a bizarre idea and concept yet at the same time in the math world it is nothing out of the ordinary.

Many of the most interesting ideas in the book were the 4D beings themselves along with a 4D universe. Everything about both topics are pretty much pure speculation but some of the speculation is based on math so it is believed to be true even though we have never observed it.

In a 4D universe planets would not hold and elliptical cycle around their stars. They would always be flung back out into space. The reason for this is the lack of gravity in a 4D universe. What I have read is that as the dimensions increase gravity decreases at an exponential rate. The reverse can be said of the lower dimensions, as they decrease gravity increases. So a 2D world would have stronger gravity than our own. This has been proposed in the early 1900’s and recently proven to be correct. There are mathematical formulas out there if you are interested.

So the question is, if that is the case then how can intelligent life, or any life for that matter, exist in a universe where planets float freely in deep space and have such low gravity? This is not to say that life is not possible just very improbable. The book also talked about how basically the ideal universe will have one time dimension. If there were more than one time dimension in a universe it would cause all sorts of problems. Like if you were to meet someone at a specific place on your planet, given that both individuals were on the same time, when they met they would still slowly be pulled away from one another because of the other multiple time dimensions. I am not sure exactly why this happens, the book did not go into a lot of detail on this idea. So I think it is safe to say that life in a 4D universe has an almost 0 probability of existing. To me, and I am neither a astro-biologist or a physicist, there seem to be way too many basic problems with the universe to ever allow life much less a planet that circles a sun to capable of supporting life.

That being said if there were beings that came to call a 4D universe home what would they be like? Some believe the beings would be highly highly intelligent, on levels we could not even comprehend. In fact they would have senses that are far beyond our comprehension as well. The book goes on to discuss other things like a digestive system of a 4D creature as well as a nervous system. This part of the book is very interesting, and because they are speculation they rely on what we already know about 4 dimensional objects. For example a 4D object has a larger surface area than what is inside it, or at least that is what I understood. So they claim that a 4D person would have more organs closer to their skin instead of deep inside their bodies, simply because of the lack of room. Simple concept, makes sense, but I think that evolution does not always make the most rational decisions, still it is interesting to think about.

The book also discusses the fact that we cannot see into the 4^{th} dimension and why that is. Our retinas are 2D, and the book claims that we would need a 3D retina to see the 4^{th} dimension among other things. That also assumes that our brains would be able to process the information the 3D retina would be sending to it. Basically to see into the 4^{th} dimension we would need a major overhaul biologically speaking.

The other interesting idea that the book talks about is that maybe the 4^{th} dimension is an escape route for beings from our universe or other universes. Our universe will eventually end and when it does what happens then? Maybe all the superior technologically advanced beings will have already escaped to the 4^{th} dimension and will be safe while our universe is destroyed. I know it seems farfetched but it’s just an idea.

Another possibility is that maybe the 4^{th} dimension is the only way to travel large distances in our universe. Perhaps we are thinking about traveling cosmic distances in the wrong sense. We are trying to go faster, or as close as possible to the speed of light, but what if traveling a great distance was as easy as jumping into the 4^{th} dimension and at the snap of a finger you are there. Think about this, draw a square but leave one side with a small opening, basically a door way, place a small circle inside the square, one that can fit through the doorway. This circle represents a living person on paper world. Now imagine your paper as a vast plane and on the opposite side of the square form the door is a friend you are supposed to meet, another circle. So now to meet your friend you have to exit the square, through the doorway, and travel along one of the sides and around the corner to meet your friend. Well what if you could simply jump into the 3^{rd} dimension. All you would have to do is jump the wall opposite the door and whala you are there. What if each side of the square were a mile long or longer, but even at a shorter distance simply jumping into the 3^{rd} dimension, over the wall, will get you there almost instantly. I would assume that this idea will hold when speaking about the 4^{th} dimension and large distances in our own universe, so maybe that is how it is possible to travel vast distances in our universe without rewriting the basic laws that govern our universe. Regardless we do not have the technology to do either, but again maybe we are looking at the problem the wrong way.

So much to think about…

Manik