"In mathematics and physics, the dimension of a space or object is informally defined as the minimum number of coordinates needed to specify each point within it"
We like to say that the world consists of 3 dimensions. The talk of "dimensions" is very confusing and almost seems to suggest that one can experience less or more of them but that we humans happens to live in the 3 of them. We call them X, Y and Z and some of us even imagine beings living in just X and Y. But X and Y is inside X, Y and Z so any being existing in X and Y would have to exist somewhere in our 3D space, like on a sheet of paper! But even a paper is 3D, so basically there is no "2D world" or "1D world"...
A fourth dimension would represent duplicates of a 3D space a fifth duplicates of all those duplicates and so on. And all the 3D spaces inside this mess would be separate from each other! That's what would happen with more dimensions! Yet we like to talk about them like they mean something else...
Time as a dimension
If time was a fourth dimension this would mean that there were duplicates of our 3D spaces where time is a coordinate defining one of them. Which actually makes all those 3D spaces STATIC without movement, just like a frame in a movie.
So what does this make time then? A force which duplicates our 3D space whenever a physical reaction happens? Which means more and more 3D spaces are always created but we only perceive the last one of them?
Or are all those static 3D spaces already there but our consciousness traveling along them?
If one believes in "time" as a fourth dimension feel free to wonder about this (and a fifth dimension could represent alternate timelines by the way). But personally I don't think time should be looked upon as a DIMENSION!
Why? Because I don't think time is a coordinate!
It might help our mind thinking of it as a coordinate, but that doesn't make it so! Time is just a variable defining the speed of physical reactions! And I've shared some of my thoughts about "time" in my previous blog post.
Back to "dimensions"...
We hear scientists who like to throw that word around, but do they even themselves know what it is? I personally think it is a very misused word!
And I don't think that everything has to be explained as being "within a dimension"! Often when talking about dimensions/coordinates they have infinite values, X, Y and Z in our universe can't be said to have any max value for example. But what if we have a fourth dimension with only 10 values? How many values does the different dimensions have?!
Dimensions are just a way to represent things and I don't necessarily think that everything can fit in such an representation!
I think "layer" is a word that should be used more often!
If you've used Photoshop (or any other image editor) you have an idea about what a layer is. Of course one might also call that a fourth dimension, but let's avoid that word for a moment.
Since electromagnetic waves can travel through vacuum I like to believe that there is a layer of electromagnetic "fabric" or "potential" which is like a quiet sea. But when one generates an electromagnetic pulse it is like dropping a stone into this sea, so the signal will travel NOT "in it self" but in the sea of electromagnetic potential. The point being; we could have stuff going on in different layers but which exists in the SAME space!
Maybe we have a physical layer which interacts with an electromagnetic layer, and so on. And we can measure the EFFECT of the electromagnetic layer interacting with the physical layer, but not the electromagnetic layer itself. And notice how we can describe all this without having to use the silly word "dimensions" and trying to understand how all of this would fit in the "dimension theory".
So stop throwing the dimension word around people!