In the first book of C. S. Lewis’s acclaimed The Chronicles of Narnia series, the main characters Diggory and Polly find themselves in a strange wood. This wood, called the Wood Between the World, is filled with pools that lead to another world. By wearing a special ring, the children hop into the pool and descend into another universe. (Yes, I’d tried that countless times and ended up miserably soaked in the muddy puddle.)
But what does that have to do with science? Isn’t this more…magical? True, my friend, that is quite true. Yet I couldn’t help but think, “This is a whole lot like the dimension theory I’ve read about.”
So the first thing you probably want to know is, “What is a dimension?”
1: What is a dimension?
According to Merriam Webster, a dimension is:
- (In mathematics) A measure in one direction
- (In physics) The quality of spatial extension
But that’s kind of rather vague. What does it really mean?
Well, the easiest place to start is by thinking of a dot. If you keep connecting a dot, it soon becomes a line. That’s the first dimension. So, in a way, a dimension is a certain point on a line.
The second way to think of it is to gather the lines created from a dot. By crisscrossing the lines, you soon have a plane or a sheet of lines like a piece of paper. When you draw a circle or a triangle, that too is on the second dimension as long as it has no depth. This is the second dimension, which you see often in math as the x-y plane.
The most common way we understand a dimension is by 3-D. When we catch the ball tossed to us’ or when we drop that addictive rectangular prism known more commonly as phones, we are in contact with the third dimension. Now it has depth to it. On a mathematical plane, it would be described as the x-y-z plane.
2: How many dimensions are there?
(If there are multiple dimensions, how soon can we travel in them?)
Setting the joke aside, do you sometimes wonder if there is a world exactly like ours? It’s entirely identical–except in that world, egg tarts do not exist.
In addition to writers like C. S. Lewis, Haruki Murakami, and V. E. Schwab, scientists have also tackled the question of parallel universe and multi-dimensions.
As of now, most people believe in classical physics having three dimensions. (Some people say that time is the fourth dimension, but that’s not entirely true since it’s not really a spatial dimension.)
In the superstring theory, there are multiple dimensions (up to eleven!!!), strings (or vibrating string-like particles that everything consists of), and membranes of energy (called branes for short). Ignoring the long list of names that evolved as the superstring theory, this theory states that everything in a reality is actually a string that vibrates at a certain frequency. With this theory, scientists literally tried to tie together the problem of general relativity with quantum physics. And to support this, they round the theory up with three physical dimensions (the ones we can see), time, and six unperceivable dimensions (which are the alternate dimensions). The only thing we should note is that there isn’t much evidence to support it, partly because we can’t measure the rest of the six dimensions properly.
But to say the least, many physicists are rather hopeful about the possibility of having multi-dimensions. It’s even probable that we might find a parallel universe! So the Woods between the World is only half-fictional…it’s just that we have no manner of understanding the ninth dimension, yet.