Our universe, as we know it, has three dimensions of space, length, width, and height, and one dimension of time. But according to String Theory, there may be many higher dimensions out there that are so tiny that they are very difficult for us to detect. Some versions of String Theory, such as Bosonic String Theory, predicts as many as 26 dimensions. But the number of dimensions decreases significantly under newer versions of the theory. For example, Mtheory requires 11 dimensions, while Super String Theory requires only 10. But what are these higher dimensions, and how might we experience them given our limited awareness of only the three spatial and one time dimension? Well, today, we will be looking at what physicists think these higher dimensions might be like!
When trying to understand higher dimensions beyond the 3 physical ones that we are used to, it is important to build up from the very beginning. Let’s start by imagining a point indicating a position in a system. It has no dimensions because it has no length, width, or height. Next, imagine a second point somewhere else in this system. The line joining these two points at a right angle gives rise to the first dimension or the length. Similarly, taking two copies of the line and joining them at right angles to each other would define a plane with both length and width, giving rise to the second dimension. Now taking two copies of these planes and joining them at right angles to each other would result in a 3D space, having length, width, and height, that we are all so familiar with. Now, geometrically, we can keep this process going and get higher dimensional versions of various shapes, or at least their shadows onto our 3D plane. But what would it be like to experience and exist in these different dimensions? Let’s build up from the zeroth dimension.