We live in a four-dimensional world which comprises length, breadth, height and one dimension of time. But in recent years, string theory, which claims to unify all the four laws of physics, has brought up a very engaging idea stating that there might actually be more than just four dimensions. String theory has got us thinking that we might actually be living in a ten or eleven dimension world. For those who don't know, string theory states that quarks, which make up protons and nucleons are further made up of tiny strings which vibrate at different frequencies causing the property of the substance. But the mathematics of string theory does not work in our 4 dimension world. The reason is that in three dimensions the strings won't have enough room to wiggle and bring about the unique property.
But people often ask why ten or eleven dimensions. Why not more? Well the answer is because we got some magic numbers in mathematics which have spectacular properties and it turns out that if you go to a 12 or higher dimensional universe its unstable particles would prefer to collapse down. So it's basically ten or eleven dimensions we are interested in. But this idea has divided people with the majority agreeing that it's just some vague unprovable and an impossible idea. People often relate higher dimensions to science fiction but it's no longer a plot of a 100 million dollar sci-fi film. It's the new talk of the town and has left scientists contemplating our complete understanding of the universe with many seriously believing that it might actually be the new true reality.
What is the basic concept behind these extra dimensions (hyperspace)
Consider a desk with a flat surface on which you start tiling paper side by side. Eventually you would run out of space. You have exhausted the surface of the desk, but we have got substitutes to solve this problem like a page organizer. Now when you have exhausted the two-dimensional space of your desk, you could add a page organizer and enter in third dimensions and put the pages there. Now if you are an ant embedded in the second dimension surface of the desk, and someone fills up the desk with pages tiled side by side, the ant would say “There is not more space” and I say yes, there is and I take few pages from the surface of the desk and add it on a page organizer. For that ant the pages have disappeared into a dimension the ants don't have access to. Access to a third dimension is an extraordinarily useful storage device for a being in two dimension.But consider another scenario where we run out of page organizers to arrange the pages on the desk. We would say “ we have run out of space and the only substitute is the switch to another table but an alien watching us says “wait a second i got it!” and he takes the pages and puts them in the fourth dimension. This time For us the pages have disappeared but they are actually in the fourth dimensional world. That's basically the logic behind extra dimensions. They exist but with our current methods and technology we are unable to detect them. It's like a fish swimming in a pond which can only move forward and backward. For it, it is living in a two-dimensional world and has completely no knowledge of extra dimensions and the world outside the pond but above the pond there are extra dimensions which it was not aware of. We think we are the fish swimming in a pond of obliviousness.
What do these extra dimensions look like?
A dot on a paper has no dimension as it has no height, width and length. A line drawn has one dimension which is its length. A square has two dimensions, length and height. A cube consists of three dimensions, length, breadth and height. A line is one-dimensional, but it is bound by two points. A square is two-dimensional, forged out of four one-dimensional lines. Similarly a cube which is three dimensional is made up of six two dimensional squares. So the pattern currently is two, four, six. Now let's go up to a fourth dimensional shape. A four dimensional shape which we call a tesseract, has eight sides and each side is made out of a cube! Our brain has a very hard time imagining extra dimensional shapes, like the fourth dimension made out of eight cubes, after all we were born in the lands of Africa with the sole aim to survive. Currently, we don’t know what a ten or eleven dimensional world truly looks like. We are unsure about the correct shape and pattern as scientists have hundreds and thousands of different ten/eleven dimensional shapes and they just don't know which might be the right one. They strongly believe that knowing the exact shape could completely revolutionize this idea and could even open up paths and answers which we never knew existed.
But if there are extra dimensions then where are they?
Currently scientists believe that those extra dimensions might be in a highly coiled form. There might be tiny curled up dimensions, twined up so small that even though they're all around us but we don't see them. For example consider bacteria on a paper. For the bacteria, the page would be three-dimensional as it would have height, width and length but for us it is only two-dimensional. So it could be true that the dimensions are curled up so small that our naked eyes or even our best microscopes cannot observe them. But in contrast, it might also be true that they are actually too large for us to observe. They might be as big as our observable universe. For example, let's take a cuboid the size of a room and place a bacteria in the middle of the wall. From the bacteria’s perspective it is on a two-dimensional surface but from a third perspective, it's actually a three-dimensional shape. We might be living in a small part of the ten/eleven dimensional shape which is so huge that we comprehend it as only three-dimensional. It could be just like a person locked in an extremely large three-dimensional room. He would say that even the world outside his room is three-dimensional but in reality it could be a ten dimensional world with him embedded in a small part of that world. It's only after we take a fresh perspective to things, we can notice the hidden answers. .
But how does it completely change things?
Currently we have four basic physics laws which are gravity, electromagnetic force and weak and strong nuclear forces. Physicists from all around the world are in a quest to find a single unified theory which explains all those forces and they believe hyperspace is the key to open the door of unified theory. In hyperspace all the laws of physics just fit together like a jigsaw puzzle In our three-dimensional words, we can explain and give reason to almost everything but still we seem to have some scattered and random jigsaw pieces which we just can't fit in to bring out the true image of the universe. Let's say a beautiful crystal shatters and lands on a tabletop and their little insect living on this tabletop. They say let us reassemble the crystal. They work hard pushing those crystals and in the end they are left with two giant crystals. Let's say one of the crystals is quantum mechanics and the other is relativity. They try to bring those chunks of crystals together but no matter which method they apply they just cannot reassemble them. But one day a scientist suggests, let's move one crystal up and then fit it into the third dimensions. This would create a beautiful single crystal. We think this broken crystal is the unified theory and hyperspace is the solution to bring all those shattered pieces together.
We live in a very strange world. The concept of higher dimensions could be nothing less than some science fiction story to some people but it's the questions we ask that makes us different. No one from the 15 century would have believed an individual saying that it is indeed possible to communicate over large distances instantly but now the invention of telephones has completely changed humanity. Maybe the discovery of higher dimensions could be the revolutionary discovery that changes the world!