Scientists have been studying this notion since 1960s, and one of the things they learned is that for the theory to employ, there have to be more dimensions than the four we know of. This concept is not as insane as it sounds, but rather possible.
In string theory, small rings of vibrating stringiness show as various particles via their vibration, such as electrons, neutrinos, and so on, and nature’s force haulers like photons, gravitons, and gluons. Each string is so small that, for us, looks like a particle the size of a point, but each of these strings is able to vibrate with various modes.
Each vibration mode is believed to connect to a separate type of particle; therefore, all the strings vibrating one way appear as electrons, the strings vibrating on another manner looks like photons and so on. What we perceive as particle clashing are, in the string theory view, a set of strings connecting and splitting apart.
However, for this notion to work, there have to be more than four dimensions in the Universe. This is due to the fact that the space-time doesn’t provide the strings with sufficient space to vibrate in all the manners they need to in order to entirely convey as all the types of particles in the world. Simply put, the strings vibrate hyperdimensionally.
Known versions of string theory ask for at least ten dimensions, while another variant known as the M-theory requires 11.
However, how can the string theory’s demand for other dimensions can be merged with our daily experiences in the Universe?
A Fifth Dimension
Fortunately, experts were able to indicate to a historical predecessor for this notion. In 1919, after Albert Einstein revealed his theory of general relativity, the mathematician and physicist Theodor Kaluza discovered something interesting when he added a fifth dimension to the equations he was studying: nothing happened. The number of dimensions has to be added in order to make the theory work in our Universe.
However, when Kaluza made the fifth dimension wrap around itself in what it is now known as the ‘cylinder condition,’ he recovered the regular equations of general relativity in the four known dimensions and got a new equation that mirrored the expressions of electromagnetism. What Kaluza discovered suggested that by adding dimensions, physics could ultimately be unified.
Further discoveries indicated that the additional six spatial dimensions required in the theory have to be wrapped up in a specific bunch of configurations, known as Calabi-Yao manifolds. However, there is no one unique manifold that is enabled by the hypothesis, but around 10^200,000. It appears that when you need six dimensions to wrap on themselves and provide them with infinite ways of doing it, it adds up.
Each possible way impacts the ways the strings inside them wobble, and because the ways that string vibrates decide how they act in the macroscopic field, each possibility of manifold conducts to a particular Universe with its own set of physics.
However, string theory is not done, as there are only different approximation techniques that scientists hope to lead to the real thing. There is, therefore, no mathematical technology that helps following the line, from the particular manifold to specific string vibration to the physics of our Universe.