It is likely that you have ever wondered why the Universe has only three spatial dimensions. The truth is that the natural tendency for ropes, wires or cables to always end up entangling, can help explain the three-dimensional nature of the universe and how it was formed.
An international team of physicists has developed a theory that explains it: shortly after the appearance of the universe, 13.8 billion years ago, the universe was filled with knots formed by flexible threads of energy called flux tubes that join elementary particles .
“Although the question of why our universe has exactly three (large) spatial dimensions is one of the deepest puzzles in cosmology … actually, it is only occasionally addressed in the scientific literature,” the authors explain.
The fact that static volumes of space have three degrees of freedom, width, depth, and length, seems so fundamental that it is difficult to imagine a Universe otherwise. Truth? Imagine a hypercube in 4D as a real object and we will quickly feel that … our mind is in a mess.
We cannot rule out the possibility that there are other dimensions of space. In fact, models such as string theory accommodate nine or more dimensions; But until we find solid evidence of their existence, it’s 3D that we need to worry about.
Physicists, from the universities of Edinburgh (UK), Dortmund (Germany), Aveiro (Portugal), Chapman and Vanderbilt (USA), borrowed a common element from the Standard Model of particle physics and mixed it with a small basic knot theory (a branch of topology) to produce a novel scenario that can not only explain why three-dimensional structures predominate, but also offers a natural energy source for inflationary growth that most cosmologists believe which took place microseconds after the famous Big Bang.
Key element: the flow tube
This element is the flow tube, which has its roots in James Clerk Maxwell’s modeling of electromagnetism in the 19th century. The flow tube is made up of quarks, elementary particles that form protons and neutrons, which are joined together by other adhesive particles called gluons. Hence flux tubes can also be used on a quantum scale to explain why specific types of particles called quarks stick together to give us thick subatomic particles like protons and neutrons. As the bound particles separate, the flow tube extends until it reaches a point where it breaks. The energy in that field results in the production of another quark and an antiquark.
“We took the well-known flux tube phenomenon and raised it to a higher energy level,” explains Thomas Kephart of Vanderbilt University.
If we review current theories, at the time the universe was created, it was first filled with a superheated, electrically charged liquid called a quark-gluon plasma. The scientists observed that an energy version of the quark-gluon plasma would have been an ideal setting for the formation of flux tubes in the early universe: all that immeasurable number of pairs of quarks and antiquarks that were created and eliminated spontaneously, would generate large amounts of flow tubes.
Although the flux tube that joins a quark and an antiquark disappears at this moment of contact and annihilation, there are exceptions. If a tube takes the shape of a knot, for example, it becomes stable and can survive the particles that created it, they would end up forming stable flow tubes when two or more flow tubes become entangled.
This would explain, according to the authors, that the entire universe had been filled with a narrow network of flow tubes . After calculating how much energy this network could hold, they discovered that it was powerful enough to fuel an early period of cosmic inflation.
“Our network of flow tubes not only provides the energy needed to control inflation, but also explains why it stopped so abruptly. As the Universe began to expand, the network of flow tubes began to disintegrate and eventually fell apart. it broke, eliminating the energy source that was fueling the expansion, “says Kephart.
Reference: Knotty inflation and the dimensionality of spacetime. arXiv. arxiv.org/abs/1508.01458 / Knotty inflation and the dimensionality of spacetime Berera, A., Buniy, RV, Kephart, TW et al. . The European Physical Journal 2017 doi.org/10.1140/epjc/s10052-017-5253-3
