The fifth dimension is a topic that has been abundantly explored in science fiction by many books, series, and movies. And it should not be a coincidence, the eternal search for meaning is intrinsic to human beings. The idea of finding an unknown dimension is a chimera between the scientific and the philosophical, which invites us to get lost in the abstract puzzle of the questions: who are we? And what are we doing here?
A group of scientists from the University of Granada (Spain) and Johannes Gutenberg University (Germany) have found what could be the entrance to the fifth dimension. In reality, it was a fate, since originally the experts were investigating dark matter and thanks to this, they found a particle that could act as a portal to the fifth dimension.
The fourth dimension is time-space
For years, since the 1920s and in an attempt to unify the forces of gravity and electromagnetism, Theodor Kaluza and Oskar Klein speculated about the existence of an extra dimension to those perceptible to our eyes.

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From our perspective, the reality is built on three spatial dimensions (up-down, left-right, front-back). However, Kaluza and Klein added a new dimension to the theory that results in the fourth dimension: time-space.

Scientists discover the possible entrance to the fifth dimension
But scientists never have enough and speculate that there could be an extra dimension, although extremely tiny that would not be perceptible to our eyes at all. Almost eighty years later, our understanding of reality took another unexpected turn. In the late 1990s, researchers came to the conclusion that an added dimension, that is, a fifth dimension, could resolve some of the most tangled questions in particle physics. However, the investigations did not shed light on the entry into a fifth dimension. Until now, researchers from Germany and Spain found a possible way out of the labyrinth.

The great mystery of the fifth dimension
The research published in The European Physical Journal C goes beyond the Standard Model of particle physics. They discovered a theory that predicts the existence of an unknown particle that would be the entrance to the fifth dimension, very similar to the Higgs Boson. The hypothetical particle would surprisingly resolve the question about the abundant dark matter in the Universe.

The particle’s existence necessarily requires the mediation of a new force between elementary particles (the visible universe) and the intriguing dark matter (the dark universe), which sheds light on some open unknowns. “This particle could play a fundamental role in generating masses of all the particles sensitive to this extra dimension, and at the same time be the only relevant window to a possible dark sector responsible for the existence of dark matter, which would solve a problem.
“It only hits two of the biggest problems of these theories, a priori disconnected,” explains Adrián Carmona, co-author of the research.
Despite the encouraging nature of the new theory, there is still a long way to go. Like the discovery of the Higgs Boson, the new hypothetical particle would have to be searched to prove its existence. The central problem is that the particle’s mass is so heavy that not even CERN’s Hadron Collider can produce it. To check the entrance to the fifth dimension, we will have to wait for the new generation of colliders.
This story was originally written in Spanish in Ecoosfera
