Physicists explain the emergence of an ultra-powerful neutrino with a fifth dimension

In February 2023, the KM3NeT neutrino telescope, under construction off the coast of Sicily, Italy, recorded an ultra-high-energy particle unknown to science. This neutrino was 35 times more powerful than any similar particle previously observed, sparking great interest in the astrophysical community. For three years, scientists considered various theories such as blazars and cosmic ray collisions, but none could fully answer the questions raised. In a new paper published in the journal Physical Review D, a group led by Dieter Lüst of the Max Planck Institute for Physics in Munich hypothesized that this mysterious particle originated from a black hole explosion within a fifth dimension, not another universe. This was reported by Ixbt.com reports that

According to ixbt.com, the subject concerns primordial black holes—hypothetical objects that appeared immediately after the Big Bang in the early universe. According to Stephen Hawking's theory, they gradually evaporate and emit particles. Such a black hole, with the mass of an asteroid, could have survived to this day, and its final flash may have triggered the neutrino flux. A year ago, researchers at the Massachusetts Institute of Technology (MIT) calculated that such an object located 2000 astronomical units from the Sun could cause the impact recorded by KM3NeT. However, the fact that other instruments did not record photons became the main flaw of this version.

Secrets of the surviving hypothetical fifth dimension

To resolve this contradiction, Lüst and his colleagues added the "dark dimension" concept to the ancient theory. According to an idea proposed by Harvard University expert Cumrun Vafa, the fifth dimension is an additional effect of dark energy, existing at every point of spacetime in the form of a micron-sized circle. It is invisible because all interactions, except for gravity, are confined within a four-dimensional brane. If the exploding primordial black hole is located within this dimension, according to physical laws, only neutrinos can escape from it, and photons cannot—which is exactly what was observed in practice.

This model, in turn, refers to black holes formed as a result of the collapse of cosmic strings. The high density around the strings created sufficient conditions for the formation of a black hole. However, skeptical scientists emphasize that the existence of the fifth dimension has not yet been fully proven. Dan Hooper, a cosmologist at the University of Wisconsin-Madison, noted that the researchers' claims are very bold and difficult to defend. Additionally, the much larger IceCube detector at the South Pole has not recorded a single such high-energy neutrino in the last 15 years, raising further questions.

Future research and new telescopes

Scientists believe that upcoming space exploration projects will clarify such puzzles. In particular, the Radio Neutrino Observatory under construction in Greenland will detect neutrinos not through optical flashes, but using radio frequencies. This allows for expanding the distance between stations and covering enormous energies. Also, the second-generation IceCube project plans to deploy a radio antenna network over an area of 500 square kilometers. For now, there are other, more conventional explanations for the impact recorded by KM3NeT, such as cosmic rays or blazars, but since none of them have been fully proven, the hypothesis of black holes in the fifth dimension remains under scientific discussion.