Dark matter, the invisible substance that makes up much of the mass of the universe, can consist of massive particles called gravitons that first came into existence in the first moment after the Big Bang.
These hypothetical particles might be cosmic refugees from other new dimensions, as new theory suggests.
Is Graviton Dark Matter?
The researchers’ calculations have assumed that these particles may have been created in adequate quantities to explain dark matter which being “visible” only through the gravitational pull on ordinary matter.
“At the start of the universe, the collision of massive particles resulted in the formation of huge particles called gravitons. This process is believed to be less evident for gravitons to become candidates for dark matter.
However, in a new study published in the journal Physical Review Letters in February, Cacchapallia, along with Korea University physicists Haying Tsai and Seung J. Lee found that a sufficient amount of gravitons were generated in the early universe to account for all the dark matter we have currently detected in the universe.
This study showed that gravitons, if present, would have a mass less than one megaelectron volt (MeV), or twice the mass of an electron. This mass level is well below the scale at which Higgs particles produce the mass of ordinary matter, which is important for the model to produce enough to account for all the dark matter in the universe.
(For comparison, according to the National Institute of Standards and Technology, the lightest particle known, the neutrino, weighs less than 2 electron volts, while the proton weighs about 940 MeV).
The team discovered these hypothetical gravitons while looking for evidence of additional dimensions that some physicists suspect existed along with observed three-dimensional space and four-dimensional time. When gravity is applied through a further dimension in this theory, it is specified as a huge weight in the universe.
However, these particles will only interact with existing substances and gravity. This explanation is always similar to the dark matter that does not easily interact, but it provides gravitational impact everywhere in the universe.
“As a particle of dark matter, the main advantage of large-scale weight is that gravity can interact, so you can avoid attempts to detect their existence,” Kachcha Pal said.
Other Candidates For Dark Matter
Conversely, other proposed candidates of dark substances such as huge particles, axions and neutrinos, which are weakly interacting, can be felt by subtle interactions with other forces and fields.
A huge weight provides another benefit of barely interacting gravity with other particles and forces in the universe.
“Due to a very weak interaction, they collapse because they remain stable in the lives of the universe,” Cacciapaglia said. today.
Why Can The Gravitons Become A Suitable Candidate For Dark Matter?
In the past, gravitons did not seem to be a candidate for dark matter. Because the process of creating them is extremely rare.
However, the team found that in the picosecond (trillionth of a second) after the Big Bang, more gravitational forces were created than previously thought.
The study found that this increase is sufficient to fully explain the amount of dark matter that a giant graviton detects in the universe. “The improvement was really shocking,” said Cacchapalla. “We had to run a lot of tests to make sure the results were correct, as the results changed the paradigm of how we see massive gravitational particles as potential dark-matter candidates.”
The giant gravitons form below the Higgs particle’s energy scale, there are uncertainties associated with higher energy scales that modern particle physics does not account well for.
What Is Group Theory?
Group theory links the physics studied in particle accelerators such as the Large Hadron Collider with the physics of gravity.
This means that powerful particle accelerators such as CERN’s Future Circular Collider, which will start operating in 2035, could find evidence of these potential dark matter particles.
“Perhaps the best we can have is a high-precision particle Collider of the future,” said Cacciapalla. “This is currently under observation.”