However, researcher Attila Krasznahorkay and colleagues at the Atomki Nuclear Research Institute in Hungary believe they have found evidence that a fifth force exists in nature. The researchers discovered this evidence in 2015, after observing the light emitted from the decay activity of beryllium-8.
Beryllium-8 is an unstable structural isotope discovered in the 1930s when the first particle accelerator was built in Cambridge. The existence and mode of beryllium-8 decay has fascinated particle physicists.
In 2015, when the proton was shot at the lithium-7 isotope (to create beryllium-8), the Hungarian team discovered that the particle decay result was not the same as the original prediction. They also discovered the appearance of a small 'kick', that is, electrons and positrons - when emitting air during the isotopic decay, in a mysterious way, it shot out of each other to form. an angle of exactly 140 degrees.
Researchers have done many similar tests and all have shown similar results.
Based on that, the team speculated that, at the time of the atom's decay, a new particle was created thanks to the excess energy contained in the atomic components but immediately decayed into a pair. positrons and electrons.
The mysterious particle has an estimated mass of 17 megaelectronvolt so it is called X17 by scientists. This particle carries an interactive force at a distance equivalent to the nuclear width of an atom.
Krasznahorkay said that when they performed the new research with stable helium atoms, they also had the same measurements, the difference here is that the positron and electron pairs burst from the helium atom forming an angle of nearly 115 degrees .
Researchers are continuing to conduct other studies related to X17 particles. If the existence of X17 is confirmed, a fifth force will appear and physics will have to rotate the four known fundamental forces.