As far as we know, these all fall into one of just four categories; electromagnetism, gravity, and two kinds of nuclear force.
Physicists from Germany, Switzerland, and Australia have now placed new restrictions on where one example of a ‘fifth’ force may be hiding in the hearts of atoms, exchanging whispers between electrons and neutrons.
And gravity is the most questionable member of the force family, lacking a quantum theory to explain its behavior.
A Yukawa particle is the hypothesized mediator of a possible force within the cores of atoms.
Finding examples where the plot doesn’t match the model could – in theory – indicate a weak additional force operating between neutrons and electrons.
There is a push or pull behind every physics action. These all fit into one of four categories, as far as we can tell: gravity, electromagnetism, and two types of nuclear force.
However, there might be forces that are just too subtle to be readily detected, concealed deep within the tiny storms of particle dynamics.
New limitations have now been imposed by physicists from Australia, Switzerland, and Germany on the potential location of a “fifth” force that whispers between electrons and neutrons inside atoms.
There are obvious holes in our Standard Model of physics that leave physicists perplexed, despite how useful it is at explaining cosmic and quantum phenomena.
For example, dark matter is still a mystery. The reason one type of matter became dominant after the Big Bang is unknown. And since there is no quantum theory to explain gravity’s behavior, it is the most dubious member of the force family.
Expanding the model by adding new fields and particles might greatly aid in the explanation of these enigmatic occurrences.
The proposed mediator of a potential force in atoms’ cores is known as a Yukawa particle. It would subtly affect the interactions between the particles that make up an atom’s nucleus and perhaps with electrons if it were present.
This latest study’s physicists focused on a much smaller area in the orbitals surrounding the nuclei of four distinct types of calcium, in contrast to previous attempts to disentangle the force’s anticipated effects on a cosmic scale.
Because of their attraction to the positively charged particles in the center, electrons are usually confined to their neighborhoods. However, they will briefly visit a higher orbit in what is called an atomic transition if you give them a kick.
The exact timing of this jump is mostly determined by the structure of the nucleus, which means that an element may undergo various atomic transitions based on the number of neutrons it contains.
These differences are mapped into a King plot, which should be fairly easily predicted by the Standard Model. Theoretically, finding instances where the plot deviates from the model might point to a weak extra force between neutrons and electrons.
The researchers measured atomic transitions using five calcium isotopes in two different states of charge, leaving room for a tiny, unidentified force that is controlled by a mediator particle with a mass of between 10 and 10 million electronvolts.
The researchers showed that, despite any ambiguity in their calculations, it was mostly due to a single factor, which may indicate the presence of a fifth force.
To verify whether any dynamics within their resulting deviations were due to the Yukawa interaction or known physics would require more experimentation and better calculations, but at least now researchers know what to look for.
