Everything in this world is made up of matter that is bound together by natural forces. Most of these forces follow a very typical pattern that is outlined in the Standard Model of physics.
However, recent experiments involving electrons and their larger counterparts may be cause for adjusting this model. In theory, electrons, muons, and tau leptons should all share a similar behavior despite their different sizes. This is due to the fact that they all have the same type of charge.
Based on several recent observations, it is clear that there is some unknown force causing the particles to behave differently. In addition, this force interacts differently with each of the three particle types.
Scientists have known for many years that the standard model was not able to account for certain forces like dark matter and gravity. Unfortunately, the majority of large scale experiments did not produce any results that proved the existence of these forces and the standard model was upheld.
However, there have been many new signs of particle misbehavior since 2012 that pertain to a little-explored area of the Standard Model known as lepton universality. In short, this area of the model stipulates that particles like electrons and its larger cousins should behave in much the same way with the exception of variances due to their different masses.
The first surprise relating to this area occurred in 2012 during the BaBar experiment. In this experiment, the concentration of Tau particles was much higher than it should have been. Nothing in the current model explains why the concentration numbers were so off.
Two other experiments since then have had similar results where the concentrations of particles left over after high-speed collisions did not add up based on the Standard Model.
While the results are still being reviewed, it is clear that there is more to these particle interactions than the Standard Model can currently explain. With further research, these findings may open up new pathways for research in the future.