The aim of science is to describe as best as we can the natural world around us. Hypotheses are formulated, tested, and when successful turned into theories. The theories then continue to be tested and challenged. The process doesn't stop. We push them to their limits and sometimes we can go beyond them. And we might be lucky enough to see this very soon.
In the last few months, there have been several indications that the Large Hadron Collider at CERN has seen hints of unexpected phenomena. A new particle has been rumored, and a well-predicted particle decay doesn’t actually behave as expected. While these events have not been proven beyond doubt to be correct, more and more people believe that we are on the edge of discovering a whole new realm of physics.
Modern particle physics is described by a theory called the Standard Model (SM). The SM describes the properties of the fundamental particles, quarks and leptons like electron and neutrinos, as well as describing how they interact according to three of the four fundamental forces, electromagnetism and the strong and weak nuclear forces.
The SM has been the highest point of fundamental physics in the 20th century. Its most famous prediction is the Higgs mechanism, which describes how particles acquire mass. The existence of the Higgs and its boson was confirmed at CERN in 2012.
But for all its power, we have always known that the SM was limited. The SM doesn’t predict why the universe is made of matter instead of antimatter; according to the SM they must have been created in equal amounts from the Big Bang.
Dark energy and dark matter are also absent from the SM, and since they make up 95 percent of the universe, that's a big deal.
Composite 3D image of LHC tunnel and a graphic of what's going on inside. CERN/Daniel Dominguez
The biggest limitation though is that gravity is not included in its formulation. Attempts to include gravity have so far been unsuccessful, and the SM is regarded as incompatible with general relativity, which is the best theory of gravity we have today.
While these gaps hint at a hidden better theory, we are yet to find evidence of it. So far no experiment has definitely contradicted the SM to a "five sigma" level. This is the golden standard of physics, and it means that we are yet to see a contradiction proven to 99.99994 percent.
For years, scientists have been trying to find one or more smoking guns, and now CERN seems awfully close to finding a proven contradiction. This doesn’t mean that the SM will be thrown out of the window. Just like many theories before it, it will be a limited scenario of a wider new theory.
CERN is now ready to start the 2016 physics run after its annual winter break and, barring more weasel incidents, it aims to produce around six times more data than in 2015, delivering more information about the Higgs and other phenomena in fundamental physics.
"What we are looking for are very rare phenomena, (and) when you are looking for very rare phenomena you need a very large number of collisions," Frederick Bordry, CERN director for accelerators and technology, told AFP.
"We are really at an energy level that enables discoveries. If we have nature on our side, I think we will discover new particles and open a new road for physics beyond the Standard Model.”
This is a very exciting time for fundamental physics. It’s like knowing that Einstein is about to publish his work. We don’t know exactly what this new physics is going to look like, but we can’t wait to find out.