At a recent TED talk in Geneva, CERN particle physicist Harry Cliff presented his audience with a controversial new concept: science may be entering an era where "we could be facing questions that we cannot answer. Not because we don’t have the brains or technology, but because the laws of physics themselves forbid it." Key to Cliff’s concept are two numbers: one concerning the strength of the Higgs Field, as validated in recent years by the production of the Higgs boson, and the other being the force exerted by what physicists call dark energy.
Cliff explains that the fine tuning of these two numbers are key to the very existence of matter in the universe: the Higgs Field imparts mass to all of the particles in the universe; and dark energy, a bit of a more nebulous concept, is explained as an effect of the energy of spacetime itself, causing a repulsive force that is accelerating the expansion of the universe. If the Higgs Field were any stronger or weaker, matter would either have too much mass, or no mass at all, and if dark energy was any stronger, it would tear the universe apart.
However, the numbers that come from the theories that predict how these two phenomena operate are extremely different from what is being observed: according to both the theory of relativity and quantum mechanics, the Higgs Field can either be on or off, but wouldn’t have a value anywhere in between. But the value that is being observed shows that the field is only partially on, at only one-ten thousand trillionths of the strength predicted by classical models. Dark energy fares just as bad, with the force being observed being 10ˆ120 (that’s 10 with 120 zeros after it) times weaker than what science has predicted. It is, in fact, considered the worst prediction ever made in physics.
This presents a problem for physicists: if either of these values were where they should be, as per our current model of physics, then the Higgs field would impart either no mass to the universe’s particles, or an impossible amount of mass, resulting in the inability for matter to form. And if the force from dark energy was also as strong as predicted, it would have ripped the universe apart shortly after the Big Bang.
Cliff explains that the discrepancy between the predictions and the observations could be explained if our universe was just one in a multiverse of universes, but currently there is no way to study such a concept. According to Cliff, science may have to turn to more radical theories, like string theory, to address questions that our current scientific model cannot answer.
"We may be entering a new era in physics. An era where there are weird features in the universe that we cannot explain," says Cliff. "An era where we have hints that we live in a multiverse that lies frustratingly beyond our reach. An era where we will never be able to answer the question why is there something rather than nothing."