A few months ago the Center for European Nuclear Research (which goes by the acronym CERN) reported it had found evidence of the most-wanted subatomic particle – the Higgs Boson (aka the God particle). If this finding is confirmed it will wrap up one of the longest-standing loose ends in our current model (the Standard Model) of particle physics. In fact, the Large Hadron Collider was constructed at CERN pretty much specifically to look for the Higgs particle – one of the most expensive scientific instruments ever built. So it is understandable to wonder what it is about the Higgs that warrants such effort and expense – and whether or not it’s worth it. One place to start is with what the Higgs particle is and why we even care about it.
One of the biggest questions in physics is why anything has mass at all, and why things have the mass that they do. Photons, for example, are massless, protons have a mass of a tad more than one atomic mass unit, and electrons are about one-two-thousandth the mass of a proton. When you add up the masses of all of the protons (and electrons and neutrons) in our bodies you get the mass of a person. But what isn’t explained by the Standard Model is why a proton weighs one amu and not half (or double) that amount. This is where the Higgs comes in.
In 1964 Scottish physicist Peter Higgs proposed that a particle with some very specific properties could account for this. Specifically, Higgs proposed that the Higgs particle (and its accompanying field) permeates the universe and it interacts with all of the other particles in creation. Think of trying to pull a piece of plywood through water – it can cut through the water edgewise with very little resistance or it can be pulled through broadside at great effort. Edgewise the plywood hardly interacts with the water at all – the equivalent of a particle like the electron that barely interacts with the Higgs field and that has little to no mass. That’s the theory anyhow, but until the Higgs can be found, identified, and studied we don’t know if the universe matches up with the theory.
OK, so in the next few years we might know a little more about how the universe works, but is it really worth a decade’s work and $9 billion just to figure this out, especially when there are poor and hungry people in the world and in times with so many financial and economic problems? Is it really worth it or is the Higgs particle and all of the other abstract knowledge just a luxury that we cannot afford?
The problem with abstract knowledge is that we never know when it will become useful. The galvanic effect was discovered in the late 18th century and it led to the invention of batteries, but there was nothing for the batteries to power for more than a century – twitching frog legs and stored electrical charge were good for laboratory demonstrations and not much else for decades. For that matter, electricity was named by the Ancient Greeks but it, too, was not put to any real use for a few millennia. When the laser was first developed it was called “a solution in search of a problem” – it was an answer to a decades-old speculation and little more. These one-time curiosities are today part of our scientific and intellectual infrastructure – part of the foundation upon which much of our technology and our society rest. And had the scientists who made these discoveries – and so many others – been dissuaded by thoughts that their work might never be used to make the world a better place, had they been dissuaded by thoughts of cost-benefit analysis or the lack of immediate return on their investment of time and money then we might not today have the technology and the standard of living it has brought with it. And it is safe to say that those who discovered electricity, batteries, the electron, and lasers never conceived of the technology that their discoveries would one day unlock.
So one way to look at the CERN accelerators and the particles they will find is as a form of intellectual insurance policy – an investment in our intellectual future that might someday help to spark whatever the next level of technology and discoveries there might be. This sounds good with regards to physics research as well as biology and chemistry and some of the other sciences that we know can give rise to practical applications. But is this the only reason to try to understand the universe, or does knowledge have an intrinsic value in and of itself?
This is a question that I cannot pretend to be objective about – I have been a scientist for a number of years and I firmly believe that the pursuit of knowledge for its own sake is an important endeavor. If we look at the history of humanity we see a constant curiosity and a continual search for knowledge – this curiosity is part of what led us to explore and populate the Earth and is what keeps us pushing to explore and learn what we can about the world and the universe around us. Part of what defines us as a species is our continual quest to learn what’s on the other side of a mountain range or beyond the horizon – as we have explored our planet and filled in the blank spots on the maps we have been increasing sublimating our innate curiosity by extending our quest into realms that our bodies can’t enter – the depths of the universe and the infinitesimally small reaches opened up by our experiments in high-energy physics.
This exploration has often been expensive and the cost keeps increasing. In the realm of physics, we can detect alpha particles, electrons, and neutrons in nature and need only buy (or make) the instruments to detect them – this level of physics can be accessed for only a few thousand dollars. Identifying protons and doing the next level of physics requires more – for millions of dollars we can produce artificial radionuclides and can split (or fuse) atoms. But to go further – to produce (and identify) the subatomic particles that help us to really start to understand how the universe is put together takes devices that cost hundreds of millions or even billions of dollars. On the other hand, the cost of expanding our physical horizons is high as well – space probes, huge telescopes, and manned space travel are about as expensive as high-energy physics. The question is what is more expensive – basic research that may have no utility, or deciding to learn no more. The Higgs boson – and whatever comes next – may or may not one day turn out to have a use. But we know that nothing will ever come of failing to look.