I spend a fair amount of time giving public lectures on particle physics and cosmology around the world. Quite often, I receive the same question from the audience, “what is this good for?”
There is a wonderful movie titled Particle Fever, a documentary about the discovery of the Higgs boson at the Large Hadron Collider (LHC) at CERN filmed over five years. It describes the excitements, disappointments, challenges, and the human emotions experienced by the scientists. I highly recommend this movie, which is available on iTunes and Netflix. Lyn Evans, who led the construction of the LHC and is the Director of Linear Collider Collaboration, appears many times in the movie.
About twenty minutes into the movie, David E. Kaplan, the producer of the movie and one of my collaborators, is shown answering precisely this question what the research in particle physics is good for. He answers simply, “I have no idea,” and the audience bursts into laughter. And David continues. “We have no idea. When radio waves were discovered, they weren’t called radio waves because there were no radios. They were discovered as some sort of radiation. Basic science for big breakthroughs needs to occur at the level where you are not asking what is the economic gain. You are asking what do we not know, and where can we make progress. So, what is the LHC good for? It could be nothing, other than just understanding everything.”
We humans are curious creatures, always trying to make sense of the world around us. This curiosity propelled us from apes to an intelligent life form, capable of manipulating the environment rather than being subject to it. It has its downside, namely that we create havoc to the environment to the extent that we are now changing the climate of the entire planet we live on. Yet it is undeniable that our curiosity allowed us to improve our quality of life. We changed ourselves from hunters-gatherers to members of modern civilisation. We don’t worry about getting eaten by predators; we worry whether we have enough savings after retirement.
Indeed, basic science aims at making sense of everything. We want to know why we age and die. We want to know how we evolved into different races, ethnicities, cultures, and languages. We want to know how life was born on this planet, or possibly on other planets. We want to know how our solar system was made. We want to know how we came to be.
How did we come to be? Modern science, in particular particle physics, astrophysics, and cosmology, revealed a stunning story. Much of our bodies were synthesised in stars that exploded billions of years ago. The stars were formed by the gravitational pull of elusive dark matter, a mysterious matter that dominates the Universe yet none of us managed to meet so far. Atoms in our bodies would vaporise in nanoseconds if there weren’t for the Higgs boson that is frozen everywhere in space. We live on the sacrifice of a billion friends that annihilated together with dangerous anti-matter; we still don’t know how a billionth of matter could survive. And the whole thing started from quantum fluctuations, lending and renting tiny amounts of energy due to the uncertainty principle, when the whole Universe we see today was much much smaller than the size of an atomic nucleus.
Why do we care about these questions? I don’t know. But we do. People were burned and arrested when we realised that we are not at the centre of the Universe, but rather circled around the Sun. Now we know the Sun is not the centre of the Universe either, and circles around the centre of galaxy every 200 million years. And our galaxy is only one of a hundred billion galaxies in the Universe we can see. Moreover, what makes up the galaxies is not atoms we are made of, but mostly rather the mysterious dark matter.
Actually, the modern civilisation was built pursing these seemingly useless questions. We can fire canons and missiles, and launch artificial satellites because we managed to understand how planets and stars move. We can call friends in different countries because we managed to understand what light is. We can carry smart phones in our pockets because we managed to understand what tiny electrons do in semiconductors. We can build maglevs much faster than Shinkansen in Japan because we were curious to study what happens to metal when it is cooled to very low temperatures. We developed magnets to keep the protons running at 99.999999 percent of the speed of light inside the circular tunnel, which led to medical imaging to spot where cancer cells are. And we can buy books and clothing from our living room because of the web invented at CERN for scientists to exchange data for this kind of pursuit.
There is a famous episode about Michael Faraday, when he was trying to understand how electricity and magnetism work. When William Gladstone, then British Chancellor of the Exchequer (minister of finance) asked of the practical value of electricity, Faraday responded, “One day sir, you may tax it.” I seriously doubt Faraday had any idea what role electricity plays in modern civilisation, but he was absolutely correct. We live and tax on power.
There are probably two reasons why basic science pushed the humankind forward. One is that the acquired knowledge from curiosity itself is crucial to advance technology. The other is that the tools needed to acquire knowledge drive fundamentally new technology. Either way, the pure curiosity has been the driver for more and more sophisticated technologies, which help our daily lives to make things possible that used to be unthinkable.
Projects like LHC and International Linear Collider (ILC) belong to the second category. They require such demanding technology, they inevitably lead to technological breakthroughs. Even though it is difficult to foresee, just like what David said, building ILC would lead to new breakthroughs and innovations, which in turn will help our society in some big way.