In the previous blog, we described the hierarchy of the building blocks of matter. A substance (water for example) is made up of molecules. One molecule of water is made up of three atoms: two hydrogen atoms and one oxygen atom. The atoms themselves are made up of even smaller parts. Whether it’s a hydrogen or oxygen (or any other atom for that matter) atom, the constituent of an atom is a nucleus and a cloud of electrons surrounding the nucleus. The nucleus is a cluster of protons and neutrons. And inside the protons and neutrons we find the elementary particles called quarks. So far, we haven’t been able to peek inside the quark to see what it is made up of. Similarly for the electron, we haven’t yet found out what is inside it. For this reason, we call the electron and the quark the elementary particles. These extremely tiny particles are the fundamental constituents of matter as we know it.
There are six different kinds of quarks and there are five other tiny particles similar to the electron. But broadly speaking, there are two types of particles (quarks and electrons) that make up matter. If you imagine putting a puzzle together then these particles are the pieces of the puzzle. How they fit together is a different thing. There are other particles called bosons which tell us exactly that; that is, how the quarks and electrons interact and fit together to make atoms. There are five types of bosons and their role is to carry the forces that cause the particles to interact. Perhaps the most commonly known one is the photon, the particle of light. Strictly speaking, it’s the particle of electromagnetic energy of which light is a component. X-ray, UV and infrared are also components of the electromagnetic energy. The photons, therefore, carry electromagnetic force and dictates how charged particles will interact. Charged particles are particles that carry an electric charge. The electron carries a negative charge and it is the flow of electrons in conductors (like copper) that is manifested as electricity. The proton is a positively charged particle. As such, the interaction between protons and electrons is governed by photons.
Lesser-known bosons are the W and Z bosons that mediate the weak forces between certain types of particles. The fourth one is the gluon that carries the strong force and is what binds the quarks together to form protons and neutrons. And finally, the fifth boson is none other than the famous Higgs boson.
Why has it suddenly come into the limelight? What is so special about it that makes it so popular? Its proposed existence is not new to science. Almost fifty years ago, a team of physicists, including Peter Higgs, postulated the existence of this elusive particle in order to explain why matter has mass. Think of it this way: a body gathers warmth when placed in a hot medium. Just like in the cold winter days, we gather near the radiators or the fireplace to absorb some of that heat and be warmer. Similarly, by placing matter (i.e. the elementary particles) in a given medium (the Higgs field) then matter gains mass. Why should a proton have the mass that it has? Why should all matter have the mass that they have? Well, it’s down to this Higgs field and the mysterious Higgs boson. I say mysterious but it’s no mystery to science; it’s just that it hasn’t been found yet. Only signs of it are there but not it’s actual presence. It’s like looking at a mysterious shadow on a wall and inferring that someone is lurking behind us. All we need to do now is catch that boson!
So the Higgs boson is here to set the mass of every fundamental particle to the value that allows them to interact the way they do. Had their masses been different or had they been massless, the interactions of these particles would be different, their dynamics different, physics as we know it would be different and life, the universe and everything else would be different. It is of paramount importance, therefore, to finally capture the Higgs boson and prove its existence so that we can show that the theory which postulates its existence, and therefore the characteristics of the fundamental particles, is not just a neat piece of mathematical gimmickry but that it underpins our very existence.
Decades and billions of dollars have been spent on the hunt of this peculiar particle. Yet the game is not over. Teams of scientists working at CERN (Conseil Européen pour la Recherche Nucléaire) dedicate their careers on this astounding project with the hope that one day, most likely this year, the Higgs will finally show its face. And if it does then glory be to physics and our understanding of the universe.
On the other hand, if the Higgs boson doesn’t exist and remains a mathematical fabrication then may this unlock another door and lead us to tackle another confounding conundrum and push the boundaries of physics even further. For it is the very essence of science that the search for new ideas and the expansion of our knowledge and the understanding of our universe is an on-going quest. The hunt never ends…