The ancient Greeks were a cleaver bunch, for example they had a simplified version of the periodic table. That is they believed that everything is made up of combinations of 4 elements, earth, air, fire and water. We may ridicule this idea of the 5th century BCE now, but it isn’t too far from what we believe in our so called “enlightened” age. Everything is made up of combinations of elements, not 4 elements i, but 118 elements all found on the periodic table. Only 118 why? As atoms become larger the number of protons increases, protons repulse each other and the forces in the atom then find it difficult to hold the nuclei together, this is one reason large elements tend to be radioactive. In particle acceleratorsii we can push the limits of what is possible and collide smaller elements together to make bigger elements unknown on the earth. Thier is a theoretical maximum size of an atom, so the periodic table cannot be extended forever ( according to the Bohr model of the atom 137 protons is the theoretical max size of an atom, as according to this model first shell electrons would need to go faster than the speed of light if they had more than 137 protons, clearly not possible. The quantum mechanical model though theorizes 172 as the maximum nos of protons, so let's just take this as the theoretical maximum size)iii The periodic table can be used to explain the physical and chemical properties of the elements and materials that make up everything. Much can be said about this topic, but we won't, this can wait for a future blog. The periodic table is an elegant organized thing, the culmination of hundreds of years of science, from the Greeks in the 5th century BCE to Mendeleev in 1869iv. Now we can go further we can see right into the atom, beyond protons, neutrons and electrons. It's a bit like comparing a black and white aerial photograph of a city taken in the 40‘s and comparing it to a supersensitive satellite image. Not only are main junctions and roads seen by satellite images but so is the half-eaten discarded kebab. With the so called standard model of particle physics, the most precise model of particles and their interactionsv we can now investigate the kebab so to speak not just the main junctions as described by the periodic table. So let's do this.
Peering into an atom we have electrons, protons, and neutrons. However, in the 60’s quarks were theorized, that is particles that make up neutrons and protons, from 1967 to 1973 this was then confirmed experimentallyvi. Particle accelerators have now discovered that atoms are made up of 3 particles, electrons, the up quark and the down quark. Protons and neutrons are made up of a set of three quarks. Neutrinos don’t make up atoms but billions of them fly through us every second. This is known as the first generation of particles. Two other generations of particles exist, each a set of four particles equivalent to the first generation of particles except they are heavier. All these recently discovered particles are known as fermions. Then there are particles known as bosons, these force carriers give rise to electromagnetism, the strong force, and the weak force. Physicists are still hunting for the particle associated with gravityvii. Gluons are force carriers that glue quarks together into protons and neutrons, the so called strong forceviii. Photons carry the electromagnetic force (the force between charged particles), the discovery of photons kick started the field of quantum mechanicsix. This brings us on to the Z and W+,W- bosons. These particles are responsible for the weak force, a force which causes things to fall apart. For example, these particles are responsible for beta negative decay where a neutron is transformed into a proton, electron and an antineutrino, beta positive decay a proton being transformed into a neutron, a positron and a neutrino. Anti matter such as antineutrinos exists in very small quantities, thankfully as matter and anti-matter anhilate each otherx. Then this brings us on to Peter Higgs, who won the nobel prize for theorizing the Higgs bosson a particle responsible for giving matter massxi. An often-used illustration which tries to explain how force carriers work is shown below, the exchange of a ball between 2 people standing on seperate boats, causing both people to move (conservation of momentum application), likewise the exchange of a bosson will effect the donor and the acceptor. There we have it a quick glance at the half-eaten kebab. The standard model of elementary particles is also summarized in a diagram below.
Physics and chemistry can explain much about matter but where did these particles come from in the first place, its clearly nonsense to say something comes from nothing, particles do appear and disappear in empty space, but empty space is not the abscence of anything. One thing is for sure after the big bang we did have something and we are all beneficiaries of it. What will be discovered next, who knows, the particle associated with dark matter perhaps?
"My own view is that the discovery of the Higgs boson is really just the tip of the iceberg."
Peter Higgs
All this is pretty mind-blowing stuff.
i https://www.sciencenews.org/blog/context/greek-philosopher-had-right-idea-just-too-few-elements
ii https://www.wired.com/2016/01/smashing-new-elements-into-existence-gets-a-lot-harder-fromhere/#:~:text=But%20the%20best%20bet%20for,berkelenium%20(atomic%20number%2097).
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