Perhaps the most important physics discovery of my lifetime has finally been announced. I say 'finally' as its existence has been predicted by the 'Standard Model' for a long time and I have already mentioned this possibility/probability in an earlier article on this website (link).
Its confirmation is important to everyone, not just to physicists working in the field of quantum mechanics. Like the confirmation of the predictions of Einstein's Theory of Relativity we are now confronted with a new model of reality that has moved beyond an esoteric theory to the understanding that this is how the Universe actually is; at least as far as the Standard Model goes.
When I was at school, fifty-something years ago, our teacher began the first physics lesson by hitting the desk with his hand. 'That hurt!' he said, holding up a reddened hand, 'but you might be surprised to know that I did not actually touch the desk!' Of course he had, if we accept the conventional meaning of the word 'touch' but the point he was making was that atoms of which our physical world is constructed do not touch each other. They are largely ephemeral; apparently just empty space.
At that time atoms themselves were theoretical. No one had seen one. Their existence and properties were inferred. In high school we were invited to think of atoms as little solar systems with a sun at the centre consisting of a clump of protons and neutrons circled at a huge distance by planetary electrons. Chemists still tend to think of them like this.
Physics was still largely theoretical. Radios, TV and computers used vacuum tubes. The first practical semiconductors, transistors, were discrete and the size of a pea; microchips had not been invented. Electron tunnelling and lasers were esoteric theories; light emitting diodes (LEDs) and semiconductor memory devices had not been invented. Fibre communications and desktop computing and were many years in the future.
Later on at University we discovered that electron orbits were not necessarily circular or elliptical but conformed to wave functions and energy levels; still later that neutrons and protons were shorthand for more complex entities nominally having 'flavours' of 'spin', 'charm' and 'topness'; together with 'strangeness' and 'colour'. These words were chosen to represent hypothetical qualities in a theoretical model; not our conventional understanding of the words; much as we use the letters A-F as numbers in hexadecimal notation (base 16) in computer code.
Reality had started to get truly weird. Two underlying, still hypothetical, classes of entities were named 'fermions' after Fermilab in Illinois, in turn named after the physicist Enrico Fermi, containing the sub-set of 'quarks' (the original class of particles identified by the 'atom smashers') named after the seagulls' cry in James Joyce's Finnegans Wake; and 'bosons' named after the Indian physicist Satyendranath Bose. In this hypothetical model fermions are the building block of atoms. Both protons and neutrons consist of three quarks (two up and one down and vice versa); electrons are also fermions. The interactions of fermions are mediated by the exchange of bosons; for example, photons.
The fermions and bosons of which atoms are constructed, and by which they interact, bear no relationship to our everyday experience of matter; and to call them 'particles' can be very misleading. In addition to behaving like discrete objects (quanta) they also have the properties of waves and can be physically split, in conventional three dimensional space, but somehow remain a single entity (a quantum pair). Very weird! But we already use this property in practical devices.
Today we can move individual atoms around as we might shuffle a bag of marbles. Even biologists work at the molecular level. This too is very weird because, as we have long realised, atoms are not 'solid' objects in the sense we are familiar with.
Our physical world, the objects that give rise to our everyday perceptions, like people, trees and tables, seems to be made of solids, liquids and gas. They seem to be hot or cold to have colour and texture and to persist through time. But we now know these appearances to be due to an underlying structure of the Universe that defies our everyday experience.
Proof of this 'weird' reality can be found in every mobile phone shop. If electromagnetic theory did not effectively describe how the universe really is phones would not communicate; if relativity was terribly wrong the GPS navigation would not locate you correctly; if quantum theory was nonsense the microelectronic circuits and the display would not work.
Theorists have been able to construct several models that are consistent with what we know about this underlying reality. The most useful one, the one that allows us to build a mobile phone, is called the Standard Model. But this model needed one key boson (that god-dammed missing particle) to be found to verify its basic premise; or it needed to be thrown out - and to start again. The biggest physics experiment ever built; the Large Hadron Collider at CERN in Switzerland set about the search. Now like a 'needle in a haystack' it has been found.
So what! You say.
So my teacher was right; our world is not really as it appears to everyday experience. It is far, far more interesting!
Now physicists, astronomers, and other researchers have an important part of the puzzle and can start to fill in the rest. For example, it now seems probable that there are more than the three apparent space dimensions; height, width and depth. We humans are just not equipped with the sensory apparatus to perceive this directly.
Today as a result of our sophisticated understanding of the 'reality that lies behind the appearances' we can make things once only possible in science fiction; like light without heat; or our phones. Who knows what we may be able to do in another fifty years?
But there are profound implications for philosophy too. This week the world took another step in human understanding.
For a really easy to understand explanation of the Higgs boson follow this link.
For a longer discussion of the philosophical implications go to the Meaning of Life by following this link.
For a short, but less easy, explanation of the Standard Model follow this link.