A more accurate theory of everything
From our very first science lessons in school, we are told that the world around is made out of building blocks called atoms. Atoms are infinitesimally small, atoms are indivisible and atoms make up all matter in existence, everything from a banana to a human. Depending on how far you took your studies, you might know that all or part of these statements are wrong.
You learn that they are all in fact simplifications of reality but you still probably think that the general premise is true. I’m afraid it isn’t. The world isn’t really made up of atoms.
I would love to share with you a more realistic picture of nature and reality.
The most cogent theories in physics today reveal that the fundamental building blocks of nature are in fact much more abstract and esoteric than particles. These entities are fluid-like fields which are spread throughout the entire universe. Said fields take particular values at every point in space, values can change through time.
It was in fact a 19th-century scientist called Michael Faraday who brought the idea of fields to prominence. He theorised that invisible electric and magnetic fields permeated through all of space. Faraday’s genius lay in his ability to recognise that something existed despite the fact that it could not be seen.
Unfortunately, it took over 150 years from the times of Michael Faraday for the scientific community to truly recognise and appreciate how important these fields were. A revolution took place during these years and quantum mechanics was born, with Schrodinger and Heisenberg (among others) beginning to understand the complexity of the world on an ultra-small level.
Now, the fun begins at the intersection of quantum mechanics and Faraday’s idea of fields. The fact these two areas share any overlap may come as a surprise since the quantum world deals with discrete values (“quantum” meaning lump of energy) whereas fields are continuous by nature.
This intersection is known as quantum field theory (QTF).
As I explored briefly in my previous post, this theory states that particles are simply “ripples” in different fluid-like fields which fill the entire universe. To me, it is remarkable that an idea so fundamental to understanding the true nature of our universe was proposed over 150 years ago.
The fact that these fields are omnipresent means that even empty space, known as a vacuum, is not empty. Below is a 3D representation of what empty space looks like, according to a computer simulation based on the Standard model.
Source: An animation by Derek Leinweber, an Australian professor of physics, created through the use of supercomputer simulations (c.2004)
This erratic model looks the way it does due to the Heisenberg uncertainty principle, which means that the energy states of each of these fields cannot rest at 0. Due to this, what are known quantum vacuum fluctuations occur and it is these that you see above.
Understanding from first principles the nature of these quantum fluctuations is by no means simple. In fact, it is one of the infamous millennium problems, problems which can earn you $1 million by solving.
It is astounding that understanding “nothing” is so immensely difficult and shows how much more difficult it is to understand the true nature of our universe on a larger scale.
So how many of these fields exist in our universe? Thousands, right? Maybe millions or an infinite number? Wrong. Only 17
These include what is known as the first generation of particles – of, should one say fields – which are the electron, up quark, down quark and neutrino. The electron, as I am sure many of you know, orbits around nucleons (protons and neutrons) and the quarks make up the nucleons themselves. The last of these, the neutrino, is notably smaller than any other elementary particle and only interacts with the weak nuclear and gravitational forces.
Where do the other particles (fields) come from? Turns out the universe, for whatever reason, decided to replicate this first generation 3 times over. In other words, there are two more types of electron, quark and neutrino respectively. (See an earlier post I wrote about the Standard Model to learn more about these elementary particles).
These 12 fields interact with one another through 4 different forces: gravity, electromagnetism, the strong nuclear force and the weak nuclear force. While many of you may be familiar with the first two of these, the latter two may be less well known. In brief, the strong nuclear force is responsible for holding quarks together within protons and neutrons, and the weak nuclear force gives rise to phenomena such as radioactive decay and nuclear fission.
In a similar way to the 12 elementary particles, these forces (known as the 4 forces of nature) can also be thought of as fields. Faraday kindly developed our understanding of the electromagnetic force as a field. The strong and weak nuclear forces also have fields associated with them, known as the gluon boson field for the strong force, and the W and Z boson fields for the weak force. Einstein brought us the idea that the field associated with gravity is a combination of space and time. Peter Higgs further developed Einstein’s idea by theorising that gravity was the result of interactions with yet another field, the “Higgs field”.
These 12 matter fields and 5 force fields give us the most reductionist understanding of our known universe. To me, the fact that everything I have ever seen, touched or experienced is composed out of the same 17 distinct entities is mind-bogglingly fascinating, almost supernatural.
While these 17 fields can explain the nature of everything on Earth, our universe is slightly more complicated. It consists of mysterious invisible or “dark” matter and even more mysterious “dark” energy, a field in itself. This peculiar field permeates the entire universe and, in simple terms, means that everything repels everything else. Though I hope to learn more about these esoteric aspects of our infinitely complex cosmos, they are currently beyond my understanding.
As you may have noticed, a key inspiration for me to write these entries in the past have been the wonderfully informative lectures given at the Royal Institution. In this particular case, David Tong’s talk about the fundamental building blocks of our universe is what spurred me to explore this topic in more detail. I highly recommend one and all who are curious to watch it here: https://www.youtube.com/watch?v=zNVQfWC_evg&t=2158s.
Beyond Science 