What are we ? ; the ultimate question; we are god’s particles!
What are the essential building blocks that make us and this universe? What determines the size of objects that we see around us or indeed even the size of ourselves? The answer is we are made of and our size is decided by molecules and in turn the atoms that compose these molecules.
But what are these atoms made of and what determines the size of the atoms themselves? Quantum theory and atomic physics provide an answer. The atom is almost fully an empty space with a nucleus in the middle .The size of the atom is determined by the orbits of the electrons orbiting the nucleus. If a whole football stadium is an atom, then the nucleus’s size can be compared to a fly sitting in middle of the football field. The nucleus in turn is made of protons and neutrons and both of them are in turn made of quarks. Bigger the size of the orbits around the nucleus, bigger will be the size of the atoms. The size of these orbits is determined by the mass &number of the electrons. So, if the electrons were smaller, the orbits (and hence all atoms) would be smaller, and consequently everything we see would be smaller. In short quarks and electrons are the essential building blocks of everything in this universe.
So, the question is where do quarks and electrons get their mass from? Understanding the mass of the electron for instance is essential to understanding the size and dimensions of everything around us. So the essential question is how did electrons & quarks get their mass? It’s proposed that they get their mass when they move through a field called Higgs field which has force particles called Higgs bosons.
So everything that we see around us and everything that we hope to see in future in this universe essentially starts off from an interaction with Higgs bosons. No wonder its called the god particle!
Enter bosons and fermions!
Well, to cut a long story short, physics essentially is a study of various forces that are at work in this universe. The most common force that I and you know is the mechanical force. That’s one we see in action when I push you, when you throw a ball, when an engine runs a car. And naturally most of the early laws of physics were laws of mechanical forces (refer to earlier note about relativity). There are four other forces in action in the universe we inhabit. First is gravity, second is electromagnetism (the force that lights up the computer screen you are reading this from or lights up or the light behind you). Third and fourth types of forces are the strong and weak nuclear forces (the ones that are behind the atom bomb and the energy of the sun)
Now let’s go back to mechanical force once more. Imagine me pushing you with my hand. Now I am the source of the force here and my hand is the medium through which that force acts on you. Simple, right? Now let’s take electromagnetic force, the light behind you. We know that the source of electricity is electrons. It’s true about electromagnetic force also as electricity and magnetism is the same force. So if electrons are source of the force then what’s the medium through which electromagnetic force acts? Electromagnetic waves are the medium. All of us know one type of electromagnetic waves, its our light! Yes, the light we see and make us see.
Maxwell in mid 19 th century unified electricity, magnetism and light by making electromagnetism a single force which acts through light waves (electromagnetic waves). Quantum mechanics evolved in 20th century and with its evolution it became inevitable that there has to be a quantum explanation to all forces in the universe like gravity, electromagnetism, and two new forces described in 20th century, the strong and weak nuclear forces. The quantum explanation for all these forces are that they are transmitted by various elementary force carrying particles called bosons. These force carrying particles fly back and forth between matter particles transmitting these forces. These matter particles (we know and feel them as mass) are called fermions (The distinction between particle and wave has disappeared in quantum theory.)
In the 1960s, Richard Feynman described quantum electrodynamics, or QED, a quantum mechanics explanation of electromagnetism. In it, electrons were the fermions and photons were the bosons..
After Maxwell, now weak nuclear and electromagnetic forces unites; with a new dilemma!
The "weak nuclear" forces, involved in radioactivity and in the Sun's power generation, are in many ways very similar to electromagnetic forces, save for being much weaker and restricted in range. This is the force that keeps protons and neutrons together in the nucleus. Murray Gell-Man in 70’s found that quarks are the building blocks of protons and neutrons. A unified theory of weak and electromagnetic forces (electro-weak theory) was proposed in 1967 by Steven Weinberg and Abdus Salam . The weak forces are due to the exchange of W and Z particles (bosons) and quarks present in protons and neutrons are the matter particle (fermions). Their short range, and apparent weakness at ordinary ranges, is because, unlike the photon, the W and Z are, by our standards, very massive particles, 100 times heavier than a hydrogen atom. The "electro-weak" theory has been convincingly verified, in particular by the discovery of the W and Z at CERN in 1983, and by many tests of the properties. However, the origin of their masses remains mysterious. Our best guess is the "Higgs mechanism" - but that aspect of the theory remains untested.
The god particle!
Higgs proposed that the whole of space (including vacuum) is permeated by a field, similar in some ways to the electromagnetic field. As particles move through space they travel through this field, and if they interact with it they acquire what appears to be mass. Fields have particles associated with them, the particle for the electromagnetic field being the photon. So there must be a particle associated with the Higg's field, and this is the Higgs boson (god particle). Finding the Higgs boson is thus the key to discovering whether the Higgs field does exist and whether our best hypothesis for the origin of mass is indeed correct.
Well let’s try to simplify this with an example. Imagine a page 3 cocktail party in a hall where all those invited are uniformly distributed across the floor, all talking to their nearest neighbors. Now this hall is our Higgs field and the invited people filling it are our Higgs bosons. Suddenly a famous film actress enters and crosses the room (she is our particle!). All are strongly attracted to her and cluster round her. As she moves she attracts the people she comes close to, while the ones she has left return to their even spacing. Because of the knot of people always clustered around her she acquires a greater mass than normal that is she has more momentum for the same speed of movement across the room. Once moving she is hard to stop, and once stopped she is harder to get moving again because the clustering process has to be restarted.
So in Higgs mechanism, In order to give particles mass, a background field is invented which becomes locally distorted whenever a particle moves through it. The distortion - the clustering of the field around the particle - generates the particle's mass. We need it because otherwise we cannot explain why the Z and W particles which carry the weak interactions are so heavy while the photon which carries electromagnetic forces is massless.
Theory of everything; the great unifying theory of all forces!
If bosons or force carrying particles of various forces do get their masses from interacting with the empty space, Higgs field (which in turn acts through Higgs bosons), then it plays a vital role in "unifying" these different forces
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