All the known particles in the universe are classified either as a boson or a fermion.
Bosons in quantum mechanics are what the fundamental forces are exchanged through. Bose-Einstein statistics is a theory of boson behavior. One amazing property is that multiple bosons can occupy the same quantum state.
Fermions don’t occupy the same quantum state simultaneously, this is why matter/materials have the characteristics of substance. The Pauli exclusion principle is a mathematical representation of this phenomenon.
The four fundamental forces of nature that are supposedly of The Unified Field are gravity, the strong force, the weak force and electromagnetism.
- Gravity is the effect of fermions and bosons following the geometrical curvature in the fabric of space-time. It’s the mass and energy of matter that warp the fabric of space-time. The more mass and energy there is, the more curvature there will be and the stronger the gravitational field. This is why when objects interact with other objects, the ones with more mass and energy dominate the attraction of the ones with less, like the Earth does to people or the sun to the Earth.
- The strong force binds quarks/fermions to form hadrons. Common hadrons are protons and neutrons, which are also called nucleons, because of the role they play in the nucleus of atoms. A residual from the bond of the strong force also binds protons and neutrons together to form nuclei. The force carrier/boson for the strong force is called the gluon and there are eight different types. Most of the mass in matter comes from the strong force.
- The weak force is the interaction and mechanism that causes the decay of particles. A couple examples are alpha and beta decay radiation. Alpha decay is when an atom releases two protons and two neutrons, which is also a helium nucleus. Alpha decay is the process of fusion. Beta decay is when a neutron decays into a proton, electron and anti-nutrino, also known as the process of fission. There are three force carrier particles for the weak force; the W+, W- and Z bosons.
- Electromagnetism consists of waves in electric and magnetic fields, simultaneously propagating together and alternating with each other through space-time. When electricity and magnetism each complete their own wave, they intersect with each other and the electric wave turns into a magnetic wave and at the same time, what was the magnetic wave turns into an electric wave. This alternating process is a constant that will go on forever at a speed of approximately 186,000 miles per second in a vacuum, as long as nothing interferes with it. In electromagnetism the fermion is the electron and the force carrier is the photon. By orbiting the nucleus, the electron is also an essential building block of the atom.
The weak and strong forces are short range, because their effects are internal to the atom. Gravity and electromagnetism are long range forces, because their effects can travel billions of light years. You may have noticed there was no mentioning of fermions or bosons for gravity. This is because although it makes sense that the fabric of space-time consists of these, experiments capable of detecting them haven’t been created yet. The postulated fermion is simply the gravity particle and the boson is the graviton.
Keep in mind this description is brief and within the modern paradigm, there has been unification bringing us closer to The Unified Field. More pieces have been added to the puzzle. Newer mysteries for gravity include dark matter and dark energy. Among other recent historical discoveries is the Higgs Boson in 2012, which is a key player in the standard model of particle physics, and gravitational waves in 2015, predicted by general relativity. All these exciting details and more will be covered in later sections.