It is frequently stated that the Ancient Greeks were the first to recognize objects that have no size but are capable of constructing the world around us through their interactions. And, as we become more capable of observing the world in ever-increasing detail through increasingly powerful microscopes, it’s only natural to question what these objects are made of.
We believe we have discovered some of these objects: subatomic particles, sometimes known as fundamental particles, which have no substructure since they have no size. We’re now trying to figure out how to explain the qualities of these particles and how they can be utilized to explain the universe’s contents.
The universe around us is made up of two sorts of fundamental particles: matter particles and force particles, one of which, the photon, is responsible for electromagnetic radiation. These are categorised in the standard model of particle physics, which theorizes how fundamental forces regulate the interactions of matter’s basic building elements. Fermions are matter particles, while bosons are force particles.
Quarks and leptons are two types of matter particles
There are two types of matter particles: quarks and leptons. There are six types of quarks and leptons, each having a corresponding partner.
There are three types of leptons. Each pair has a charged elementary particle and a non-charged elementary particle that is much lighter and more difficult to detect. The electron and electron-neutrino are the lightest of these couples.
Electric currents are caused by charged electrons. The uncharged counterpart, known as the electron-neutrino, is abundant in the Sun and interacts so weakly with its environment that it passes through Earth unharmed. Every second, a million of them move through every square millimeter of your body, day or night.
During supernova explosions, enormous amounts of electron-neutrinos are produced, and it is these particles that distribute elements formed by nuclear fusion into the universe. Carbon, from which we are produced, oxygen, which we breathe, and practically everything else on Earth are examples of these elements. Despite their aversion to interacting with other fundamental particles, neutrinos are essential for our survival. The other two neutrino pairs (named muon and muon neutrino, tau and tau neutrino, and tau and tau neutrino, respectively) appear to be heavier copies of the electron.
Because these particles are not found in regular matter, they may appear to be an unneeded complication. They did, however, play a critical part in forming the structure of the universe in which we live during the first one to ten seconds after the Big Bang, known as the Lepton Epoch.
The six quarks are also divided into three groups with amusing names: “up” and “down,” “charm” and “weird,” and “top” and “bottom” (originally “truth” and “beauty,” but regretfully changed). The protons and neutrons, which are at the heart of every atom, are made up of up and down quarks that bind together. Only the lightest pair of quarks is found in normal matter; the charm/strange and top/bottom pairs, like the heavier leptons, appear to play no role in the universe as it currently exists, but they did play a role in the universe’s early moments and helped to create one that is amenable to our existence.
Particles of force
The interactions between matter particles are created by six force particles in the standard model. Gravitational, electromagnetic, strong, and weak forces are the four fundamental forces.
A photon is a light particle that is responsible for the creation of electric and magnetic fields when photons are exchanged from one charged item to another.
The gluon generates the force that holds quarks together to create protons and neutrons, as well as the force that holds those protons and neutrons together to form heavier nuclei.
The “W plus,” “W minus,” and “Z” – known as intermediate vector bosons – are responsible for radioactive decay and the processes that cause the Sun to shine. The graviton, a sixth force particle, is thought to be responsible for gravitation, however it has yet to be detected.
The science fiction reality of anti-matter
Anti-matter is also something we’re aware of. This is a popular concept among science fiction writers, yet it does exist. Anti-matter particles have been observed regularly. In medicine, for example, the positron (the anti-particle of the electron) is employed in positron emission tomography to map our interior organs (PET). When a particle collides with its anti-particle, they both annihilate one other, resulting in a blast of energy. This is detected with a PET scanner.
Because each of the matter particles above has a partner particle with the same mass but the opposite electric charge, we may multiply the number of matter particles (six quarks and six leptons) to get a total of 24.
We assign a value of +1 to matter quarks and -1 to anti-matter quarks. The net number of quarks in the universe is calculated by adding the number of matter quarks and the number of anti-matter quarks; this number never changes. We can make any of the matter quarks if we have enough energy, as long as we also make an anti-matter quark. These particles were formed continuously in the early moments of the cosmos; presently, they are only created when cosmic rays collide with the atmospheres of planets and stars.
The well-known Higgs boson
In what is known as the standard model of particle physics, there is a last particle that completes the list of particles mentioned thus far. It’s the Higgs boson, predicted by Peter Higgs 50 years ago and discovered at CERN in 2012, earning Higgs and Francois Englert the Nobel Prize.
The Higgs boson is an unusual particle because it is the second heaviest of the standard model particles and defies simple explanation. It is frequently referred to as the source of mass, which is correct yet confusing. It supplies mass to quarks, and quarks make up protons and neutrons, although quarks account for only 2% of the mass of protons and neutrons, with the remainder coming from gluon energy.
We’ve accounted for all of the particles necessary by the standard model at this point: six force particles, 24 matter particles, and one Higgs particle, for a total of 31 fundamental particles. Despite what we know about them, their properties haven’t been studied thoroughly enough to state clearly that these particles are all that’s required to create the world we see around us, and we certainly don’t have all the answers. We’ll be able to refine our measurements of some of these features with the next run of the Large Hadron Collider, but there’s more.
Nonetheless, the theory is incorrect
The standard model, which is a wonderful theory, has been tested and retested for two decades and more, and we have yet to make a measurement that contradicts our predictions. However, we know that the traditional model is incorrect. When two fundamental particles contact, a variety of results are possible. Our theory allows us to compute the likelihood of any given result, but at energies beyond our current capabilities, it predicts that some of these scenarios will occur with a probability of greater than 100%, which is patently absurd.
Theoretical physicists have spent a lot of time and effort trying to come up with a theory that produces rational answers at all energies while also delivering the same answer as the standard model in every situation where it has been tested.
The most prevalent alteration implies that there are extremely heavy particles that have yet to be discovered. Because they are hefty, a lot of energy will be required to manufacture them. These new particles’ attributes can be adjusted to ensure that the final theory delivers reasonable answers at all energies, but they have no effect on the measurements that match the standard model so well.
Depending on whose theory you believe, the quantity of these undiscovered and as-yet-unseen particles varies. Supersymmetric theories are the most common type of these theories, and they indicate that all of the particles we’ve seen have a far heavier counterpart. If they are too heavy, however, issues will occur at energy that we can produce before finding these particles. However, the energy attained in the next run of the LHC will be so high that the absence of new particles will be a blow to all supersymmetric theories. The Discussion