Elementary Particle Physics for Nerds Part 1
Class we will now talk about the politics of the quantum realm.
This series aims to educate readers on the knowledge of Elementary Particle Physics and to help set a foundation for any aspiring physicist or an interested reader. I am an undergraduate physics student and I would love to share my knowledge.
Introduction to Elementary Particles
Why are Elementary Particles important? How does this affect us? This is a question that has been in the minds of many people around the world. Understanding and finding these particles can help us answer the biggest questions of humanity like: “What is matter made of?”, “What is the Universe made of?”, “Are we made by God?”. These are some of the questions which plague many physicist’s nightmares including mine.
Elementary particles are on the size of the subatomic level, they are just tiny little chunks with vast space in between them. All of these particles are used to make up the things we can see, feel, taste, smell, and hear. This is extremely mind blowing!
These particles are extremely tiny and move at speeds near the speed of light. This is an issue because the particles that are moving very fast and are very tiny break apart the laws of classical mechanics also known as Newtonian mechanics. Newtonian mechanics is the laws of physics which govern the space we can perceive in a normal distance scale such as when pushing a car. We can calculate the force on the car and how fast it is accelerating and its speed from Newton’s laws of motion such as F=ma. Thus new theories need to be proposed and tested to match the results we obtain. Three new fields were then born to help us understand matter under various conditions such as: travelling at the speed of light — Relativistic Mechanics —, when the particles are extremely small (atoms, electrons, photons, etc) — Quantum Mechanics —, and when they are both travelling near the speed of light and are extremely small — Quantum Field Theory.
For this series you do not need a working knowledge of Quantum Field Theory and such because these are topics that usually come up during senior semester of undergrad and in grad school.
How do you “Produce” Elementary particles?
Now that you have been properly introduced to the topic, the next step is producing and detecting these Elementary Particles. Electrons and protons are easy to produce since they are stable and ordinary constituents of matter. What about the others?
- Cosmic rays: The Earth constantly bombarded by high energy particles from outer space. The source is unknown. When they hit the atmosphere they create a shower of many particles, mostly muons and neutrinos.
- Nuclear reactors: When nuclear fission occurs, the disintegration of nuclei releases a variety of particles.
- Particle accelerators: You accelerate electrons or protons to high energies and collide them together. This produces a shower of particles.
Some of you must have wondered why physicists push particles to higher energies and speeds and collide them. In quantum mechanics there is an important law known as Heisenberg’s uncertainty principle.
Heisenberg uncertainty principle states that △x△p ≥ h/(4*pi). Which means that we cannot know both the position and the momentum of the particle. Thus the more we know about space the less we know about the momentum. So here if we want to study an interaction in very minute spatial distances then the momentum must increase. Thus creating highly energetic particles to study interactions within a small spatial distance.
How do you detect Elementary particles?
We have understood about producing elementary particles, then what about detecting them? There are many kinds of particle detectors like Geiger counters, cloud chambers, spark chambers, bubbles chambers, scintillators, etc.
In a modern detector it actually has a whole array of such devices, these are then wired up to the computers which track the particles, their trajectories and collisions.
Now you have been properly introduced to Elementary particles, from what they are, their importance, to their productions and detection. We will next talk about “The Historical Introduction to the Elementary Particles”.
I hope you had a nice read, and will continue forward.
