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Currently Playing: Space, Time and Vertices: the elements of a Feynman Diagram - Chapter 2 (High school Physics)

Feynman diagrams are a graphical representation of the processes involved in particle physics reactions. This video is the second episode of a series of three that presents what are Feynman diagrams, how to understand and use them, and how to build them. In this episode you will learn what are the elements you need to know to read Feynman diagrams and build your own: space-time diagrams, particle symbolism and vertices. We will use for this a well-known particle physics reaction as support, electron repulsion. We will also have a look at vertices involving the decay of a gluon into a quark and an anti-quark as well as the transformation of a quark and an anti-quark into a weak force boson. Feynman diagrams are an insightful tool that puts to light the wonders of particle physics. The reactions occurring in particle physics are a marvel of processes involving the forces of nature (weak force, strong force and electromagnetic force). Writing these like a chemical reaction does not provide information about the processes involved, just what you start up with, and what you end up with. One can use the Quantum Chromodynamics (QCD) and Quantum Electrodynamics (EOD) to model quite well what is going on, but the mathematics involved is not for everyone! Instead, graphical representation of these reaction, invented by Richard Feynman, allow all to visualize the processes involved easily: Feynman diagrams. He introduced these originally as a graphical aid for visualizing and calculating interactions between electrons and photons. Today, Feynman diagrams are commonly used to depict all types of particle interactions. These videos are intended to help high school students with their physics studies as well as high school physics teachers wondering how to approach the topic with their students. **** Access to the Videos **** Introduction: Content review of the Feynman Diagram mini-series: https://youtu.be/O9ihGuK53Ww Episode 1: What is a Feynman Diagram? (brief overview of Feynman diagrams, using as support a very well-known reaction, beta decay): https://youtu.be/TLBXrMixcu8 Episode 3: Feynman Diagrams, Let’s build some! (Learning how to build Feynman diagrams by example, using particle physics reactions like muon decay, pion decay, Kaon decay etc.: https://youtu.be/vgk2aJRlBcg SUPER USEFUL - The table of particles: https://www.physics-made-easy.com/Standard-Model-of-Particle-Physics If you are not familiar with Particle physics, I recommend you start by viewing the series of videos that deals in detail with particle physics reactions: _ Introduction: https://youtu.be/gy-durcAhJ4 _ Elementary and composite particles of the standard model: https://youtu.be/AJSL39hVVPw _ Quantum numbers of particles: https://youtu.be/3SVMrLmGHWQ _ Conservation laws and particle physics reactions: https://youtu.be/E4JGzQjBgHg Particle Physics Reactions PART 1 is a reminder of the standard model of particle physics. It presents the elementary particles (fermions like quarks and leptons, and bosons, like the photon or the gluon). It shows how combining some of them leads to composite particles (hadrons like the proton, the neutron, the pion and the kaon). Antimatter is also discussed in this section. Particle Physics Reactions PART 2 is a detailed look at some of the properties of these particles, which are expressed as quantum numbers (Baryon number, Electric Charge, Lepton number, Strangeness) Particle Physics Reactions PART 3: In nature there are some symmetries that need to be respected in all interactions, these leads to what we conservation laws. Quantum numbers need to follow these conservation laws. This idea is central. After viewing this section, you will be able to determine if a particle physics reaction is possible or not. For that, we will work on many examples of reactions including Beta decay, muon decay into a positron, and more. If you wish a slower paced and more in-depth review on the standard model of particles head on to these two videos: Elementary particles: https://youtu.be/guYfayO3ESI Composite particles: https://youtu.be/e-oyDDnI348 I hope these videos help you in getting a clear view on how to represent particle physics reactions using Feynman diagrams. - - - - - - - - - This video is produced and presented by Edouard Reny, Ph.D. in solid state chemistry and private tutor in Physics. For access to great resources that will help you with your studies of high school Physics, visit and subscribe to the "Physics Made Easy" website: https://www.physics-made-easy.com/ Edouard provides one-on-one private tuition in Physics (face to face or by Skype). If you wish to contact him, visit his website: https://www.physics-tutor.nl/