Bottom ScienceParticle Physics
Introduction
- Introduction to Particle Physics
- Need of High Energy Physics
- Four Fundamental Forces
- Units in High Energy Physics
- Natural System of Units
- Particle Accelerators & Types
- 1st, 2nd, and 3rd Generation Particles
- Center of Mass Frame vs. Laboratory Frame
- Gravitational vs Nuclear Binding Energy (Mass Defect)
Invariance Principles & Conservation Laws
- Symmetries & Conservation Laws
- Continuous Transformations
- Discrete Transformation
- Parity Transformation
- Wu’s Experiment & Parity Violation
- Feynman Rules for Quantum Electrodynamics (QED)
- Electron-Muon Scattering Amplitude (M) Calculation
- Electron-Positron Scattering Amplitude (M) Calculation
- SU(1), SU(2), SU(3) – Unitary Groups (QCD)
- More topics coming soon…
Problems
No. of Quark Flavors for Coupling Constant QCD = QED | Particle Physics | Problems
Problem – How many number of quark flavors exist in nature so that coupling constant α of QCD behave same as QED?
Solution
We know,
critical parameter (a) is given by
a = 2f – 11n
where
f = flavors
n = colors
so,
for a > 0, QCD and QED coupling constants behave the same way.
i.e.
> 0 = 2f – 11n
by choosing n =3 (colors),
= f > 16
= f $\geq$ 17
Hence there should be more than 16 flavors of quarks in 3 different colors.
