Dr. Bala explained about the basics of physics and different direction a researcher can take in physics. He also explained the seriousness in the research and value of mathematics in the research.
- Constituent of matter
- Small scale: Atom -> Nuclei + Electron -> Quarks -> ? (Strings)
- Big scale: Objects -> Planets -> Star -> Galaxy -> Universe
- Direction in physics:
- Classical Mechanics (first year of REAP)
- Special Relativity (2nd year of REAP)
- Quantum Mechanics (2nd year of REAP)
- Quantum Field Theory (QFT) or Particle Physics or High Energy Physics – Needs special tools like CERN LHC.
image source: wikipedia
- Forces present in the nature
- S – Strong interaction (responsible for binding the neutrons and protons inside the nuclei of atom)
- W – Weak Interaction (responsible for beta decay)
- G – Gravitation
- E – Electromagnetic
Only theory proposed for electromagnetic force is complete, for other 3 fundamental forces, their theories are incomplete.
Daily life is dominated by electromagnetic force.
Universe is dominated by gravity.
Two charges at static gives coulomb equation ~ 1/r2 * q1 * q2
Charges at movement gives rise to the current.
Acceleration in current gives rise to Radiation (EMW) – Light.
Electricity + Magnetism + Optics = Considered one in modern physics.
Different theories are formulated to provide answers for different speed and size scale such as
EM + W = Electromagnetic + weak
EW + S = Unified Grand Theory
EW + S + G = Super string theory