What are the different components of physics?

Answer 1

Generally, Physics is broken into 2 sections: Classical and Modern... Then there are leagues of subgroups. Here are the main ones: Classical: Optics, Mechanics, Wave Physics, Electrodynamics/Magnetism, Thermal, Electricity. Special and General Relativity can fall into both depending on the depth you go into... this can be said for many of the different branches though However many of these have cross-overs, i.e. Quantum Electrodynamics - See work by Feynman, Quantum Optics etc Modern Physics is more hazy... Particle, nuclear, atomic, Quantum. The definition of modern physics could be generalized to anything that involves the quantization of energy (lumps of energy, rather than continuous). Many problems in modern physics are more accurate (not perfect) descriptions of classical things. For example, Newtons laws of motion work in everyday use, but when you get to about 5% of the speed of light the relativistic effects come into play. So although the Newtonian stuff is an approximation it works very well as long as the velocity is much less than c. Good examples of the segregation of modern and classical physics are things like the photoelectric effect (Einstein's nobel prize winning work) which shows how light must be a particle. Also, Young's' Double Slit experiment shows how light is a wave.. Hence, Wave-Particle Duality purposed in De Broglies (ridiculously short) PhD thesis.