Mechanics: “Classical Mechanics” Classical Physics: Foundation of pure & applied macroscopic physics & engineering! Newton’s Laws + Boltzmann’s Statistical Mechanics (& Thermodynamics): Describe most of macroscopic world! However, at high speeds (v ~ c): Need Special Relativity. Ch. 7 Small size (atomic & smaller): Need Quantum Mechanics. Physics 5301! Classical Mechanics: 17th & 18th centuries, but still useful today!

Four Fundamental Forces Of Nature! Mechanics Science of HOW objects move (behave) under given forces. (Usually) Does not deal with sources of forces. Answers the question: Given the forces, how do objects move? Forces are classified into four types: Four Fundamental Forces Of Nature! Mechanics applies to all four!

4 Fundamental Forces of Nature Sources of forces: In order of decreasing strength Strong Nuclear Force: Binds nuclei together. Still being researched. Electromagnetic Force: E&M phenomena. Chemical forces. Most everyday forces. Maxwell, Coulomb, Ampere, Faraday, ... Weak Nuclear Force: Nuclear decay. Fermi, Bethe, others. Still being researched. Gravitational Force: Newton (classical mechanics) Einstein (general relativity)

4 Fundamental Forces of Nature Sources of forces: In order of decreasing strength

4 Fundamental Forces: Sources of forces “Electro-Weak” Force: Since ~ late 1960’s, in some sense have reduced the 4 fundamental forces to 3! Electromagnetic Force & Weak Nuclear Force combined into one theory. S. Weinberg & A. Salaam: 1972 Nobel Prize in Physics!

The Rest of Physics! Statistical Mechanics: (Physics 5305) What we’ve mentioned is  all of physics except: Statistical Mechanics: (Physics 5305) Mechanics of systems of huge numbers of particles (>> ~ 1023). Uses probability & statistics methods to compute macroscopic properties from microscopic force laws between particles. The major LINK between microscopic & macroscopic physics! Contains Thermodynamics as a sub-theory!