1. Welcome to Physics 5305 Statistical Physics!

2. Brief Overview of the Structure of Physics
Where does Statistical Physics fit in to the overall organization (structure) of Physics?
What about Thermodynamics?
How is Thermodynamics related to Statistical Physics?

3. Niels Bohr 1922 Nobel Prize in Physics for
Occasionally, I’ll make comments on Physics History, Famous Physicists & Physics Trivia (interesting to me!)
Niels Bohr
1922 Nobel Prize
in Physics for
“His services in the
investigation of the
structure of atoms &
of the radiation
emanating from them.”

4. *Harald Bohr later became a famous mathematician!
Interesting Trivia (to me)! Niels Bohr is the only Nobel Prize Winner to have ALSO been an Olympic Medalist!
In the 1908 Olympics, he
& his brother Harald* were on the Danish soccer team, which won a sliver medal!
*Harald Bohr later became a famous mathematician!

5. Interesting Trivia (to me)
Interesting Trivia (to me)! Neils Bohr’s son, Aage Bohr also received a Nobel Prize in Physics!
He shared the 1975 Nobel Prize with B. Mottelson & J. Rainwater 
“for the discovery of the connection between collective motion & particle motion in atomic nuclei & the development of the theory of the structure of the atomic nucleus based on this connection”.

6. Overview of The Structure of Physics: Where do Statistical &Thermal Physics fit in to the structure & organization?

7. The Structure of Physics
Classical Physics is The Foundation
of pure & applied (macroscopic) physics & engineering!
Newton’s Laws + Electromagnetism
+ Statistical Mechanics + Thermodynamics.
(The Latter Topics are what this course is about!)
These together give a good description of most of the macroscopic world.
Classical Mechanics
(Newton, Lagrange, Hamilton,..)
The Physics of the 17th & 18th Centuries.
Still useful in the 21st Century!!

8. Special (& General) Relativity
Physics Structure
Classical Electromagnetism & Optics
(Newton, Coulomb, Gauss, Ampere, Faraday, Maxwell,..)
The Physics of the 18th & 19th centuries.
Still useful in the 21st Century!
High Speeds (v ≤ ~ c) 
Special (& General) Relativity
(Einstein, ..) 20th Century Physics!

9. Small Size (atomic & smaller):
Physics Structure
Small Size (atomic & smaller):
Quantum Mechanics
(Bohr, Schrödinger, Heisenberg….)
20th century physics!
Relativity + Quantum Mechanics:
Relativistic Quantum Mechanics
(Dirac,…) 20th century physics!
Quantum Field Theory
(Feynman, Schwinger, ..) 20th century physics!

10. “Mechanics” The 4 Fundamental
HOW objects move (behave) under given forces.
(Usually) Does not deal with the sources of forces.
Answers the question:
Given the forces, how do objects move?
Forces in the universe are classified into 4 types:
The 4 Fundamental
Forces Of Nature!
Some version of Mechanics
applies to all four!

11. The Strong Nuclear Force: The Electromagnetic Force:
The 4 Fundamental Forces of Nature The sources of the forces, in order of decreasing strength
The Strong Nuclear Force:
Binds nuclei together. Explained by the “Standard Model” & Quantum Chromodynamics. Still being researched.
The Electromagnetic Force:
E&M phenomena. Chemical forces. Most everyday forces. Maxwell, Coulomb, Ampere, Faraday, ...
The Weak Nuclear Force:
Nuclear decay. Fermi, Bethe, others. Electroweak Theory.
The Gravitational Force:
Newton (classical mechanics),
Einstein (general relativity), Hawking….

12. The 4 Fundamental Forces of Nature The sources of the forces, in order of decreasing strength

13. The Four Fundamental Forces
The “Electro-Weak” Force
Since ~ the late 1960’s, in some sense,
the 4 fundamental forces
have been reduced to three!
The Electromagnetic Force & the Weak Nuclear Force were combined into one theory. This was done by S. Weinberg & A. Salaam. For this work, they received the
1972 Nobel Prize in Physics!

14. The Standard Model of Particle Physics
“Periodic Table for Elementary Particles”! Quantum Chromodynamics (QCD) & the Electroweak Theory
Protons & Neutrons consist of 3 Quarks each.

15. The Standard Model

16. The Standard Model

17. The Standard Model

19. The Rest of Physics! Statistical Mechanics: Stat Mech:
What we’ve mentioned so far is  all of physics except:
Statistical Mechanics:
(This course ≡ “Stat Mech” )
“Stat Mech” is the mechanics of systems of
huge numbers (>> ~ 1023) of particles.
Stat Mech:
1. Uses Probability & Statistics to calculate macroscopic properties from microscopic force laws.
2. Applies to BOTH the Classical & the Quantum worlds!
3. Is the major link between microscopic & macroscopic physics!
4. Contains Thermodynamics as a sub-theory!