Graduate course · UNIST · Fall 2026

Statistical Mechanics

From multiplicity to Bose condensation: how probability becomes thermodynamics.

The problem bank defines the level of the course.

There is no graded homework and no quiz series. Problems are for practice and are not submitted. Each examination contains four substantial problems, one from each bank block. Problems are taken from the bank or are close variants: the physical idea and method are familiar; details may change.

Lectures
Monday & Wednesday · 75 minutes · 13:00–14:15
Teaching assistant
Da Hyung Kim · kdahyung0805@unist.ac.kr
TA sessions
Most Wednesdays · one selected problem in the last ~20 minutes; two longer review sessions before the midterm and final
Student questions
Please contact the teaching assistant first for routine questions about course material and problems.
Blackboard
Course communication and materials as needed
Exams
The TA assists with midterm and final logistics and grading.
Homework
No weekly homework to collect or grade.
Textbook
Pathria & Beale, Statistical Mechanics, 3rd ed.

Seven chapters

  1. 1
    The statistical basis of thermodynamics Microstates, entropy, equilibrium, ideal gas, Gibbs paradox.
  2. 2
    Elements of ensemble theory Phase space, Liouville theorem, microcanonical ensemble.
  3. 3
    The canonical ensemble Boltzmann weights, partition functions, fluctuations, equipartition, virial theorem.
  4. 4
    The grand canonical ensemble Chemical potential, fugacity, particle-number fluctuations, phase equilibrium.
  5. 5
    Formulation of quantum statistics Density matrix, indistinguishability, symmetric and antisymmetric states.
  6. 6
    The theory of simple gases Maxwell–Boltzmann, Bose–Einstein, Fermi–Dirac, occupation numbers, internal motion.
  7. 7
    Ideal Bose systems Bose–Einstein condensation and blackbody radiation.

Calendar

Date Material
Aug 31 – Sep 9Chapter 1 · statistical basis of thermodynamics
Sep 14 – Sep 16Chapter 2 · ensemble theory
Mon Sep 21TA problem session · no new material
Sep 23 – Oct 12Chapter 3 · canonical ensemble
Mon Sep 28No class · UNIST Foundation Day
Mon Oct 5No class · substitute public holiday
Wed Oct 14TA-led midterm review · no new material
Oct 19 & Oct 21Exam week · no lecture
Oct 26 – Nov 4Chapter 4 · grand canonical ensemble
Nov 9 – Nov 18Chapter 5 · formulation of quantum statistics
Nov 23 – Nov 30Chapter 6 · theory of simple gases
Dec 2 – Dec 7Chapter 7 · ideal Bose systems
Wed Dec 9TA-led final review · no new material

Lecture notes

The seven handwritten lecture sets follow the seven Pathria chapters used in the course. They are the lecture backbone; corrections, if needed, will be made in class.

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7

Working rule

Students may use books, discussion, computation, and AI while studying the problem bank. The point is to learn the physics, not to certify a take-home solution.

Assessment occurs in the closed examinations. Attendance and missed examinations are handled according to UNIST regulations.