## Statistical Mechanics

**Statistical Mechanics (Spring 2013, Stanford Univ.)**. Instructor: Professor Leonard Susskind. Statistical mechanics is a branch of physics that applies
probability theory to the study of the thermodynamic behavior of systems composed of a large number of particles. Statistical mechanics provides a framework for
relating the microscopic properties of individual atoms and molecules to the macroscopic bulk properties of materials that can be observed in everyday life.
Thus it explains thermodynamics as a result of the classical and quantum-mechanical descriptions of statistics and mechanics at the microscopic level.
(from **theoreticalminimum.com**)

Lecture 01 - Entropy and Conservation of informationLeonard Susskind begins with a brief review of probability theory, and then presents the concepts of entropy and conservation of information. |

Lecture 02 - TemperatureLeonard Susskind presents the physics of temperature. Temperature is not a fundamental quantity, but is derived as the amount of energy required to add an incremental amount of entropy to a system. |

Lecture 03 - Maximizing entropyLeonard Susskind begins the derivation of the distribution of energy states that represents maximum entropy in a system at equilibrium. |

Lecture 04 - The Boltzmann distributionLeonard Susskind completes the derivation of the Boltzmann distribution of states of a system. This distribution describes a system in equilibrium and with maximum entropy. |

Lecture 05 - Pressure of an ideal gas and fluctuationsLeonard Susskind presents the mathematical definition of pressure using the Helmholtz free energy, and then derives the famous equation of state for an ideal gas: pV = NkT. |

Lecture 06 - Weakly interacting gases, heat, and workLeonard Susskind derives the equations for the energy and pressure of a gas of weakly interacting particles, and develops the concepts of heat and work which lead to the first law of thermodynamics. |

Lecture 07 - Entropy vs. reversibilityThe speed of sound in an ideal gas, A single harmonic oscillator in a heat bath, The second law of thermodynamics, Reversibility of classical mechanics, Chaos theory. |

Lecture 08 - Entropy, reversibility, and magnetismLeonard Susskind continues the discussion of reversibility by calculating the small but finite probability that all molecules of a gas collect in one half of a room. He then introduces the statistical mechanics of magnetism. |

Lecture 09 - The Ising modelLeonard Susskind develops the Ising model of ferromagnetism to explain the mathematics of phase transitions. The one-dimensional Ising model does not exhibit phase transitions, but higher dimension models do. |

Lecture 10 - Liquid-gas phase transitionProfessor Susskind continues the discussion of phase transitions beginning with a review of the Ising model and then introduces the physics of the liquid-gas phase transition. |

References |

Statistical Mechanics (Spring, 2013) | The Theoretical MinimumStatistical mechanics is a branch of physics that applies probability theory to the study of the thermodynamic behavior of systems composed of a large number of particles. |