PH-307 Thermal Physics  

  1. First law of thermodynamics, equilibrium, functions of state, internal energy; reversible changes, enthalpy, heat capacities, reversible adiabatic changes.
  2. Entropy, second law of thermodynamics, Carnot cycle; determination of entropy in irreversible processes, the approach to equilibrium.
  3. Microstates and macrostates, counting microstates, ensembles and ensemble averaging, approach to equilibrium.
  4. Classical probability, Statistical probability, axioms of probability theory, probability distributions, discrete and continuous distributions, binomial and Gaussian distributions, central limit theorem, combinatorics.
  5. Microcanonical systems, definition of a quantum state, entropy and equilibrium in a microcanonical system, the second law in statistical form (S=klnW)
  6. Canonical ensemble, partition function, entropy in canonical system, Boltzmann distribution, thermodynamical averages, applications to single particle, factorization of partition function.
  7. Equipartition theorem, free energy and its minimization, Gibbs and Helmholtz free energy and applications.  
  8. Maxwell distribution of molecular speeds, classical probability of a state, Maxwell-Boltzmann probability distribution, density of states in k-space, distribution of speeds in a classical gas.
  9. Black body radiation, Rayleigh-Jeans theory, Planck distribution, free energy of a photon gas, Stefan-Boltzmann formula, phonons.
  10. Systems with variable number of particles, chemical potential, grand canonical ensemble, relation to thermodynamic variables.
  11. Identical particles, fermions and bosons, partition function for identical particles, semi-classical approximations, identical particles localized on a lattice, thermodynamic properties of a Fermi gas, low and high temperature regions, Bose condensation, applications to neutron stars.

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