Thermal Physics

General Foundation

The course is also offered to exchange programme students.

Α. Thermodynamics Upon successful completion of the course, students will be able to: - Understand and apply the fundamental laws of Thermodynamics to macroscopic systems. - Handle thermodynamic potentials, Legendre transformations, and Maxwell relations. - Solve problems related to thermodynamic processes in ideal and real systems. - Analyze phase equilibrium and use the Clausius–Clapeyron equation. - Distinguish the nature and order of phase transitions. -Describe and assess phenomena such as Joule and Thomson expansion, the piezoelectric effect, and the magnetocaloric effect. B. Statistical Physics Upon successful completion of the course, students will be able to: - Understand the statistical nature of Thermodynamics and relate macroscopic quantities to microscopic states. - Distinguish and apply the basic statistical ensembles: microcanonical, canonical, and grand canonical. - Calculate physical quantities such as energy, entropy, and heat capacity using statistical distributions. - Analyze paramagnetic systems and interpret phenomena such as negative temperature. - Formulate and apply the consequences of the second and third laws of Thermodynamics. - Describe the heat capacity of solids using the Einstein and Debye models. - Understand blackbody radiation and Planck’s law. - Apply classical statistical mechanics and the equipartition theorem. - Ιintroduced to quantum statistics and understand the Fermi–Dirac and Bose–Einstein distributions. - Analyze the behavior of ideal fermionic and bosonic gases, as well as Bose–Einstein condensation.

(A) THERMODYNAMICS - Axiomatic formulation of Thermodynamics: Axiomatic introduction to the laws of Thermodynamics. - Thermodynamic potentials: Thermodynamic potentials, Legendre transformations, Maxwell relations. Exercises. - Applications I – Study of simple systems: Relation between heat capacities, ideal gas, elastic rod, electrochemical cell, piezoelectric and magnetocaloric effects. Problems. -Applications II – Irreversible processes: Joule expansion, Thomson expansion. Problems. - Phase equilibrium: Thermodynamic equilibrium and equilibrium criteria. Multiphase systems (real pure substances), phase equilibrium, phase transitions, Clausius-Clapeyron equation. Order of phase transitions. Problems. (B) STATISTICAL PHYSICS - Axioms of Statistical Physics – Microcanonical ensemble: Equilibrium in an isolated system. - Canonical ensemble: Equilibrium of a system in a thermal reservoir. Partition function, Boltzmann distribution, energy, relative energy fluctuations, Helmholtz free energy. General definition of entropy. Problems using the microcanonical and canonical ensemble. - Paramagnetism: Paramagnetic material in a heat reservoir. Energy, entropy, heat capacity, magnetization, magnetic susceptibility. Isolated paramagnetic material. Negative temperatures. Problems. - Second Law of Thermodynamics for infinitesimal transformations. Third Law. Formulations and experimental verification. Adiabatic cooling. Problems. - Heat capacity of solids due to lattice vibrations: Einstein model. Density of states. Debye model. Problems. - Classical Ideal Gas: Energy, partition function, entropy, heat capacity, equation of state of a classical ideal gas, entropy of mixing (Gibbs paradox). Criterion for classical approximation. Classical statistical mechanics. Equipartition theorem. Problems. - Introduction to Quantum Statistics – Blackbody radiation: Photon partition function, Planck’s law, properties of blackbody radiation. Problems. - Ideal Quantum Gas: Quantum statistics – Grand canonical ensemble, Fermi-Dirac and Bose-Einstein distributions, classical limit. - Fermion gas: Free electron model in metals. - Bose-Einstein condensation: Bose gas at low temperature. Problems in quantum statistics.

Thermodynamic laws (1st, 2nd, and 3rd Law), Thermodynamic systems and processes, Thermodynamic potentials, Legendre transformations, Maxwell relations, Phase transitions, Phase equilibrium, Clausius–Clapeyron equation, Joule–Thomson expansion, Piezoelectric effect, Magnetothermal phenomena, Microcanonical, canonical, and grand canonical ensemble, Equilibrium states – Probabilities, Statistical entropy, Equipartition theorem, Boltzmann, Fermi–Dirac, and Bose–Einstein distributions, Classical and quantum statistics, Ideal gas, Paramagnetism, negative temperature, Blackbody radiation, Planck’s law, Einstein and Debye models for solids, Ideal fermionic and bosonic gases, Bose–Einstein condensation.

23-07-2025