Introductory words about the course and teaching physics at MIPT, some basic experiments, the definition of the Cartesian coordinate system.
Crystal structure of solids, the translational symmetry of crystals, Bravais lattice, the elementary and primitive cell Wigner-Seitz basis. X-ray and neutron methods of investigation of the crystal structures, the Bragg diffraction, reciprocal lattice, Bragg plane Brillouin zone. Types of bonds in crystals: Coulomb (ionic crystals), the exchange interaction (atomic crystals), van der Waals (molecular crystals), metal (metals). Concept of quasicrystals. Lattice defects: point, linear (dislocations), flat, three-dimensional.
The statistical nature of the radiation. Quasi-monochromatic wave. Interference of quasi-monochromatic waves. Temporal coherence. Coherence time and "width" of the spectrum. Uncertainty relation. The maximum path difference in interference experiments.