REVIEWS OF TOPICAL PROBLEMS

Berezinskii – Kosterlitz – Thouless transition and two-dimensional melting

V N Ryzhov, E E Tareyeva, Yu D Fomin, E N Tsiok

857

Hydrogen and its compounds under extreme pressure

A N Utyuzh, A V Mikheyenkov

886

Hot electrons in silicon oxide

V A Gritsenko

902

INSTRUMENTS AND METHODS OF INVESTIGATION

Negative ion adsorption by the ion source surface as a factor influencing ion lifetime measurements

V G Lukin, O G Khvostenko

911

FROM THE CURRENT LITERATURE

Retrograde motion of a rolling disk

A V Borisov, A A Kilin, Yu L Karavaev

931

METHODOLOGICAL NOTES

Quantum description of a field in macroscopic electrodynamics and photon properties in transparent media

I N Toptygin

935

CONFERENCES AND SYMPOSIA

Old and new in the physics of phase transitions (Scientific session of the Physical Sciences Division of the Russian Academy of Sciences, 21 December 2016)

948

Unconventional phase transitions in liquid crystals

E I Kats

949

Phase transformations in liquids and the liquid–gas transition in fluids at supercritical pressures

V V Brazhkin

954

Physics news on the Internet (based on electronic preprints)

Yu N Eroshenko

958