GRAVITATION, ASTROPHYSICS 
An analysis of the operation of a time machine

439

NUCLEI, PARTICLES, AND THEIR INTERACTION 
Measurement of the lifetime of a nucleus excited near a resonance

444

ATOMS, SPECTRA, RADIATION 
Dynamic polarizability and scattering of hf radiation by hydrogenic atoms

451

Interaction of ultrashort light pulses with a thin layer of surface atoms in twophoton resonance

457

Bifurcation and chaos in a system of optically coupled CO_{2} lasers

461

PLASMA, GASES 
Lightreflection spectrum of a turbid medium. Role of interference effects

467

Cyclotron absorption and emission in a strongly magnetized plasma

476

LIQUIDS 
Corresponding states law for quantum liquids

480

Dynamic susceptibility of magnetic liquids

498

SOLIDS 
Observation of KosterlitzThouless phase transition in the composite superconductor (NbTi)Cu

503

Supersymmetric description of the thermodynamics of a twodimensional lsing model with random exchange

512

Anharmonic theory of a phase with a spontaneously broken symmetry in erromagnets exhibiting an easyplane singleion anisotropy of arbitrary magnitude

516

Transverse electron focusing as a method for investigating the Andreev reflection

530

Features of resonance absorption, due to spinorbit interactions, by a system of twodimensional electrons

540

Mechanism of the superconductivity of twinning planes

546

Asymmetry of the scattering of polarized electrons by polycrystalline gold

556

Anomalous currentvoltage characteristics of tunnel junctions

561

Anomalies of magnetic properties of dilute Mn_{1x}Zn_{x}F_{2} and Ni_{1x}Mg_{x}F_{2} antiferromagnets below the percolation threshold

567

Electrodynamics of a Josephson medium in a hightemperature superconductor. Impedance in the mixed state

572

Dynamics of offdiagonal coherence in spin systems with restricted spectra

578

Singleelectron solitons in onedimensional tunnel structures

581

Electron structure and magnetooptics of ferromagnetic 3d metals

588

Alternatingcurrent conductivity of amorphous semiconductors (twosite model of small polarons)

597

Unusual nature of spin reorientation in HoFeO_{3}

604

Effect of dissipation on the lowtemperature properties of a tunneljunction chain

609

Correlation properties of atomiccollision cascades and athermal annealing of defects

619

Currentvoltage characteristic and critical currents in weak magnetic fields in YBa_{2}Cu_{3}O_{7δ}

625

Anomalies of highfrequency magnetic properties and new orientational transitions in HoFeO_{3}

629

Time dependence of the magnetic moment of hightemperature superconductors

639

Fluctuations of the hopping conductance of onedimensional systems

642

Lowtemperature noise in disordered systems in a wide temperature range

648

Density of states of twodimensional electrons in the presence of a magnetic field and a random potential in exactly solvable models

654

Raman scattering of light by electrons in a metal with impurities

661

ERRATA 
Erratum: A hydrogen atom in weak magnetic fields [Sov. Phys. JETP 57,770773 (April 1983)]

664
