Table of contents

A Special scientific session of the Editorial Board of the journal Uspekhi Fizicheskikh Nauk (an oral issue of the journal UFN) was held in the Conference Hall of the P N Lebedev Physical Institute, Russian Academy of Sciences (Moscow), on 3 October 2006. Several topical physical problems from the list given by Vitalii Lazarevich Ginzburg in his Nobel Lecture (Ginzburg's list) were discussed [in the order of the problems appeared on Ginzburg's list (see p. 332)].

The physical properties of hot dense matter over a broad domain of the phase diagram are of immediate interest in astrophysics, planetary physics, power engineering, controlled thermonuclear fusion, impulse technologies, enginery, and several special applications. The use of intense shock waves in dynamic physics and high-pressure chemistry has made the exotic high-energy-density states of matter a subject of laboratory experiments and enabled advancing by many orders of magnitude along the pressure scale to range into the megabars and even gigabars. The present report reviews the latest experimental research involving shock waves in nonideal plasmas under conditions of strong collective interparticle interaction. The results of investigations into the thermodynamic, transport, and optical properties of strongly compressed hot matter, as well as into its composition and conductivity, are discussed. Experimental techniques for high energy density cumulation, the drivers of intense shock waves, and methods for the fast diagnostics of high-energy plasma are considered. Also discussed are compression-stimulated physical effects: pressure-induced ionization, plasma phase transitions, the deformation of bound states, plasma blooming ('transparentization' of plasma), etc. Suggestions for future research are put forward.

The fundamental problems of cluster physics occupy seventh place in the V L Ginzburg classification of most important problems in modern physics and are discussed below.

The field of nonlinear physics, item No. 11 on Ginzburg's list of "the most important and interesting problems", is reviewed. An example at the intersection of applied physics, medicine, and instrument engineering is discussed to illustrate the range and scope of the field and how deep the ideas and approaches it involves are incorporated in modern natural science and engineering. Results of relevant research and development, which has attracted much recent interest and financial support, are briefly examined.

Undulators — periodic magnetic structures that were originally introduced by Vitalii Ginzburg in 1947 for electromagnetic radiation generation using relativistic electrons — are among the key elements of modern synchrotron radiation sources and free electron lasers (FELs). In this talk, the history of three generations of storage ring-based synchrotron X-ray sources using wigglers and undulators is briefly traced. Prospects for two types of next-generation space-coherent X-ray sources are discussed, which use long undulators and energy recovery accelerators or, alternatively, employ linear accelerator-based FELs. The recently developed Novosibirsk terahertz FEL facility, currently the world' s most powerful terahertz source, is described. It was the generation of electromagnetic radiation in this range that Ginzburg discussed in his 1947 work.

In their pioneering work on transition radiation, Ginzburg and Frank showed for the first time that a charge may radiate electromagnetic waves not only because of its accelerated motion but also because of time variation of the phase velocity of electromagnetic waves in the ambient medium. This result is of very general importance for physics. For example, a charge at rest can radiate in a nonstationary medium. Transition radiation is widely used in high-energy particle detectors, mainly for identification of ultrarelativistic electrons in accelerator and collider experiments.

This review describes the history of the discovery of the violation of the spatial parity P, the charge conjugation parity C, and the combined parity CP. The hypothesis of the existence of mirror particles was intended by its authors to restore the symmetry between left and right. The review presents the emergence and evolution of the concepts of 'mirror particles' and 'mirror matter' and can serve as a concise travel guide to 'mirror land.' An important part of the review is the list of about 200 references with their titles.

Current understanding of major unsolved problems in particle physics and cosmology suggests that physics is facing serious challenges and that the existing view of how the laws of Nature work may possibly (though not necessarily) be substantially extended in the near future. From this standpoint, experiments at the LHC proton collider due to start shortly at CERN are going to make a crucial impact.

Relations existing among "the three great problems" of physics (as enumerated by Ginzburg) — interpretation of quantum mechanics, the time arrow, and reductionism (reducing the phenomenon of life to physics) — are discussed and shown to substantially depend on how the first of them is solved, i.e., which interpretation of quantum mechanics is adopted. The Copenhagen interpretation, the Everett ('many-words') interpretation, and Extended Everett Concept proposed by the author are considered.

The concept of the interaction of an electrostatic field and plasma flows in a dusty plasma is reviewed. This approach helps to describe many aspects of dusty plasma physics. Of basic importance in this context are processes that plasma flows introduce into interactions between dust particles. Fluctuations in plasma flows, together with those in electrostatic fields, considerably modify these interactions, with the result that like-charged particles that are far apart start attracting one another, possibly leading to their pairing. Knowledge about the attraction between distant particles is traced from the early work of 1963 through modification and improvement to its present level, when it has become possible to qualitatively estimate the parameters of the dusty plasma — dust crystal transition, and to obtain the values for the coupling constant, dust particle separations, and the transition temperature consistent with observations. The self-energy of dust particles, exceeding both their kinetic energy and interaction energy, is discussed in terms of the role of its variations. Generation mechanisms and the role of regular plasma flows are examined. Self-excitation of regular and fluctuating plasma flows gives rise to structures such as dust voids, dust vortices, dust clumps, and helical dust structures. Self-organizing structures are frequently seen both in laboratory and natural conditions. Prospects for further research are addressed and problems yet to be solved reviewed.