by Marina KHALIZEVA, Science in Russia observer

Nuclear physicists marked the 85th birth anniversary of Boris Kadomtsev (1928-1998) in November of 2013. A lead nuclear physicist honored with State (1970) and Lenin (1984) Prizes, he is among the fathers of the theory of high-temperature plasma and controlled thermonuclear fusion (CTF). His works gained recognition worldwide and made him a leader of our theoretical school of hot plasma physics. Boris Kadomtsev was in the cohort of outstanding physicists who, with Lev Artsimovich at the head, pioneered in the theory of stationary systems with a thoroid magnetic field, the famous tokamaks.

Boris Kadomtsev spent his tender years in Penza, a large city in central Russia. Of inquisitive mind, he had a strong bent for natural sciences. As a magna cum laude high school graduate, in 1946, at age 16, he entered Moscow University where, attending lectures of Professor Igor Arnold on mathematics, he felt a strong interest in theoretical physics and structure of matter. Joining the Structure of Matter Department, he started learning the nuts and bolts of nuclear physics. Graduating from Moscow University with honors in 1951, the young physicist joined the Physics and Energy Institute at Obninsk, a

science town about 100 miles south of Moscow, where for as long as four years he kept working on theoretical problems of nuclear power under Dr. Dmitry Blokhintsev, a top nuclear physicist of the day. Boris Kadomtsev condensed his knowledge acquired there in his doctoral candidate dissertation presented in 1954.

Seeking to improve his mind and background, Kadomtsev began to attend the famous seminars of Lev Landau at which he, Kadomtsev, learned a good deal on science news. In 1955, among a small group of Obninsk nuclear physicists, he took part in the work of a national conference handling nuclear research problems held on the initiative of Igor Kurchatov* and attended by the flower of the national nuclear science. Kurchatov was heading the Soviet nuclear project. That conference was a turning point for Kadomtsev. "It all began with Kurchatov's vigorous, go-ahead speech," Kadomtsev wrote in his book of reminiscences. Not only fresh, imaginative ideas

* See: Ye. Velikhov, "Pride of Russian Science"; V. Sidorenko, "Pioneer of Soviet Atomic Power Engineering"; Yu. Sivintsev, "A Few Unforgettable Meetings"; R. Kuznetsova, V. Popov, "Scientific Heritage of Academician Kurchatov", Science in Russia, No. 6, 2012.--Ed.

and approaches were needed for attacking the problem of controlled nuclear fusion but also a broader involvement of young blood in tackling this grandiose problem so important for humanity's future... "The seminar impressed me immensely, and I firmed up in my decision that high-temperature plasma was the most interesting field of physics. I began cherishing plans to go over to LI PAN*."

The following year Kadomtsev joined a research team headed by Mikhail Leontovich, a man of great erudition who played a crucial part in high-temperature plasma studies and in rearing young physicists, such as Vitaly Shafranov, Stanislav Braginsky, Vladimir Kogan, Boris Trubnikov and Dmitry Sivukhin who had just begun digging into plasma physics, a new and fertile area of research. Kadomtsev found himself

* In 1943, in keeping with the decision of the USSR Academy of Sciences, No. 2 Laboratory was set up to handle the nuclear problem. In 1949, at Kurchatov's suggestion, it was reorganized into a Laboratory of Measuring Instruments, LIPAN in Russian abbreviation; in 1956 LIPAN became an Institute of Atomic Energy. After Kurchatov's death in I960 the Institute was named for him, and became the Kurchatov Institute. In 1991 it was reorganized again into the Russian Research Center "Kurchatov Institute" and then again, in 1991, into the National Research Center; then once again, in 2009, into the National Research Center "Kurchatov Institute".--Ed.

out in that collective, he was a perfect fit there. He was on the same wavelength with his fellow researchers. New bold and inventive ideas were born here, with the very climate propitious for their materialization. Already in the first few years as a member of the team Kadomtsev carried out pioneering research studies of convective plasma instability in a glow discharge and plasma convection in an open axially symmetrical trap. As another eminent nuclear physicist, Vitaly Shafranov, put it, Kadomtsev's research works "were milestones in CTF, for they debunked the bogy of 'Bohm's plasma diffusion'* in a magnetic field that seemed universal and inevitable and left no hope for the technical feasibility of a thermonuclear reactor."

Kadomtsev was out to explain the phenomenon of "self-organization" of non-equilibrium plasma in continual energy pumping. The first results of his inquisitions reported at the First Conference of the International Atomic Energy Agency (IAEA) on CTF and plasma physics (held in 1961 in Salzburg, Austria) brought him world fame. Kadomtsev concentrated then on the theory of cooperative processes in high-temperature plasma; he distilled his findings in a monograph that made him a top specialist in this important field of cooperative phenomena. In 1961 Kadomtsev defended his doctoral dissertation, and in 1962 was elected to the national Academy of Sciences as its corresponding member.

* Abnormally fast equalization of plasma particles concentration perpendicular to the lines of force of an outer magnetic field, a phenomenon first described in 1949 David Bohm of the United States.--Ed.

In the mid-1960s Kadomtsev turned to research into plasma instabilities in toroidal systems, the tokamaks and stellarators.* In his paper on plasma confinement in toroidal traps with failed magnetic surfaces (1967) he opted for tokamaks** as the best experimental tool since they made it easier to build closed magnetic surfaces. Thus, as Vitaly Shafranov stressed it time and again, Kadomtsev was the first to outline the idea of a technical feasibility of a thermonuclear reactor on the tokamak basis, and that spurred Lev Artsimovich*** as the head of the national CTF program in stepping up experimental research in the area. Tokamaks gained world recognition, especially in countries concerned with controlled thermonuclear fusion. The first CTF reaction was realized in 1970 on the T-3 tokamak at the Kurchatov Institute. Soon after, Kadomtsev was honored with full membership in the Science Academy.

Boris Kadomtsev had a style of his own. As Dr. Yuri Dnestrovsky, his colleague, confided, "Kadomtsev had an ambivalent relationship to computer technology. Although aware of the need of computers in dif-

* Traps having closed magnetic surface. Unlike the tokamak, the sellarator has its poloidal magnetic field induced by a current in external coils. Its idea was first proposed in 1951 by Lyman Spitzer, Jr., of the United States.--Ed.

** See: V. Strelkov, "Creator of the Tokamak", Science in Russia, No. 4, 2012; M. Khalizeva, "The Fate and Magic of Talent", Science in Russia, No. 3, 20I3.-Ed.

*** See: Ye. Velikhov, "Thermonuclear Combustion"; V. Strelkov, "No Royal Ride in Thermonuclear Research"; M. Petrov, "Talent Is Judged by Work", Science in Russia, No. 1, 2009.--Ed.

ficult problem solving, he never used them. He sought to bring out a simplest model and exterpolate it on plasma processes. That is, he saw the answer beforehand, and before developing an algorithm or a model he got down to the truth in a reasonable way. Although the intermediate stages could not be explained now and then, the upshot was always correct."

His great days in research came in the 1970s as Kadomtsev was working on plasma heating and confinement in a tokamak. His verve and go-aheadism in experiment, his eagerness to get down to the brass tacks in analysis and an ability of interpreting his results in pithy terminology revealed an impassioned researcher. At that time Kadomtsev authored his classical works on controlled nuclear fusion, such as On Stripping Instability in Tokamaks, and Tokamaks and Dimensionalities Analysis (1975), eye-opening in what concerned critical situations in CTF.

His inquisitive and inventive nature hankered for more than just one area of research, no matter how

intriguing and thrilling. We can see that in a two-volume edition of his selected works published posthumously in 2003 by PHYZMATLIT Publishers (concerned with physics and mathematics literature) with the financial backing of the Russian Foundation of Basic Research. What a staggering breadth of vision! In this edition we find works on high-temperature plasma and controlled nuclear fusion, on quantum mechanics, on mater in supermagnetic fields... on nonlinear and stochastic processes, solutions, ball lighting, and what not! In 1997 Kadomtsev produced a book titled Dynamics and Information dealing with a subtle relationship between dynamic systems and information processes (a problem closely related to quantum computers). This book had a phenomenal sale, and it had to be published again two years later in an edition twice as large. It sold out overnight again, snatched by "thoughtful readers" (a pat phrase with Kadomtsev for people eager to learn of what was new--a thinking bunch prone to get down to the heart of the matter).

Kadomtsev turned to way-out matters like that but now and then--for plasma physics was his forte and lifelong passion.

It became experimentally clear in the mid-1970s that tokamaks were a real thing. So the task of building an experimental reactor came to the fore, a reactor that could show a practical possibility of generat-

ing thermonuclear power and addressing related engineering problems. Yet there were doubts about the technical feasibility of such plans. Kadomtsev, he was on the other side of the barricade among the optimists, though he was clearly conscious that it was an uphill road full of snags that would call for concerted efforts of many insiders, bent on basic research. Small wonder that he supervised the national project of the world's first experimental reactor, the ITER (International Thermonuclear Experimental Reactor), an eloquent acronym to the Russian ear, syn-

* See: V. Glukhikh et al., "On the Brink of Thermonuclear Era", Science in Russia, No. 3, 2003; L. Golubchikov, "Tokamak--International Challenge", Science in Russia, No. 1, 2004; L. Smirnova, "Discoveries at the Large Hadron Collider", Science in Russia, No. 1, 2013.--Ed.

onymous with the abbreviation denoting people of the engineering and technological profession. According to Yevgeny Velikhov heading the ITER program, without his authority it would be pretty hard to move from pure physics to nuclear power.

It took as long as ten years to select a body of international experts for the project, and all that time it was the butt of controversy--was it science or power? It was on the horns of the dilemma. Policy-makers clinched the matter: an ITER agreement was reached in 1985 at a meeting of Mikhail Gorbachev and Ronald Reagan. Next, in 1988 and then in the 1990s the project was conceptualized and entered the design stage. It had to cross a thorny patch even at that

stage, but it made through between Scylla and Charybdis, largely thanks to Kadomtsev, a lead expert on tokamaks. He became the first chairman of ITER's Consultative Committee and helped in resolving so many deadlocks. The 1990s were especially bad, what with a financial crunch and shutdown in this country. That is why Russia was able to contribute but 3 percent of the total bill instead of the stipulated 25 percent. Nonetheless the ITER steering committee met us halfway, for it was clearly aware that the intellectual input of our nuclear physicists was commensurate with that of the other parties to the project, and even superior in some matters. So we had to redress the financial shortfalls by our brainwork.

Today peaceful uses of thermonuclear power are within reach: in 2006 ground was broken at Cadarache, France, for the ITER complex, with China, the European Union, Japan, Russia, South Korea and the United States taking part. Thus the many years of hard application by the world thermonuclear community fructified. Kadomtsev contribution is there as well. The first trial plasma experiments are slated for 2019 to be followed by full-scale tests as of 2027.

Boris Kadomtsev also taught at the Moscow Institute of Physics and Technology. He took his teaching activities in good earnest as his supreme duty. For a long time he was in charge of the Plasma Chair of the

Department of Physical and Molecular Chemistry there. His brilliant lectures in which he did his best to outline fundamentals of plasma physics were instrumental in forming a dedicated following of plasma physicists. In 1976 these lectures were summed up in a book on cooperative phenomena in plasma brought out by NAUKA Publishers. In 2001, that is after Kadomtsev's death, it was translated into English for the twenty-second volume of Reviews of Plasma Physics edited by Mikhail Leontovich.

His nonfiction book on pulsars (2001) was intended for college and high-school students. In it Kadomtsev described the physics of neutron stars, the pulsars. Presented in the conversational form, it belongs rather to popular science. Its English edition (2010) was recommended as reading matter by the American Association of Physics Teachers. Thanks to Rosolino Bucieri, an Italian astronomer, it was published in Italian too.

Kadomtsev also served as editor-in-chief of the Russian-published journal Uspekhi physicheskikh nauk dealing with physics updates. Its executive secretary, Maria Aksentieva, recalled his tender care and attention where the authors and their contributions were concerned. Always benevolent, he would never say anything bad. Only once he was unable to contain himself. "What a canaille!", he exploded. That was his worst in ten years as editor-in-chief. But he was well-meaning as a rule. "This man carries a positive sign"--he would speak about likeable people.

Kadomtsev, a minion of fortune. But no, that would be a bit thick. Actually he had a hard going. Fortune tested his fiber time and again. But he always came through with dignity. By his very nature--which was a given--Kadomtsev was an armchair scientist capable of consorting with only a few like-minded followers. Not a born leader he was to sway crowds. He was not after honors and fame. An egonaut, he was committed to science and craved to learn down to his last days.

Man supposes, God proposes. In 1973, with the death of Lev Artsimovich, Kadomtsev stepped into his shoes as head of a large collective involved with plasma. This research center (Institute of Nuclear Fusion) actually steered the national thermonuclear research program. He shouldered an awesome responsibility--the fates willed it so. As Yuri Dnestrovsky, his coworker, says that was at variance with his character makeup and frame of mind. Still, awake to this burden of responsibility, he carried on. He played a great part in the advancement of plasma physics, drawing in, bold, inventive ideas and fresh blood in abidance by the core stance of the Kurchatov Institute: find a happy mean between basic and applied science. Yevgeny Velikhov, our foremost nuclear physicist, hits the nail on the head: "Boris Borisovich [Kadomtsev], with his deep insight into the philosophy of science, its immanent development laws, and its orientation to a mission of practical application, sustained this atmosphere that helped the Kurchatov Institute to survive in the hard years of political and economic reform."

Kadomtsev forged many cooperative ties expanding the range of research programs of the Institute. At his initiative a new research department was set up there to look into the possibility of hybrid (combination) setups that could generate power through nuclear fusion and fission.

Administrative and managerial chores made heavy inroads on his time leaving but little elbowroom for science, a life issue to him. His colleagues saw him chafe under this burden, especially with the Soviet Union's breakup. He took it hard. In the early 1990s our country lost much of its science potential, and many can-do physicists working shoulder to shoulder with him, and his pupils had to seek fortune elsewhere rather than eke out a living at home, with Kadomtsev unable to help them out. His innate decency did not let him shake off the managerial load. Now add his sense of motivation and his yearning for individual creative work, and inability to help his collective over the hump of economic turmoil. This stressful situation was a cause of his untimely death. That is why Kadomtsev will live on also as a man of great moral commitment.