Vladimir Gribov
Encyclopedia
Vladimir Naumovich Gribov (Russian
Russian language
Russian is a Slavic language used primarily in Russia, Belarus, Uzbekistan, Kazakhstan, Tajikistan and Kyrgyzstan. It is an unofficial but widely spoken language in Ukraine, Moldova, Latvia, Turkmenistan and Estonia and, to a lesser extent, the other countries that were once constituent republics...

 Влади́мир Нау́мович Гри́бов; March 25, 1930, Leningrad
Leningrad
Leningrad is the former name of Saint Petersburg, Russia.Leningrad may also refer to:- Places :* Leningrad Oblast, a federal subject of Russia, around Saint Petersburg* Leningrad, Tajikistan, capital of Muminobod district in Khatlon Province...

August 13, 1997, Budapest
Budapest
Budapest is the capital of Hungary. As the largest city of Hungary, it is the country's principal political, cultural, commercial, industrial, and transportation centre. In 2011, Budapest had 1,733,685 inhabitants, down from its 1989 peak of 2,113,645 due to suburbanization. The Budapest Commuter...

) was a prominent Russian theoretical physicist, who worked on high-energy physics, quantum field theory and the Regge theory
Regge theory
In quantum physics, Regge theory is the study of the analytic properties of scattering as a function of angular momentum, where the angular momentum is not restricted to be an integer but is allowed to take any complex value...

 of the strong interactions.

His best known contributions are the pomeron
Pomeron
In physics, the pomeron is a Regge trajectory, a family of particles with increasing spin, postulated in 1961 to explain the slowly rising cross section of hadronic collisions at high energies.-Overview:...

, the DGLAP
DGLAP
DGLAP are the authors who first wrote the QCD evolution equation of the same name. DGLAP was first published in the western world by Altarelli and Parisi in 1977, hence DGLAP and its specialisations are sometimes still called Altarelli-Parisi equations...

 equations, and the Gribov copies.

Life

Gribov completed his studies at the university of St. Petersburg (then Leningrad) in 1952, but at first he could find no employment there because of his Jewish background, so he spent two years teaching at an evening institute. In 1954 he joined the Ioffe Institute in Leningrad (then called the Physical-Technical Institute, PTI), and soon became the de-facto leader of the theoretical department.

in the late 1950s, he participated in Lev Landau
Lev Landau
Lev Davidovich Landau was a prominent Soviet physicist who made fundamental contributions to many areas of theoretical physics...

's famous weekly seminars in Moscow, where he met Isaak Pomeranchuk
Isaak Pomeranchuk
Isaak Yakovlevich Pomeranchuk was a Soviet physicist, who was the founder and first head of the theory division at ITEP. The particle pomeron is named in his honour. For his work, Pomeranchuk was twice awarded Stalin Prize .-External links:**...

, who he greatly admired and with whom he collaborated intensely. When the PTI theory department where Gribov worked, became a part of the Leningrad Institute for Nuclear Physics (LNPI) in 1971, Gribov became responsible for leading a seminar on quantum field theory and elementary particle physics. This seminar became famous both within the Soviet Union and internationally, because of its open-ended discussions, where prominent Russian scientists often voiced vigorous objections and debated points with the speaker and with one another. In these debates, each participant was treated equally regardless of position and reputation— the only thing that mattered was the physics. Foreign guests, no matter how prestigious, would often find themselves interrupted and corrected by Gribov in mid-lecture.

Although Gribov was most interested in elementary particle physics, he enjoyed discussing problems from all fields of physics and drew many inspirations from solid-state physics. One of the principles at his institute was that a theorist should never refuse to help an experimentalist.

Gribov was not an open dissident, but he had a reputation as an independent and critical thinker. So despite his international recognition, Gribov was not allowed to travel abroad for many decades .

In 1980, Gribov became a professor at the Landau Institute for Theoretical Physics
Landau Institute for Theoretical Physics
The L. D. Landau Institute for Theoretical Physics of the Russian Academy of Sciences is a research institution, located in the small town of Chernogolovka near Moscow...

 in Moscow
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...

, and in the 1990s he was also appointed a professor at Eötvös Loránd University in Budapest
Budapest
Budapest is the capital of Hungary. As the largest city of Hungary, it is the country's principal political, cultural, commercial, industrial, and transportation centre. In 2011, Budapest had 1,733,685 inhabitants, down from its 1989 peak of 2,113,645 due to suburbanization. The Budapest Commuter...

. Towards the end of the 1990s he was a visiting professor at the Institute for Nuclear Physics in the University of Bonn
University of Bonn
The University of Bonn is a public research university located in Bonn, Germany. Founded in its present form in 1818, as the linear successor of earlier academic institutions, the University of Bonn is today one of the leading universities in Germany. The University of Bonn offers a large number...

. He received the 1991 Sakurai Prize
Sakurai Prize
The J. J. Sakurai Prize for Theoretical Particle Physics, is presented by the American Physical Society at its annual "April Meeting", and honors outstanding achievement in particle physics theory...

, the 1991 Alexander von Humboldt Prize
Humboldt Prize
The Humboldt Prize, also known as the Humboldt Research Award, is an award given by the Alexander von Humboldt Foundation to internationally renowned scientists and scholars, and is currently valued at € 60,000 with the possibility of further support during the prize winner's life. Up to one...

, and was the first recipient of the Landau Prize awarded by the Soviet Academy of Sciences. He was a member of the American Academy of Arts and Sciences
American Academy of Arts and Sciences
The American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...

 and a corresponding member of the Russian Academy of Sciences
Russian Academy of Sciences
The Russian Academy of Sciences consists of the national academy of Russia and a network of scientific research institutes from across the Russian Federation as well as auxiliary scientific and social units like libraries, publishers and hospitals....

.

He was twice married and together with his first wife, Lilya Dubinskaya, had a son Lenja Gribov. Lenja died in a mountaineering accident shortly after completing his PhD in theoretical physics, a tragedy which weighed on Gribov heavily. His second wife, Julia Nyiri, was Hungarian.

Work

Gribov founded and led an influential school of theoretical elementary particle physics in Leningrad. He was widely admired for his physical intuition, which was often compared to that of two other prominent members of the Landau seminar Arkadi Migdal and Isaak Pomeranchuk
Isaak Pomeranchuk
Isaak Yakovlevich Pomeranchuk was a Soviet physicist, who was the founder and first head of the theory division at ITEP. The particle pomeron is named in his honour. For his work, Pomeranchuk was twice awarded Stalin Prize .-External links:**...

.

In the late 1950s and early 1960s, Gribov recognized an inconsistency in the then popular model of the strongly interacting particles as diffracting black-disks, and replaced this hypothesis with the pomeron
Pomeron
In physics, the pomeron is a Regge trajectory, a family of particles with increasing spin, postulated in 1961 to explain the slowly rising cross section of hadronic collisions at high energies.-Overview:...

, a description of maximum possible interaction which is relativistically consistent. He went on to formulate the Reggeon field theory, a perturbative framework for analyzing reggeon
Regge theory
In quantum physics, Regge theory is the study of the analytic properties of scattering as a function of angular momentum, where the angular momentum is not restricted to be an integer but is allowed to take any complex value...

 exchange .

In quantum field theory, Gribov was instrumental in understanding how Regge behavior emerges from field theories which are described by point-particles. He developed the parton model with a different focus than Richard Feynman
Richard Feynman
Richard Phillips Feynman was an American physicist known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics and the physics of the superfluidity of supercooled liquid helium, as well as in particle physics...

, using partons to give a qualitative description of the Pomeron as a diffusive process. close collaborators went on to formulate a perturbative description of the closely related hard pomeron within QCD.

Gribov was the first to note that covariant gauge fixing in a non-abelian gauge theory leaves a large amount of gauge freedom unfixed, which separates the Gauge field phase space into oddly shaped regions called Gribov copies which have the property that it is difficult to stay in any one copy while randomly walking around field space. Gribov noted that this is crucial for gluon confinement, since a mass gap precisely means that the field fluctuations are of a bounded size. This insight played a crucial role in Feynman's semi-quantitative explanation for the confinement phenomenon in 2+1 dimensional nonabelian gauge theory, a method which was recently extended by Karbali and Nair into a fully quantitative description of the 2+1 dimensional nonabelian gauge vacuum.

In collaboration with Lev Lipatov
Lev Lipatov
Lev Nikolaevich Lipatov is a Russian physicist, well known for his contributions to nuclear physics. He is the head of Theoretical Physics Division at St. Petersburg's Nuclear Physics Institute of Russian Academy of Sciences in Gatchina...

, he developed in 1971 an influential theory of logarithmic corrections to deep-inelastic lepton-hadron scattering and electron-positron hadron-production, using evolution equations for the structure functions of the hadrons, the quark - gluon distribution functions. This was a foundational advance in perturbative QCD . This work was extended by Altarelli and Giorgio Parisi
Giorgio Parisi
Giorgio Parisi is an Italian theoretical physicist. He is best known for his works concerning statistical mechanics, quantum field theory and various aspects of physics, mathematics and science in general....

 and is still very active today.

In his last years, Gribov was attempting to construct a theory for quark confinement based on a rough analogy to the electromagnetic phenomenon of maximum nuclear charge.

External links


Publications

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