The Vavilov Encounter, 1946
In 1946, a young Giyas Umarov traveled from Tashkent to Leningrad with the ambition of pursuing graduate studies in nuclear physics. The journey itself was an act of determination — Central Asian scientists were rare in the elite physics institutions of Leningrad and Moscow.
On the steps of the university, Umarov had a chance encounter that would alter the course of his career. He met Academician Sergei Ivanovich Vavilov, the President of the USSR Academy of Sciences and a towering figure in Soviet optics and luminescence research. Vavilov, recognizing the young man's talent and ambition, personally facilitated his admission to the Radium Institute under the direction of Academician V.G. Khlopin.
At the Radium Institute, an early laboratory demonstration went wrong. Instead of dismissing the young graduate student, Khlopin quipped: "That's called the Visit Effect" — and accepted him into his program. It was a moment of grace that launched a scientific career spanning four decades.
Beta-Spectroscopy at JINR Dubna
Umarov's nuclear physics work centered on beta-spectroscopy — the precise measurement of electron energies emitted during beta decay. This field was critical to understanding nuclear structure and the fundamental properties of subatomic particles.
In 1957, Umarov organized a group of Uzbek scientists to work at the Joint Institute for Nuclear Research (JINR) in Dubna — the Soviet equivalent of CERN. There, he developed a beta-spectrograph on a permanent magnet, an instrument that allowed precise energy measurements of beta particles without requiring the large electromagnets used in conventional spectrographs. This work would later be documented in the 1970 monograph "Beta-Spectrographs with Permanent Magnets" (with Abdurazzakov and Gromov).
The Landau Debate, 1949
The most dramatic episode in Umarov's nuclear physics career occurred during the defense of his candidate dissertation at Moscow State University in 1949. Among the examiners was Lev Davidovich Landau, one of the greatest theoretical physicists of the twentieth century and a future Nobel laureate.
The dispute centered on the mass of the neutrino — one of the most fundamental questions in particle physics. The prevailing consensus at the time held that the neutrino mass was approximately 0.3 to 0.8 times the electron mass. Umarov's dissertation argued for a dramatically different value: the neutrino mass should be no more than 1/50 to 1/100 of the electron mass — essentially, very close to zero.
Landau disagreed. The debate was fierce. But Umarov held his ground.
"The dissertator remained with his opinion, and the opponent with his."
— Lev Landau, official review of Umarov's dissertation defense, 1949
Despite this standoff with one of the most intimidating intellects in physics, the Moscow State University council voted unanimously — all 43 members — to award Umarov his degree. History would vindicate Umarov's position: modern measurements confirm that neutrino masses are indeed vanishingly small, on the order of fractions of an electron volt — far closer to Umarov's estimate than to the consensus of 1949.
In 1981, the legendary astrophysicist Ya.B. Zeldovich and M.Yu. Khlopov published a landmark paper on cosmological constraints on neutrino mass in Uspekhi Fizicheskikh Nauk, citing Umarov's early work alongside research by 13 Nobel laureates.
The Decision to Return to Tashkent
After his successful defense, Umarov was offered prestigious positions in Moscow. He declined them all. Instead, he chose to return to Tashkent — a decision that puzzled many of his colleagues in the Soviet physics establishment.
His reasoning was both personal and strategic: he wanted to build a scientific community in his homeland, not simply participate in an existing one elsewhere. This decision would prove transformative for Uzbek science.
First Uzbek-Language Physics Education
Back in Tashkent, Umarov became the first scientist to teach advanced physics in the Uzbek language at the Central Asian Polytechnic Institute. Before his initiative, all higher physics education in Uzbekistan was conducted in Russian. By creating Uzbek-language physics curricula, he enabled an entire generation of Uzbek students to learn complex scientific concepts in their native tongue — a foundational act of scientific nation-building.
JINR Dubna, 1957
A decade after his initial training in Leningrad, Umarov organized a delegation of Uzbek physicists to work at the Joint Institute for Nuclear Research in Dubna. This was not merely a research trip; it was a statement that Central Asian scientists belonged at the highest levels of international nuclear research. At JINR, Umarov's team developed instrumentation — particularly the permanent-magnet beta-spectrograph — that represented genuine technical innovation in nuclear measurement science.
The Kurchatov Connection, 1958
In 1958, Umarov organized a plasma physics laboratory at the Physico-Technical Institute in Tashkent, under the direct guidance of Igor Vasilyevich Kurchatov — the father of the Soviet nuclear program and the man who had led the development of the Soviet atomic and hydrogen bombs.
Kurchatov's support was not merely verbal. He sent two full railway wagons of equipment to Tashkent to outfit the new laboratory. This was an extraordinary commitment of resources, signaling the Moscow establishment's confidence in Umarov's ability to build a serious research program far from the traditional centers of Soviet science.
Tokamak Research: The Final Work
Umarov's scientific career came full circle with his final published work: an article on methods of maintaining stable plasma equilibrium in a tokamak. The tokamak — a magnetic confinement device for nuclear fusion — represented the ultimate convergence of his two great scientific passions: nuclear physics and energy.
A tokamak confines superheated plasma in a toroidal magnetic field, seeking the conditions under which hydrogen nuclei can fuse and release energy — the same process that powers the Sun. For a man who had spent decades studying both nuclear reactions and solar energy, the tokamak was the perfect final subject: an attempt to create a miniature sun on Earth.
As his colleagues later wrote: "A man who dreamed of using the power of plasma and the Sun to improve people's lives."