Catch up, neutrinos: Nobel Prize in physics given for "ghost messages" from outer space

The Nobel Prize in Physics in 2026 was awarded to Francis Halzen. The award recognized the merits of the scientist who became one of the initiators of the creation of the IceCube neutrino observatory in Antarctica. It consists of thousands of optical sensors frozen in ice. They pick up faint flashes of light that occur during rare interactions of neutrinos with matter. With the help of the installation, scientists, in particular, discovered high-energy neutrinos of astrophysical origin. At the same time, Soviet and Russian experts made a significant contribution to the development of neutrino astronomy, experts interviewed by Izvestia noted. Today, the Baikal-GVD deep-sea telescope plays an important role in studying these particles. In addition, Russia is developing new-generation sensors that can be used for high-precision neutrino detection.

What was the scientist awarded for?

Francis Halzen, a Belgian-born scientist and professor at the University of Wisconsin-Madison (USA), was awarded the Nobel Prize in Physics in 2026. The prestigious award was awarded "for a decisive contribution to the creation of the IceCube neutrino observatory and the discovery of high-energy neutrinos of astrophysical origin," the Nobel Committee announced on Tuesday, October 6.

Halzen proposed using the Antarctic ice sheet as a giant neutrino detector. On his initiative, a three–dimensional network of 5,160 optical sensors was placed at a depth of 1.5-2.5 km. It occupies about a cubic kilometer of ice. The installation was named IceCube Neutrino Observatory. Its construction was completed in 2010.

— Neutrinos almost do not interact with ordinary matter, therefore they are called "ghost particles". Billions of neutrinos fly through every cubic centimeter of space every second, and only very rarely do they participate in the so-called weak interactions. This is one of the four fundamental interactions along with nuclear, electromagnetic, and gravitational interactions," Sergei Yazev, a leading researcher at the Institute of Solar—Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences and director of the Astronomical Observatory of Irkutsk State University, told Izvestia.

He explained that IceCube sensors detect faint flashes of light that appear as a result of rare interactions of neutrinos with matter. Using this radiation, scientists can reconstruct the direction of motion and energy of the particle, and then determine where it came from.

Neutrino sources can be, for example, supernova explosions, processes near black holes, and other powerful astrophysical phenomena. Neutrinos pass through matter almost unhindered, therefore they carry valuable information about processes occurring far beyond the Solar System, noted Sergey Yazev.

— When studying particularly powerful processes in the universe, it is necessary to register particles that can reach us without distorting the direction. In order not to be exposed to the effects of magnetic intergalactic fields, such particles must be neutral, that is, they must not have an electric charge. Therefore, high-energy gamma quanta and neutrinos are suitable for studying distant objects. The IceCube Observatory was the first to register ultrahigh—energy neutrinos," added Semyon Khokhlov, Senior Researcher at the NEVOD Scientific and Educational Center at the Institute of Nuclear Physics and Technology at the National Research Nuclear University MEPhI.

According to Alyona Mastyukova, a researcher at the Russian Quantum Center and secretary of the scientific committee of the National Prize in the Field of Future Technologies "Challenge", Francis Khalzen played a crucial role in the realization of this idea. At the same time, the result was the achievement of a large international team of physicists and engineers. In general, the award highlights the importance of neutrino astronomy for the study of the universe.

— Neutrinos are already helping to solve practically useful problems. For example, installations have been created that are able to monitor the behavior of a nuclear reactor, how fuel is produced, and what happens to it. Such experiments are being conducted in Russia and China. In the future, neutrinos will help to study the structure of the Earth and its core in more detail. In particular, a number of detectors are currently testing the registration of geoneutrinos, particles that are born in the bowels of our planet," explained Yuri Kudenko, chief researcher at the Institute for Nuclear Research and a grantee of the Russian Science Foundation.

The physics of neutrinos is of great importance for fundamental science, the scientist emphasized. For example, studying these particles can help us get closer to answering one of the main mysteries of modern physics — why there is so much more matter in the universe than antimatter. In addition, neutrino detectors are used to search for possible manifestations of dark matter.

What is the role of Russian researchers in the study of neutrinos

As Yuri Kudenko noted, the Nobel Prize for neutrino research can further spur work in this field and the development of new-generation installations, the volume of which will be significantly larger than that of modern detectors. In particular, Russian and Chinese scientists plan to deploy the HUNT neutrino telescope with a volume of up to 30 cubic kilometers in the Baikal area by 2040.

The Baikal-GVD deep-sea neutrino telescope is currently operating in the lake. This is a system of optical modules placed underwater, the total number of which in 2026 approached 4,900. The effective volume of the installation has reached about 0.8 cubic km.

— If we talk about the Baikal neutrino program as a whole, it appeared before IceCube. This is an international collaboration in which Russia plays a major role, but other countries are also involved. The idea of the project appeared in the first half of the 1980s. However, its implementation was greatly slowed down due to the collapse of the Soviet Union and subsequent events. The observatory has been fully operational since about 2018, almost a decade later than IceCube. Nevertheless, the Baikal Neutrino Telescope has also detected a large number of neutrinos," said Dmitry Karlovets, a leading researcher at the New ITMO Physics and Technology Institute.

It is important to understand that Soviet scientists were among the pioneers of the practical development of neutrino astronomy, the researcher added. Neutrino physics has been actively developed in the Soviet Union since the 1950s. One of the important events was the establishment of the Joint Institute for Nuclear Research in Dubna and the work of Italian physicist Bruno Pontecorvo there. He was one of the pioneers of neutrino physics and made a significant contribution to the development of this field.

— Actually, everything is complicated with IceCube. Initially, the idea of registering neutrinos in deep natural reservoirs was proposed by the Soviet theoretical physicist Moses Markov in the 1960s. And in the 1980s, they began to create a prototype of Baikal-GVD. Moreover, even Wikipedia says that Francis Halzen knew about the experiments of Soviet and Russian scientists in Antarctica to register neutrinos. It would be fair to reward a collaboration of scientists with the Nobel Prize, rather than a single researcher," said Evgenia Kravchenko, a senior researcher at MIPT.

According to Yuri Naumov, the author of the NeutrinoHit telegram channel and a leading researcher at the Joint Institute for Nuclear Research, in the 1990s Baikal was the forge of the world's neutrino astronomy cadres. It is enough to recall the German experimental physicist Christian Spearing, a key figure in the history of neutrino astronomy. He participated in the creation of the Russian neutrino telescope, and at the same time joined the American project AMANDA (Antarctic Muon And Neutrino Detector Array)— the predecessor of IceCube.

According to the scientist, among the significant results of the Baikal-GVD project is the registration of an excess of neutrinos with energies above 200 TeV from directions near the plane of our galaxy. This means that it probably has a powerful source of these particles.

Russia is also developing new-generation detectors, said Marina Avilova, Director of the Department of Quantum Technologies at Rosatom State Corporation. In particular, in the program for the development of quantum sensors, which was launched this year, one of the first projects is the creation of thermometers based on superconducting tunneling nanostructures. High-precision neutrino detection and the search for dark matter are among the tasks that these devices will help solve.