When Professor Kunio Inoue was a high school student, he developed a passion for mathematics. "It is very beautiful," he says. "It has exact answers."
Professor Kunio Inoue
Inoue is now one of the world's leading physicists, specializing in the field of experimental particle physics. He is the Director of Tohoku University's 虎扑电竞 Center for Neutrino Science, and is also Principal Investigator of the Kavli Institute for the Physics and Mathematics of the Universe, at the University of Tokyo.
The subatomic particles known as neutrinos are the focus of Professor Inoue's research. Neutrinos weakly interact and are electrically neutral, making them difficult to capture.
"Neutrinos were theoretically predicted in 1930 and discovered in 1956," notes Inoue. "There are 10 billion times as many neutrinos as other particles in the universe. Understanding the properties of neutrinos is understanding the universe."
In 1998, Inoue was awarded the prestigious Asahi Prize for making the crucial discovery that neutrinos have mass. But there are still many unanswered questions about neutrinos.
Inoue and his colleagues are studying the properties of neutrinos using the KamLAND (Kamioka Liquid-scintillator Anti-Neutrino Detector). KamLAND is located 1,000 meters deep in the Kamioka mine in the mountains of Japan's Gifu Prefecture, and its 1,000-ton liquid scintillator is the world's biggest antineutrino detector.
Section of nylon balloon from liquid scintillator
The research team uses the KamLAND detector to study the behavior of anti-neutrinos by capturing those produced by nuclear power plants in the surrounding region, those produced in the Earth's interior and those emitted by the sun. The goals are to understand how the universe began, the workings of stars like the sun, how stars collapse and the composition of the Earth's interior.
If neutrinos are created, anti-neutrinos are also created -- an example of how the universe tries to maintain a balance. But scientists are still not sure whether neutrinos can be their own antiparticles (the "Majorana" theory) or not (the "Dirac" theory).
Inoue is now trying to determine which theory is correct. He's doing that by conducting a unique search for what physicists refer to as neutrino-less double-beta decay. 'Beta' in this context refers to the high-energy, high-velocity electrons or positrons that