About Us
Particle Physics (High Energy Physics)
The goal of particle physics is to study the properties of elementary particles and their interactions. These particles are the essential ingredients of our world, and we would like to better understand our Universe by studying them. We focus on theoretical studies of those elementary particles to achieve that goal. Additionally, we work with experimental colleagues to test our theoretical ideas and to develop new theories based on experimental results. Our group has three focus areas,
- Astroparticle physics and the extensions of Einstein’s General Theory of Relativity
- Flavor physics phenomenology related to flavor anomalies and neutrino physics
- Lattice quantum chromodynamics and high-performance computing.
What are elementary particles?
An elementary particle is a particle that has no substructure and cannot be decomposed into other particles.
The entire Universe is considered to consist of elementary particles, and their properties determine the nature of matter.
The study of elementary particles has a long history with theoretical models changing in time.
The currently accepted explanation is called the Standard Model (SM) that consists of the elementary particles quarks, leptons, and bosons.
All the known elementary particles are summarized in the figure below.
The theories contained in the Standard Model are capable of explaining almost all experimental observations. However, although the SM has been highly successful, there are open questions.
- Cosmological observations suggest the existence of dark energy and dark matter in the Universe, which are not included the Standard Model.
- Einstein’s General Theory of Relativity is incompatible with the Standard Model and no theory for quantum gravity has been agreed upon.
- Long-standing anomalies in flavor physics experiments point to the existence physics beyond the Standard Model.
- Experimental confirmation of neutrino flavor oscillations require additional particle content to be included in the Standard Model.
Therefore, physicists do not regard the Standard Model as a final fundamental theory, and would like to determine the origin of the structure of the Standard Model.
Hadron Physics
Individual Research Interests
- Chiho Nonaka
- Theoretical hadronic physics
- Tomohiro Inagaki
- Astroparticle Physics and General Theory of Relativity
- Takuya Morozumi
- Particle flavor physics and neutrino phenomenology
- Ken-Ichi Ishikawa
- Lattice quantum chromodynamics and high-performance computing
- Yusuke Shimizu
- Neutrino phenomenology and flavor physics theory