# Faculty and Researchers

## Mathematics and Physics

An introduction to faculty staff members and laboratories in the Mathematics and Physics.

Note: Information on the laboratories is current as of the 2020 academic year. There may be changes to this information in the 2021 academic year.

#### IKEDA Toru

- Position
- Professor
- Laboratory
- Manifold Laboratory

##### Topology, 3D Manifolds, Knot Theory

A 3-manifold is a space in which a 3D coordinate system can be drawn around arbitrary points. Although it’s difficult to visualize an entire 3-manifold, work here involves cutting and pasting spaces and curves in order to study geometric properties such as symmetry.

#### ISHIBASHI Akihiro

- Position
- Professor
- Laboratory
- General Relativity and Cosmology Laboratory

##### General Relativity, Gravitation, Cosmology

Investigation is conducted into overall space dynamics and black holes using general relativity. A focus of research is on high-dimensional space models and high-dimensional black holes, which look at the possibilities of high-dimensional space-time.

#### INOUE TARO Kaiki

- Position
- Professor
- Laboratory
- Laboratory for Cosmology

##### Cosmology, Astrophysics, Gravitational Astronomy

Dark matter and dark energy are mysterious substances that account for a large portion of the universe. Solutions to these mysterious substances are sought using general relativistic phenomena on cosmic scales such as gravitational lenses, gravitational waves and cosmic inhomogeneity (halos and voids).

#### OHTA Nobuyoshi

- Position
- Professor
- Laboratory
- Elemental Particle and Gravity Theory Laboratory

##### Elemental Particle Theory, Quantum Gravity Theory, Superstring Theory, Cosmology

Studies are carried out on elemental particles, which are smaller than atoms, through the theory of relativity and quantum mechanics, and research is conducted into cosmology and the unified theory of elemental particles, including gravity, through the general theory of relativity and superstring theory.

#### ODA Fumihito

- Position
- Professor
- Laboratory
- Group Theory Laboratory

##### Representation Theory of Finite Groups

Examination is carried out into finite groups and their representation using a category theory approach. Research is conducted into group actions on simplicial complexes, semi-ordered sets, and modules.

#### KATO Yukihiro

- Position
- Professor
- Laboratory
- Experimental Particle Physics Laboratory

##### Experimental Particle Physics

We know that matter is composed of things like quarks and other subatomic particles. But what are subatomic particles composed of? Using a large particle accelerator, research here tries to answer questions like this.

#### KONDO Yasushi

- Position
- Professor
- Laboratory
- Quantum Control Laboratory

##### Quantum Information, Condensed Matter Physics

Research is carried out with an interest in a wide range of control methods, in which quantum mechanics such as quantum information and quantum control play an important role. In particular, if quantum computers are realized, it will change the world. It is hoped that the elemental research conducted here will help make such computers a reality.

#### SAKUMA Kazuhiro

- Position
- Professor
- Laboratory
- Topology Laboratory

##### Topology

I am studying 4D manifolds and the higher dimensional manifolds by using singularity theory of differentiable maps. There appears singular points in general which degenerate for the differential of smooth maps, so we try to observe the method of eliminating singularities with higer coranks.

#### TAKASAKI Kanehisa

- Position
- Professor
- Laboratory
- Integrable Systems Laboratory

##### Algebraic Analysis, Mathematical Physics, Integrable Systems

Solvable models of mathematical physics are referred to as `integrable systems'. I am studying integrable systems and mathematical physics by the method of algebraic analysis. Not only being extremely interesting in themselves, integrable systems are also closely related to many other fields of mathematics.

#### DOTERA Tomonari

- Position
- Professor
- Laboratory
- Soft Matter Physics Laboratory

##### Quasicrystal Physics, Soft Matter Physics, Condensed Matter Physics

This laboratory is the world leader in soft quasicrystal research. This laboratory made the world’s first discovery of a polymeric quasicrystal, implying that even soft matter has an ordered structure with no repetitive units. Theoretical research on the origin of the formation of soft quasicrystals appeared in Nature. Recently Dr. Dotera found the bronze-mean quasicrystal. Also, he aims to develop the science of gyroid.

#### NAKANO Hitoshi

- Position
- Professor
- Laboratory
- Laser Engineering Laboratory

##### Laser Engineering

We are actively conducting research related to laser and electrical energy control, for example, development of new lasers, new functional materials by laser treatment, laser peening, and development of fast high-voltage switch using power semiconductors.

#### HASHISHIN Yuichi

- Position
- Professor
- Laboratory
- Applied Laser Engineering Laboratory

##### Applied Laser Engineering Laser Surgery and Medicine Laser Safety

This laboratory has a wide variety of laser equipment, as well as analyzers and observation systems. We conduct experiments on the use of lasers to cut wood, bone, and meat. We are also doing R&D on practical applications of lasers in the medical and healthcare fields as well as in industry.

#### YOSHIDA Minoru

- Position
- Professor
- Laboratory
- Fiber Optics Laboratory

##### Optical Fibers, Fiber Lasers, Laser Engineering

This lab does research on the fundamentals and potential applications of light, revolving not only around optical communications, but also the development of new lasers that use optical fibers. We also promote development of new optical technologies and enjoy discovering previously unknown phenomena involving light.

#### WAKABAYASHI Tomonari

- Position
- Professor
- Laboratory
- Molecular Physics and Quantum Chemistry

##### Physical Chemistry and Chemistry of Nanostructures

Laser ablated polyenes and fullerenes are studied by molecular spectroscopy and quantum chemistry. With experimental and theoretical knowledges on stability and structures of carbon molecules, microscopic views of high-temperature molecular processes are discussed.

#### ASAI Tsunenobu

- Position
- Associate Professor
- Laboratory
- Combinatorics Laboratory

##### Finite Group Theory

Research is conducted into finite groups and combinatorial structures constructed from groups.

#### ARITOMO Yoshihiro

- Position
- Associate Professor
- Laboratory
- Laboratory of Nuclear Reaction Energy

##### Nuclear Engineering, Nuclear Reaction Theory, Synthesis of Super-Heavy Elements

Under the theme of utilizing energy from nuclear reactions, we have taken up the challenge of elucidating the dynamics of nuclear reactions. We are engaged in wide-ranging research on nuclear fusion and fission, transmutation, reprocessing, and synthesis of super-heavy elements.

#### KASAMATSU Kenichi

- Position
- Associate Professor
- Laboratory
- Laboratory of Theoretical Condensed Matter Physics

##### Theory of Condensed Matter Physics

A Bose gas of neutral atoms cooled down to near absolute zero temperature causes a phase transition called Bose-Einstein condensation, resulting in quantum condensates possessing strange properties, as exemplified by superfluidity. We investigate various phenomena exhibited by atomic Bose-Einstein condensates.

#### SHUTOH Nobumichi

- Position
- Associate Professor
- Laboratory
- Statistical Analysis Laboratory

##### Multivariate analysis, Statistical asymptotic theory

We study the distribution theory for the statistics based on missing data and high-dimensional data. By using the obtained results, we try to improve the existing statistical procedures.

#### SUZUKI Takao

- Position
- Associate Professor
- Laboratory
- Special Functions Laboratory

##### Special functions and Integrable systems

My research field is the theory of special functions which are defined by differential or difference equations in complex domains. These special functions are related to various fields of pure mathematics and applied mathematics. Therefore they are very interesting research object.

#### TAKEMURA Yuichiro

- Position
- Associate Professor
- Laboratory
- Plasma Engineering Laboratory

##### Plasma Engineering

Plasma is variously employed in, for example, plasma TVs and welding, and it has become an absolutely essential industrial technology. We are making practical application of this plasma and conducting research to find uses for it in a variety of other fields.

#### TAKEMOTO Yasuhiko

- Position
- Associate Professor
- Laboratory
- Industrial Management Engineering

##### Industrial Management Engineering, Quality Management, Operational Research, Applied Statistics

Industrial Management is a activity of achieving efficiency, rationalization, and optimization in production systems. This laboratory researches and develops some methods of Industrial Management based on data science and ICT.

#### TANAKA Senku

- Position
- Associate Professor
- Laboratory
- Organic Electronics Laboratory

##### Organic Electronics, Organic Solar Cells

Our main target is a new electronic device with organic semiconductors. Especially, we are focusing on the development of organic solar cells.

#### DANSHITA Ippei

- Position
- Associate Professor
- Laboratory
- Quantum Many-Body Physics Laboratory

##### Theory of condensed matter physics, Theory of atomic, molecular, and optical physics, Theory of quantum control

In condensed matter systems, such as electrons in solids and liquid helium, competitions and/or collaborations of quantum nature and interparticle interactions lead to various interesting phenomena, including superfluidity, superconductivity, quantum phase transitions, and many-body localization. We develop theoretical methods describing quantum many-body systems, aiming to discover novel quantum many-body effects.

#### CHINEN Koji

- Position
- Associate Professor
- Laboratory
- Applicable Algebra Laboratory

##### Analytic Number Theory, Coding Theory

Coding theory is about ways to properly relay information. It is a comprehensive theory that is the result of numerous mathematical developments. Research is conducted with a focus on algebra, including coding theory as a mathematical theory and related group theory, and ring theory. Research is also conducted into analytic number theory as it relates to ciphers.

#### NAKAMURA Yayoi

- Position
- Associate Professor
- Laboratory
- Computational Algebraic Analysis Laboratory

##### Computational Algebraic Analysis

By the usage of residues, multiple polylogarithms and multiple zeta values are studied.

#### NISHIYAMA Masayoshi

- Position
- Associate Professor
- Laboratory
- Laboratory for Dynamic Living Systems

##### Biophysics, Bioimaging

Biomolecules are nanometer-sized molecular machines working in living cells. Our research goal is to elucidate the operating principle how biological molecular machines work efficiently in collaboration with water molecules.

#### HOHARA Shinya

- Position
- Associate Professor

##### Radiation Measurement

#### MASUI Takahiko

- Position
- Associate Professor
- Laboratory
- Solid State Physics Laboratory

##### Condensed Matter Physics (experiments)

In the field of condensed matter physics, it’s possible to conduct research by creating one’s own specimens and measuring these. It is interesting in a completely different way than mega science. The goal here is to discover new physical phenomena and new matter, as well as solve long-debated mysteries of science.

#### MATSUI Yutaka

- Position
- Associate Professor
- Laboratory
- Microlocal Analysis Laboratory

##### Mathematics, Algebraic Analysis, Microlocal Analysis

The field of specialty here is algebraic analysis, which grew out of research into differential equations. Using combinatorics and microlocal analysis, research is conducted into reversion formulas of radon transforms of constructible functions, and the behavior of images.

#### MATSUMOTO Yoshiyuki

- Position
- Associate Professor
- Laboratory
- Electric Physical Properties Laboratory

##### Hydrogen-Bonded Ferroelectrics, Superionic Conductors

The physical properties of many materials having hydrogen bonds undergo a variety of changes when conditions change. To answer the question of why such changes occur, we irradiate substances with lasers and measure the frequency of the scattered light.

#### YANO Yohko

- Position
- Associate Professor
- Laboratory
- Biophysics Laboratory

##### Biophysics, Chemical Physics, Structural Chemistry

Protein comes in various complex structures in the body in order to perform its functions. On the other hand, it easily changes form and loses its functions. These structural changes are observed using the world’s brightest X-rays in order to understand the mechanisms behind the formation of protein structures.

#### YAMASHITA Tomoki

- Position
- Associate Professor
- Laboratory
- Discrete Mathematics Laboratory

##### Graph Theory

Most discrete structures can be expressed in graph form. Graph theory represents a major research field of discrete mathematics. Here, research is conducted into extremal graph theory, which is the relationship between invariants and local substructures of the graph.

#### OMURA Yuji

- Position
- Lecturer
- Laboratory
- Theoretical Particle Physics Laboratory

##### Theoretical Particle Physics

We study a lot of new physics possibilities motivated by mysteries in our universe and discuss which models are realistic to explain the latest experimental results. We explore for unknown physics beyond the Standard Model of elementary particle.

#### In Dae JONG

- Position
- Lecturer
- Laboratory
- Knot Theory Laboratory

##### Knot Theory

Research is conducted into knot theory and low-dimension topology (3D and 4D). To investigate knots mathematically, often the invariants of knots are used. Research takes an interest in the relation between the algebraic properties of invariants and the geometrical properties of knots.

#### NOBUKAWA Kumiko

- Position
- Lecturer
- Laboratory
- High-energy Astrophysics Lab.

##### High-energy Astrophysics

X-ray observations have revealed that the universe is hot and energetic. My research focuses on high-energy phenomena occurring in our galaxy. I am also developing the CCD detector onboard the XRISM satellite.

#### YOSHIDA Shuhei

- Position
- Lecturer
- Laboratory
- Photonics Engineering Laboratory

##### Optical Engineering, Holography, Information Storage Engineering

We are addressing research and development on measurement, display, visualization, and information storage technologies based on holography.

#### ANTON Timur Jaelani

- Position
- Researcher
- Laboratory
- Laboratory for Cosmology

##### Observational cosmology, Astrophysics, Gravitational lensing

Strong gravitational lenses are valuable phenomena for studying astrophysics and cosmology. Lensing is a unique probe of the (dark) matter distribution at large-scale and also can act as a natural telescope that magnifies the background sources, allowing for detailed studies of their properties at high resolution. This phenomena appear as a unique probe of the dark matter structure of galaxies, groups, and clusters, as well as an independent tool for constraining cosmological parameters.

#### GOTO Shimpei

- Position
- Researcher
- Laboratory
- Quantum Many-Body Physics Laboratory

##### Theory of condensed matter physics, Numerical simulations, Tensor networks

#### HIGUCHI Yuichi

- Position
- Researcher
- Laboratory
- Laboratory for Cosmology

##### Cosmology, Astrophysics

The universe is mainly composed of unknown "dark matter" and "dark energy". Their nature have not been understood. Investigating the nature is important to understand the universe and test the Einstein's theory of general relativity. We will investigate the nature by carrying out gravitational lensing analysis of simulations and multi-wavelength data.