Researcher Information



Challenge the mystery of the universe and the world of elementary particles

Department of Physics, Nonlinear Physics

Fieldparticle physics, cosmology
Keywordsuperstring theory, standard model of particle physics, cosmology, compact space

Introduction of Research

Superstring theory is a good candidate for a unified theory of all interactions including gravity, and quarks and leptons as well as the Higgs particle. We study particle physics and cosmology, which can derived from superstring thoery. Superstring thoery predicts six-dimensional space, which must be compact, in addition to our four-dimensional spacetime. Geometrical aspects of compact space determine which type of paticle appears and theri properties. We study superstring theory on compact space, which realizes our world and derive their predictions.

Representative Achievements

Y.Katsuki, Y.Kawamura, T.Kobayashi, N.Ohtsubo, Y.Ono and K.Tanioka,
''Z(n) Orbifold Models,''
Nucl. Phys. B 341, 611 (1990).
T.Kobayashi, S.Raby and R.J.Zhang,
''Searching for realistic 4d string models with a Pati-Salam symmetry: Orbifold grand unified theories from heterotic string compactification on a Z(6) orbifold,''
Nucl. Phys. B 704, 3 (2005)
K.Choi, K.S.Jeong, T.Kobayashi and K.i.Okumura,
''Little SUSY hierarchy in mixed modulus-anomaly mediation,''
Phys. Lett. B 633, 355 (2006)
T.Kobayashi, H.P.Nilles, F.Ploger, S.Raby and M.Ratz,
''Stringy origin of non-Abelian discrete flavor symmetries,''
Nucl. Phys. B 768, 135 (2007)
H.Ishimori, T.Kobayashi, H.Ohki, Y.Shimizu, H.Okada and M.Tanimoto,
''Non-Abelian Discrete Symmetries in Particle Physics,''
Prog. Theor. Phys. Suppl. 183, 1 (2010)