2 citations · 4 across the 5 of their papers we have counts for
5 papers
A proof of Kobayashi's properness criterion from a viewpoint of metric geometry
Kento Ogawa, Takayuki Okuda
Let be a locally-compact group and a pair of closed subgroups of . For the cases where is a real linear reductive Lie group, T. Kobayashi [Math. Ann. '89, J. Lie…
Functoriality of Bose-Mesner algebras and profinite association schemes
Makoto Matsumoto, Kento Ogawa, Takayuki Okuda
We show that taking the set of primitive idempotents of commutative association schemes is a functor from the category of commutative association schemes with surjective morphisms…
Abundance of nilpotent orbits in real semisimple Lie algebras
Takayuki Okuda
We formulate and prove that there are "abundant" in nilpotent orbits in real semisimple Lie algebras, in the following sense. If S denotes the collection of hyperbolic elements cor…
Tight maps and holomorphicity, exceptional spaces
Oskar Hamlet, Takayuki Okuda
We show that there are no tight nonholomorphic maps from irreducible domains into exceptional codomains, the only exception being the already known tight nonholomorphic maps from t…
Nonexistence of tight spherical design of harmonic index 4
Takayuki Okuda, Wei-Hsuan Yu
We give a new upper bound of the cardinality of a set of equiangular lines in with a fixed angle for each satisfying certain conditions. Our techniques are based…