4 papers
math.FA2007
Upper bound for isometric embeddings \ell_2^m\to\ell_p^n
Yuri I. Lyubich
The isometric embeddings (, ) over a field are considered, and an upper bound for the minimal is proved. In the…
math.FA2007
Axiomatic theory of divergent series and cohomological equations
Yuri I. Lyubich
A general theory of summation of divergent series based on the Hardy-Kolmogorov axioms is developed. A class of functional series is investigated by means of ergodic theory. The re…
math.CO2007
Lower bounds for projective designs, cubature formulas and related isometric embeddings
Yuri Lyubich
Yudin's lower bound for the spherical designs is generalized to the cubature formulas on the projective spaces over a field K, where K can be R, C, or H (the field of quaternions),…
math.CO2007
On tight projective designs
Yuri I. Lyubich
It is shown that among all tight designs in FP^n, where F is R, C, or H (quaternions), other than RP^1, only 5-designs in CP^1 have irrational angle set. This is the only case of e…