### Abstract

If an isometric embedding l_{p} ^{m} →l_{q} ^{n} with finite p, q>1 exists, then p=2 and q is an even integer. Under these conditions such an embedding exists if and only if n≥N(m, q) where {Mathematical expression} To construct some concrete embeddings, one can use orbits of orthogonal representations of finite groups. This yields:N(2, q)=q/2+1 (by regular (q+2)-gon), N(3, 4)=6 (by icosahedron), N(3, 6)≥11 (by octahedron), etc. Another approach is based on relations between embeddings, Euclidean or spherical designs and cubature formulas. This allows us to sharpen the above lower bound for N(m, q) and obtain a series of concrete values, e.g. N(3, 8)=16 and N(7, 4)=28. In the cases (m, n, q)=(3, 6, 10) and (3, 8, 15) some ε-embeddings with ε ∼ 0.03 are constructed by the orbit method. The rigidness of spherical designs in Bannai's sense and a similar property for the embeddings are considered, and a conjecture of [7] is proved for any fixed (m, n, q).

Original language | English (US) |
---|---|

Pages (from-to) | 327-362 |

Number of pages | 36 |

Journal | Geometriae Dedicata |

Volume | 47 |

Issue number | 3 |

DOIs | |

State | Published - Sep 1 1993 |

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### All Science Journal Classification (ASJC) codes

- Geometry and Topology

### Cite this

*Geometriae Dedicata*,

*47*(3), 327-362. https://doi.org/10.1007/BF01263664

}

*Geometriae Dedicata*, vol. 47, no. 3, pp. 327-362. https://doi.org/10.1007/BF01263664

**Isometric embed-dings between classical Banach spaces, cubature formulas, and spherical designs.** / Lyubich, Yuri I.; Vaserstein, Leonid N.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Isometric embed-dings between classical Banach spaces, cubature formulas, and spherical designs

AU - Lyubich, Yuri I.

AU - Vaserstein, Leonid N.

PY - 1993/9/1

Y1 - 1993/9/1

N2 - If an isometric embedding lp m →lq n with finite p, q>1 exists, then p=2 and q is an even integer. Under these conditions such an embedding exists if and only if n≥N(m, q) where {Mathematical expression} To construct some concrete embeddings, one can use orbits of orthogonal representations of finite groups. This yields:N(2, q)=q/2+1 (by regular (q+2)-gon), N(3, 4)=6 (by icosahedron), N(3, 6)≥11 (by octahedron), etc. Another approach is based on relations between embeddings, Euclidean or spherical designs and cubature formulas. This allows us to sharpen the above lower bound for N(m, q) and obtain a series of concrete values, e.g. N(3, 8)=16 and N(7, 4)=28. In the cases (m, n, q)=(3, 6, 10) and (3, 8, 15) some ε-embeddings with ε ∼ 0.03 are constructed by the orbit method. The rigidness of spherical designs in Bannai's sense and a similar property for the embeddings are considered, and a conjecture of [7] is proved for any fixed (m, n, q).

AB - If an isometric embedding lp m →lq n with finite p, q>1 exists, then p=2 and q is an even integer. Under these conditions such an embedding exists if and only if n≥N(m, q) where {Mathematical expression} To construct some concrete embeddings, one can use orbits of orthogonal representations of finite groups. This yields:N(2, q)=q/2+1 (by regular (q+2)-gon), N(3, 4)=6 (by icosahedron), N(3, 6)≥11 (by octahedron), etc. Another approach is based on relations between embeddings, Euclidean or spherical designs and cubature formulas. This allows us to sharpen the above lower bound for N(m, q) and obtain a series of concrete values, e.g. N(3, 8)=16 and N(7, 4)=28. In the cases (m, n, q)=(3, 6, 10) and (3, 8, 15) some ε-embeddings with ε ∼ 0.03 are constructed by the orbit method. The rigidness of spherical designs in Bannai's sense and a similar property for the embeddings are considered, and a conjecture of [7] is proved for any fixed (m, n, q).

UR - http://www.scopus.com/inward/record.url?scp=0040202600&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0040202600&partnerID=8YFLogxK

U2 - 10.1007/BF01263664

DO - 10.1007/BF01263664

M3 - Article

AN - SCOPUS:0040202600

VL - 47

SP - 327

EP - 362

JO - Geometriae Dedicata

JF - Geometriae Dedicata

SN - 0046-5755

IS - 3

ER -