An example of a convex body without symmetric projections

Citation
Ed. Gluskin et al., An example of a convex body without symmetric projections, ISR J MATH, 124, 2001, pp. 267-277
Citations number
13
Categorie Soggetti
Mathematics
Journal title
ISRAEL JOURNAL OF MATHEMATICS
ISSN journal
00212172 → ACNP
Volume
124
Year of publication
2001
Pages
267 - 277
Database
ISI
SICI code
0021-2172(2001)124:<267:AEOACB>2.0.ZU;2-D
Abstract
Many crucial results of the asymptotic theory of symmetric convex bodies we re extended to the non-symmetric case in recent years. That led to the conj ecture that for every n-dimensional convex body K there exists a projection P of rank k, proportional to n, such that PK is almost symmetric. We prove that the conjecture does not hold. More precisely, we construct an n-dimen sional convex body K such that for every k > C rootn ln n and every project ion P of rank k, the body PK is very far from being symmetric. In particula r, our example shows that one cannot expect a formal argument extending the "symmetric" theory to the general case.