3-Nets realizing a diassociative loop in a projective plane

A 3-net of order n is a finite incidence structure consisting of points and three pairwise disjoint classes of lines, each of size n, such that every point incident with two lines from distinct classes is incident with exactly one line from each of the three classes. The current interest around 3-ne...

Teljes leírás

Elmentve itt :
Bibliográfiai részletek
Szerzők: Korchmaros Gábor
Nagy Gábor Péter
Dokumentumtípus: Cikk
Megjelent: 2016
Sorozat:DESIGNS CODES AND CRYPTOGRAPHY 79 No. 3
Tárgyszavak:
doi:10.1007/s10623-016-0176-9

mtmt:3071615
Online Access:http://publicatio.bibl.u-szeged.hu/29126
Leíró adatok
Tartalmi kivonat:A 3-net of order n is a finite incidence structure consisting of points and three pairwise disjoint classes of lines, each of size n, such that every point incident with two lines from distinct classes is incident with exactly one line from each of the three classes. The current interest around 3-nets (embedded) in a projective plane PG(2, K), defined over a field K of characteristic p, arose from algebraic geometry; see Falk and Yuzvinsky (Compos Math 143: 1069-1088, 2007), Miguel and Buzunariz (Graphs Comb 25: 469-488, 2009), Pereira and Yuzvinsky (Adv Math 219: 672-688, 2008), Yuzvinsky (140: 1614-1624, 2004), and Yuzvinsky (137: 1641-1648, 2009). It is not difficult to find 3-nets in PG(2, K) as far as 0 < p <= n. However, only a few infinite families of 3-nets in PG(2, K) are known to exist whenever p = 0, or p > n. Under this condition, the known families are characterized as the only 3-nets in PG(2, K) which can be coordinatized by a group; see Korchmaros et al. (J Algebr Comb 39: 939-966, 2014). In this paper we deal with 3-nets in PG(2, K) which can be coordinatized by a diassociative loop G but not by a group. We prove two structural theorems on G. As a corollary, if G is commutative then every non-trivial element of G has the same order, and G has exponent 2 or 3 where the exponent of a finite diassociative loop is the maximum of the orders of its elements. We also discuss the existence problem for such 3-nets.
Terjedelem/Fizikai jellemzők:443-449
ISSN:0925-1022