English

Random l-colourable structures with a pregeometry

Logic 2017-08-07 v1

Abstract

We study finite ll-colourable structures with an underlying pregeometry. The probability measure that is used corresponds to a process of generating such structures (with a given underlying pregeometry) by which colours are first randomly assigned to all 1-dimensional subspaces and then relationships are assigned in such a way that the colouring conditions are satisfied but apart from this in a random way. We can then ask what the probability is that the resulting structure, where we now forget the specific colouring of the generating process, has a given property. With this measure we get the following results: 1. A zero-one law. 2. The set of sentences with asymptotic probability 1 has an explicit axiomatisation which is presented. 3. There is a formula ξ(x,y)\xi(x,y) (not directly speaking about colours) such that, with asymptotic probability 1, the relation "there is an ll-colouring which assigns the same colour to xx and yy" is defined by ξ(x,y)\xi(x,y). 4. With asymptotic probability 1, an ll-colourable structure has a unique ll-colouring (up to permutation of the colours).

Keywords

Cite

@article{arxiv.1207.4936,
  title  = {Random l-colourable structures with a pregeometry},
  author = {Ove Ahlman and Vera Koponen},
  journal= {arXiv preprint arXiv:1207.4936},
  year   = {2017}
}

Comments

35 pages

R2 v1 2026-06-21T21:39:02.353Z