Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Isotropic-nematic behaviour of hard rigid rods: a percolation theoretic
  approach   Needles at different orientations are placed in an i.i.d. manner at points of
a Poisson point process on $\mathbb R^2$ of density $\lambda$. Needles at the
same direction have the same length, while needles at different directions
maybe of different lengths. We study the geometry of a finite cluster when
needles have only two possible orientations and when needles have only three
possible orientations. In both these cases the asymptotic shape of the finite
cluster as $\lambda \to \infty$ is shown to consists of needles only in two
directions. In the two orientations case the shape does not depend on the
orientation but just on the i.i.d. structure of the orientations, while in the
three orientations case the shape depend on all the parameters, i.e. the i.i.d.
structure of the orientations, the lengths and the orientations of the needles.

21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph