Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The conjugacy problem in automaton groups is not solvable   (Free-abelian)-by-free, self-similar groups generated by finite self-similar
sets of tree automorphisms and having unsolvable conjugacy problem are
constructed. Along the way, orbit undecidable, free subgroups of GL_d(Z), for d
> 5, and Aut(F_d), for d > 4, are constructed as well.

29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex