Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: 27 Open Problems in Kolmogorov Complexity   The paper proposes open problems in classical Kolmogorov complexity. Each
problem is presented with background information and thus the article also
surveys some recent studies in the area.

8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph