Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chronological null complete spacetimes admit a global time   The result "chronological spacetimes without lightlike lines are stably
causal" is announced and motivated. It implies that chronological spacetimes
which are null geodesically complete and satisfy the null genericity and the
null (averaged) energy condition admit a time function.

12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess