Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A priori estimates for a relativistic liquid with free surface boundary   We prove energy estimates for a relativistic free liquid body with
sufficiently small fluid velocity in a general Einstein spacetime. These
estimates control Sobolev norms of the fluid velocity and enthalpy in the
interior as well as Sobolev norms of the second fundamental form on the
boundary.

22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org