Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quasiconvexity, null Lagrangians, and Hardy space integrability under
  constant rank constraints   We present a systematic treatment of the theory of Compensated Compactness
under Murat's constant rank assumption. We give a short proof of a sharp weak
lower semicontinuity result for signed integrands, extending the results of
Fonseca--M\"uller. The null Lagrangians are an important class of signed
integrands, since they are the weakly continuous functions. We show that they
are precisely the compensated compactness quantities with Hardy space
integrability, thus proposing an answer to a question raised by
Coifman-Lions-Meyer-Semmes. Finally we provide an effective way of computing
the null Lagrangians associated with a given operator.

28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an