Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Remembering Louis Nirenberg and his mathematics   The article is dedicated to recalling the life and mathematics of Louis
Nirenberg, a distinguished Canadian mathematician who recently died in New
York, where he lived. An emblematic figure of Analysis and Partial Differential
Equations in the last century, he was awarded the Abel Prize in 2015. From his
watchtower at the Courant Institute in New York, he was for many years a global
teacher and master. He was a good friend of Spain.

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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-th
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The categories of this paper are: chem-ph
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
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The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
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The categories of this paper are: adap-org