Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lifetimes of Heavy-Flavour Hadrons -- Whence and Whither?   A theoretical treatment for the weak decays of heavy-flavour hadrons has been
developed that is genuinely based on QCD. Its methodology as it applies to
total lifetimes and the underlying theoretical issues are sketched. Predictions
are compared with present data. One discrepancy emerges: the beauty baryon
lifetime appears to be significantly shorter than expected. The ramifications
of those findings are analyzed in detail.

34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg