Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The wave equation for stiff strings and piano tuning   We study the wave equation for a string with stiffness. We solve the equation
and provide a uniqueness theorem with suitable boundary conditions. For a
pinned string we compute the spectrum, which is slightly inharmonic. Therefore,
the widespread scale of 12 equal divisions of the just octave is not the best
choice to tune instruments like the piano. Basing on the theory of dissonance,
we provide a way to tune the piano in order to improve its consonance. A good
solution is obtained by tuning a note and its fifth by minimizing their beats.

19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin