## Drums that sound the same

###
S. J. Chapman

Recently, an example was given by Gordon et al. of two
drums that
vibrate at exactly the same frequencies. The proof of this fact
consists of mapping each
resonance of the first drum onto a resonance of the second
drum, and vice versa.
Here we give an interpretation of this map in terms of
paper folding
which will allow us to generate many new isospectral drums, including
a simple example in which the frequencies of vibration can be
calculated explicitly.