The Skyrme model of nuclear physics requires quantisation if it is to match observed nuclear properties. A simple technique is used to find the normal mode spectrum of the baryon number B=4 Skyrme soliton, representing the α particle. We find sixteen vibrational modes and classify them under the cubic symmetry group O_h of the static solution. The spectrum possesses a remarkable structure, with the lowest energy modes lying in those representations expected from an approximate correspondence

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... ween Skyrmions and BPS monopoles. The next mode up is the 'breather', and above that are higher multipole breathing modes.