Abstract :
Neutron stars, usually observed as pulsars, are famous for their very stable rotation and the accuracy with which we can predict their spin frequency. Nonetheless, many isolated pulsars, especially young ones, often display rotational 'glitches' : sudden episodes of spin-up, typically followed by long relaxations of their spin and spin-down rate. Glitches provide a glimpse into the interior dynamics of neutron stars and the physics of the neutron superfluid that resides in their crusts and cores. I will discuss the observational phenomenology of pulsar rotation and the information we can extract about the state of matter in the extraordinary context of the dense star's interior.
