Another example is the idea of wave function collapse. In standard interpretations of quantum physics, a particle is described by a wave function, and attributes such as position or momentum are only discovered through a measurement procedure which collapses the wave function to one of a number of allowed states. In quantum social science, mental states are best described as potentialities that "collapse" only when a judgement or decision is made. One consequence of wave function collapse in physics is that a measurement affects the system being studied, and therefore any future measurement. A corresponding phenomenon in social science is the so-called order effect, where responses to survey questions depends on the order in which they are asked.