Footfalls above "we would see the tracing on the stage floor of a tremendously elongated variation of the figures 8 turned on its side … the mathematical symbol for infinity." Beckett was also indebted to the French psychologist Pierre Janet for his conception of hysterical behaviour. In his overview of Janet's work, Robert Woodworth in his "Contemporary Schools of Psychology", a work Beckett read, pays particular attention to Janet's description of the "hysterical paralysis of one arm", which Beckett incorporated, into May's posture. There are a number of analogies between "Footfalls" and Janet's work with a patient called Irène: He lists
Spin (physics) state and a spin-4 particle should be rotated 90 degrees to bring it back to the same quantum state. The spin-2 particle can be analogous to a straight stick that looks the same even after it is rotated 180 degrees and a spin 0 particle can be imagined as sphere, which looks the same after whatever angle it is turned through. Spin obeys commutation relations analogous to those of the orbital angular momentum: where is the Levi-Civita symbol. It follows (as with angular momentum) that the eigenvectors of and (expressed as kets in the total basis) are: The spin raising