Packet 1: Bonus 6

This operator’s components are the prototypical spherical basis in 3-dimensional space. For 10 points each:
[10e] Name this operator whose total amount is conserved in rotationally invariant systems by Noether’s theorem. In quantum physics, this operator is divided into “orbital” and “intrinsic” forms.
ANSWER: angular momentum [accept L or J; accept total angular momentum or orbital angular momentum or intrinsic angular momentum; reject “momentum”]
[10m] Addition of angular momenta is readily done by a basis change from a space where the summands have this property to one where the sum does. Matrices commute if and only if they have the “simultaneous” form of this property.
ANSWER: diagonalizable [or diagonalizability; accept simultaneously diagonalizable; reject “diagonal”]
[10h] For two spin-half particles, the basis change produces a space made by performing this operation to a spin-1 and spin-0 space. A Fock space is made by performing this operation on a sequence of n-particle Hilbert spaces.
ANSWER: direct sum [prompt on sum]
<Editors, Physics> | J. Playoffs 1 (Editors 1)

HeardPPBE %M %H %
2411.2571%29%13%

Back to bonuses