Question

This interaction in “hard” and “soft” parts of a bilayer enables data recording in a namesake type of “spring media.” DiVincenzo et al. showed that terms modeling this interaction can represent any quantum computation. This finite-range interaction contributes to the formation of Peierls (“PIE-urls”) droplets. The Goodenough (“good-enough”)–Kanamori rules (10[2])concern a “super” variant of (10[1])this interaction that was used to model high-temperature superconductors by Philip Anderson. This interaction’s strength is represented by negative J times a sum of “sigma-i times sigma-j” (-5[1])terms, (-5[2])which gives rise to complex behavior (-5[1])in the Ising (“icing”) model. (-5[1])In the absence (-5[2])of an external field, (-5[1])this interaction dominates below the Curie (-5[1])temperature, (-5[5])encouraging (-5[1])local alignment between magnetic moments. (-5[2])For 10 points, ferromagnetism (-5[1])is often (-5[1])modeled in terms of what interaction between nearby spins? (0[1]) (10[1]0[17])■END■

ANSWER: exchange interaction [or exchange force; accept superexchange interaction; accept exchange spring media; accept Heisenberg interaction; prompt on spin–spin interaction until “spins” is read]
<Physics>
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Summary

TournamentEditionExact Match?TUHConv. %Power %Neg %Average Buzz
2024 ACF Nationals04/21/2024Y2417%0%79%67.00