Question
This condition is used in the derivation of the Liénard–Wiechert (“l’yay-NARR VEE-curt”) potentials to reduce a degree of freedom in the time-dependent field. For 10 points each:
[10h] Name this condition that sets the four-gradient of the electromagnetic four-potential equal to zero.
ANSWER: Lorenz gauge condition [accept Lorenz gauge fixing; prompt on gauge condition or gauge fixing]
[10e] The Lorenz gauge condition is sometimes used instead of this scientist’s gauge condition because it is Lorentz-invariant. This scientist names an inverse-square force law between charged objects.
ANSWER: Charles-Augustin de Coulomb [accept Coulomb’s law or Coulomb gauge condition]
[10m] The Lorenz gauge allows one to write Maxwell’s equations using the d’Alembertian (“dal-ahm-BARE-shin”), which generalizes this operation to Minkowski space. This operation is the divergence of the gradient and is symbolized “nabla squared.”
ANSWER: Laplacian [or Laplace operator]
<Physics>
Summary
| 2023 ACF Winter @ Columbia | 11/11/2023 | Y | 9 | 13.33 | 89% | 33% | 11% |
Data
| Bard A | Princeton A | 0 | 0 | 0 | 0 |
| Columbia A | Rutgers B | 10 | 10 | 10 | 30 |
| Princeton B | Cornell C | 0 | 10 | 10 | 20 |
| NYU A | Columbia C | 0 | 10 | 0 | 10 |
| Yale A | Penn B | 0 | 10 | 0 | 10 |
| Rowan A | Yale B | 0 | 10 | 0 | 10 |
| Vassar | Yale C | 0 | 10 | 0 | 10 |
| Penn A | Haverford | 0 | 10 | 10 | 20 |
| NYU B | Rutgers A | 0 | 10 | 0 | 10 |