Question
Answer the following about changes of angle in special relativity, for 10 points each.
[10e] Explaining the apparent time discrepancy in this thought experiment relies on the fact that one of the two people involved turns through 180 degrees and starts traveling in the opposite direction.
ANSWER: twin paradox
[10h] In this visual distortion effect, objects traveling at relativistic speeds appear to observers at a different angle of perspective, since light from different points on the object takes different times to reach the observer.
ANSWER: Terrell effect [accept Terrell rotation, Penrose–Terrell effect, Terrell–Penrose effect, Lampa–Terrell–Penrose effect, or Lampa–Penrose–Terrell effect]
[10m] When converting between two inertial reference frames, values of this hyperbolic angle can simply be added together. This quantity is equal to artanh (“ar-tanch”) of v over c.
ANSWER: rapidity [or rapidities; reject “rapid”]
<Physics>
Summary
| 2024 ACF Nationals | 2024-04-21 | Y | 21 | 15.71 | 91% | 52% | 14% |
Data
| Chicago D | Waterloo | 0 | 0 | 10 | 10 |
| Chicago C | Claremont Colleges | 10 | 0 | 0 | 10 |
| Columbia A | McGill | 10 | 10 | 10 | 30 |
| Columbia B | North Carolina B | 10 | 0 | 10 | 20 |
| Cornell A | Michigan | 0 | 0 | 10 | 10 |
| Chicago B | Duke | 10 | 0 | 10 | 20 |
| Georgia Tech | Arizona State | 10 | 0 | 0 | 10 |
| Harvard | NYU | 10 | 0 | 0 | 10 |
| Indiana | Toronto A | 10 | 10 | 10 | 30 |
| Iowa State | Florida | 10 | 0 | 0 | 10 |
| Minnesota A | Brown | 10 | 0 | 10 | 20 |
| Berkeley B | North Carolina A | 10 | 0 | 0 | 10 |
| Northwestern | Truman State | 10 | 0 | 0 | 10 |
| Purdue | Maryland | 10 | 0 | 0 | 10 |
| Texas | South Carolina | 10 | 0 | 0 | 10 |
| Berkeley A | Toronto B | 10 | 0 | 10 | 20 |
| Kentucky | Virginia | 10 | 0 | 0 | 10 |
| Johns Hopkins | WUSTL A | 10 | 0 | 10 | 20 |
| Chicago A | WUSTL B | 10 | 10 | 10 | 30 |
| Yale A | Cornell B | 10 | 0 | 10 | 20 |
| Yale B | Stanford | 10 | 0 | 0 | 10 |