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| Side Effect |
 Title text: Brace yourself--the chirp gets pretty weird. |
Explanation
This comic takes the concept of medication side-effects ad absurdum. The side effect of sensitivity to sun exposure described by Beret Guy is entirely precedented; however, heightened sensitivity to gravitational waves is not a known effect.[citation needed] Due to the entirely normal first side effect, Ponytail initially misses the gravitational wave side effect. She is about to find out what that is about.
Gravitational waves are waves of distortion in spacetime caused by fast-moving massive objects, such as neutron stars and/or black holes orbiting each other. The waves travel at the speed of light and can be measured by precise instruments (e.g., interferometers) which detect the ever-so-slight stretching and squishing caused by gravitational waves. As a side-effect of his medication, Beret Guy exhibits the stretching and squishing of a gravitational wave much more strongly than normal, to the degree that it's visible to the naked eye. Beret Guy's hat also stretches and shrinks, indicating it could be a part of his body, which contradicts the idea from an earlier comic that it is stapled to his head. Alternatively, it may be part of the strange power the medicine makes him exhibit.
This is probably the most extreme example to date of Beret Guy's peculiar sensitivity to minuscule external forces. By way of comparison, the most sensitive current ground-based laser interferometer, LIGO, has detection arms which are 4 km in length, and with strong gravitational waves, it experiences changes in the distance between the ends of the arms by at most roughly 10β18 meters, or 1 attometer; for comparison, a proton's diameter is roughly 1700 attometers. The relative change is thus about 2.5 Γ 10-22. If Beret Guy is experiencing distortions of about a quarter of his height, the relative change is 0.25, larger than LIGO's by a factor of about 1021. However, rather than showing concern for his body rapidly changing shape, he instead enjoys the feeling, saying 'Wheee!' in the last panel. This could just be because his whole body 'rides' his own personal changes in space-time geometry, everything down to his molecular bonds extend and contract in proportional synchronisation to all parallel bonds β aside from watching out for non-fluctuating surroundings (like a ceiling suddenly being effectively too low for comfort), the effect applies consistently (unlike in spaghettification, across the gravitational potential from a nearby massive object) his body and all his personally-attuned clothing experiences no great mechanical stress.
The "chirp" described in the title text refers to gravitational waves during the end-stages of the collision of two black holes and/or neutron stars, during which expansion and contraction of the waves sweeps up in frequency to the point where they alternate extremely rapidly. This type of wave is called a chirp in signal analysis. When the gravitational wave is represented as sound, it does indeed make a chirping sound. The chirp would also cause Beret Guy's body to change form repeatedly and rapidly. In the final stages of the merger, the colliding stars emit waves whose period is on the order of a couple of milliseconds, so if Beret Guy's sensitivity to the waves remained constant, a human observer would see only a blur. However, in normal Beret Guy fashion, he somewhat smooths over that strange and concerning affect, describing it only as 'pretty weird' in his warning to Ponytail.
Beret Guy's reaction to the gravitational wave seem similar to a surfer: he says "Here comes one now!", and after it passes him, "Wheee!". Since gravitational waves propagate at the speed of light, normal people can't receive any information from them before they actually arrive, so they can't know that one is coming. But of course Beret Guy can.
Transcript
- [Beret Guy is standing to the right of Ponytail.]
- Beret Guy: This new topical medication makes me extra sensitive to sun exposure and gravitational waves.
- [Beret Guy's arms are out.]
- Ponytail: Oh yeah, that's a common ...wait, what was that last part?
- Beret Guy: Here comes one now!
- [Ponytail stands facing Beret Guy, who is stretched out in height.]
- [Ponytail stands facing Beret Guy, who is now shorter and wider than he was originally.]
- [Ponytail stands facing Beret Guy, who is now stretched out in height again as he was in the third panel.]
- Beret Guy: WHEEE!
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