Title text:
In addition to gravity, burritos interact through the strong, weak, and electromagnetic forces, which is believed to be a major contributor to their popularity.
Transcript:
[Cueball and Ponytail are standing in front of a pentacle with lit candles at the corners. A black sphere, the oracle, is floating above the middle of the pentacle.]
Ponytail: Dear oracle,
Ponytail: What is the nature of dark matter?
Oracle: It’s about 20 pounds.[Close up of oracle]
Off-panel: What?
Oracle: Dark matter is a particle. It weighs about 20 pounds.
Oracle: It only interacts through gravity.[Same view as first panel]
Cueball: Only gravity, huh?
Cueball: So none of our experiments are really going to tell us any more about it, then.
Oracle: Afraid not.[Same view as first and third panels, except Cueball lifted his forearm.]
Cueball: So what do we do?
Oracle: You should go out for burritos.
Ponytail: How will that help?
Oracle: Well
Oracle: Burritos are pretty good.
Source: https://xkcd.com/3085/
If a particle really only interacted with gravity, would it pass through matter? AFAIK “touching” things is electron repulsion…
Looking at it from a quantum field perspective, pretty much. If the only interactions are through gravity then the underlying field’s evolution can’t be influenced by anything else, I have no real idea what the implications of that would be because we don’t have a QFT for gravity.