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Dark Matter Candidates
My theory is that dark matter is actually just a thin patina of grime covering the whole universe, and we don't notice it because we haven't thoroughly cleaned the place in eons.
Title text: My theory is that dark matter is actually just a thin patina of grime covering the whole universe, and we don't notice it because we haven't thoroughly cleaned the place in eons.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Every section needs to be filled and explained. Do NOT delete this tag too soon.

This comic gives a set of possibilities of what dark matter could possibly be. In cosmology, dark matter is an unknown type of matter thought to account for 85% of the total matter in the universe. The joke in this comic is that the range of the mass of the possible particles and objects stretch over 81 powers of ten. Randall filled the gap between small candidate particles and large candidate objects with highly absurd suggestions.

Axion

An hypothetical elementary particle that might be a component of dark matter.


Sterile neutrino

An hypothetical particle interacting only via gravity. It's an actual candidate for dark matter.


Electrons painted with space camouflage


Neutralino

A hypothetical particle from Supersymmetry. It's an actual candidate for dark matter.


Q-ball

In theoretical physics, a Q-ball is a stable group of particles. It's an actual candidate for dark matter.

In billiards, a cue ball is the white (or yellow) ball hit with the cue in normal play.


Pollen A joke candidate, though people with seasonal allergies may suspect that the universe genuinely is made up entirely of pollen in the springtime.


No-See-Ums

Also called Ceratopogonidae, a family of small flies (1–4 mm long) who can pass through most window screens.


8-balls

In billiards, the 8-ball is a black ball numbered 8. It's a pun with Q-ball/cue ball.


Space Cows


Obelisks, Monoliths, Pyramids

While those human constructions are huge on a human scale, they're negligible at universe-scale. They often show up in fiction and pseudo-scientific literature as alien artifacts generating immense unknown power out of nowhere.


Black Holes ruled out by:

  • Gamma Rays
    • If dark matter were black holes of this size, the black holes would be evaporating in bursts of hawking radiation, and we'd see a buzz of gamma rays from every direction.
  • GRB lensing
  • Neutron Star Data
  • Mirco lensing
  • Solar System Stability
  • Buzzkill Astronomers


Maybe those orbit lines on space diagrams are real and very heavy

Any diagram of our solar system (or any solar system) will show lines representing the path the planet takes around its sun. Since planets orbit in ellipses, there will be an ellipse for every planet. This lines don't show real objects, though. Astronomers just draw them on pictures of the solar system to show where the planets move. If you draw a line on a map to give someone directions, that line isn't an object in real life; it's just on the map. If these lines were real, they would be huge (Earth's would be 940 million km long (2*pi*AU) and Neptune's would be 28 BILLION kilometers long). If they were also very dense, they would have a huge mass and could possibly account for the missing 85% of the mass in the universe. But they would also constantly be impaling the inner four planets, including the Earth, which would be a problem. Overall, not a very likely candidate. Yosho27 (talk) 13:04, 20 August 2018 (UTC)

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.

Dark matter candidates:

[A list of candidates on a scale. The scale unit starts with energy and ends with mass:]

Start End Candidate
< µeV 10 meV Axion
eV 10 KeV Sterile neutrino
MeV MeV Electrons painted with space camouflage
10 GeV 10 TeV Neutralino
100 TeV 10^-17 kg Q-ball
ng 100 ng Pollen
mg mg No-See-Ums
10^-1 g 10^-1 g Bees
10 g 100 g 8-balls
100 kg TON Space Cows
TON 10^9 kg Obelisks, Monoliths, Pyramids
10^9 kg 10^33 kg Black Holes ruled out by:
  • Gamma Rays
  • GRB lensing
  • Neutron Star Data
  • Mirco lensing
  • Solar System Stability
  • Buzzkill Astronomers
10^33 kg > 10^36 kg Maybe those oribt lines on space diagrams are real and very heavy



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