Difference between revisions of "Talk:2035: Dark Matter Candidates"

Explain xkcd: It's 'cause you're dumb.
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(Response about black hole sizes)
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*10<sup>40</sup> kg the real big black holes with a diameter in the size of our solar system
 
*10<sup>40</sup> kg the real big black holes with a diameter in the size of our solar system
 
Everything except the Buzzkill is below a single solar mass. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 16:24, 20 August 2018 (UTC)
 
Everything except the Buzzkill is below a single solar mass. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 16:24, 20 August 2018 (UTC)
 +
: The theoretical lower limit for black hole mass is the planck mass (22 µg), although such micro black holes would evaporate very quickly under standard models. However, larger black holes were excluded fairly early by gravitational lensing searches ('buzzkill' cases), so smaller black holes had to be considered separately as dark matter candidates. --[[User:Quantum7|Quantum7]] ([[User talk:Quantum7|talk]]) 20:40, 20 August 2018 (UTC)

Revision as of 20:40, 20 August 2018

"thin patina of grime covering the whole universe" is a reference to the "International prototype kilogram" and the necessity to keep it dust-free to preserve its reference status. 108.162.229.100 11:14, 20 August 2018 (UTC)

I think it's just referring to how your room or furniture can get super dirty and completely covered in dust, but you don't really notice it getting dirty because it happens so gradually. But once you actually get around to cleaning your room and you remove all the dust you realize how insanely filthy your room was, now that you can compare it to clean. Since there hasn't been a massive universe cleaning within human history, we wouldn't really be able to tell if the universe was coated in dirt because we wouldn't remember what it looks like clean. Yosho27 (talk) 12:53, 20 August 2018 (UTC)
I concur, my thought upon reading the "thin patina of grime" was when I helped a friend power wash his back deck and we realized it was far more dirty than we thought; as the newly washed sections stood out in stark contrast to the grimy parts.162.158.186.246 19:29, 20 August 2018 (UTC)
109 kg - 1033 kg black holes

Not sure if it's a mistake by Randall or he has something other in mind. But most of his black holes are far too lightweight:

  • 109 kg is a million tons, the Great Pyramid of Giza wights six times of that
  • 6x1024 kg Earth
  • 2x1030 kg Sun
  • 1031 kg smallest known stellar black hole
  • 1040 kg the real big black holes with a diameter in the size of our solar system

Everything except the Buzzkill is below a single solar mass. --Dgbrt (talk) 16:24, 20 August 2018 (UTC)

The theoretical lower limit for black hole mass is the planck mass (22 µg), although such micro black holes would evaporate very quickly under standard models. However, larger black holes were excluded fairly early by gravitational lensing searches ('buzzkill' cases), so smaller black holes had to be considered separately as dark matter candidates. --Quantum7 (talk) 20:40, 20 August 2018 (UTC)