Editing Talk:2186: Dark Matter

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If dark matter were squirrels, they ''wouldn't'' set off the bird feeders because dark matter can't interact with feeders at all!  Especially since it's not to the squirrels' advantage to set them off.  Unless, of course, the dark matter squirrels do exist and steal from our feeders freely, but we can't notice because dark matter is unobservable at this scale.  In fact, it's entirely plausible that some squirrels evolved to be dark matter for this specific advantage, so I wouldn't rule that out.  [[Special:Contributions/172.68.244.174|172.68.244.174]] 12:12, 7 August 
2019 (UTC)
:Well if they can't interact with the feeders, they won't be able to steal the food either.[[Special:Contributions/141.101.107.66|141.101.107.66]] 13:28, 7 August 2019 (UTC)
::Not with that attitude. [[Special:Contributions/162.158.126.4|162.158.126.4]] 14:10, 7 August 2019 (UTC)

I have never seen a spinning bird - can they turn peanuts into gold?
:Yes, but the gold would be radioactive.  The much more impressive reaction is to turn gold into peanuts, other than by paying a farmer for peanuts using the gold.  [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 14:36, 7 August 2019 (UTC)
::Would I be allowed to pay a merchant for peanuts using the gold? --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 14:38, 7 August 2019 (UTC)

I had to google what a spinning bird feeder is. I had never seen one of these before (I live in Germany). Maybe a link to one of these funny videos should be added. Frank [[Special:Contributions/172.68.110.64|172.68.110.64]] 19:59, 7 August 2019 (UTC)
:{{done}} [[Special:Contributions/172.69.22.32|172.69.22.32]] 01:25, 8 August 2019 (UTC)
:You don't have bird feeders in Germany? I know birds exist all around the world, I would think people like to feed them all around the world... Or maybe you're missing squirrels that jump on them and make them spin? [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 04:18, 15 August 2019 (UTC)
::Okay, clicked the link, never heard of that feature before, LOL! I understood just that when they jump on a hanging bird feeder they tend to make it spin, LOL! [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 04:29, 15 August 2019 (UTC)

Anyone else who read PBH as PHB, the pointy haired boss from Dilbert? --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 07:06, 8 August 2019 (UTC)
:I always think "peanut butter and ham," from PBJ+BLT I guess. [[Special:Contributions/172.68.141.148|172.68.141.148]] 07:20, 8 August 2019 (UTC)
:I read it as "Pause Buffered Hitstun". [[User:Probably not Douglas Hofstadter|Probably not Douglas Hofstadter]] ([[User talk:Probably not Douglas Hofstadter|talk]]) 05:17, 11 August 2019 (UTC)


In the explanation, I think I missed a step of logic.  Are Windows, Icons, Mice and Pointers made up of Dark Matter?  It might explain a few lockups in Windows I've been having lately.[[User:Seebert|Seebert]] ([[User talk:Seebert|talk]]) 11:47, 9 August 2019 (UTC)

How can Megan use the dark matter density across the whole solar system to calculate the density within the Earth?  If dark matter interacts with gravity, shouldn't the distribution of dark matter within the Solar system be similar to the distribution of normal matter (i.e. much higher density near massive objects like the Earth)? [[Special:Contributions/108.162.241.124|108.162.241.124]] 17:40, 9 August 2019 (UTC)
:It interacts with gravity, but in doing so it falls into and through ordinary mass and then just keeps going -- gravity isn't strong enough to slow it down enough to make it bunch up around normal matter. Only galaxies have discernible halos clumped. Most dark matter particles that fall into our solar system would just fall out the other side at the same speed, tossing them into the gravity of another star before they slow down enough to come back, in most cases. The linked density paper talks about the extent of that effect as the basis of their calculations. [[Special:Contributions/172.68.141.184|172.68.141.184]] 01:01, 10 August 2019 (UTC)

For comparison, it would be nice to have the average density of "regular" matter of the earth, the sun, interplanetary space, interstellar space, etc. --[[Special:Contributions/141.101.105.246|141.101.105.246]] 18:59, 9 August 2019 (UTC)
:It's a little less than one fifth overall. However, you can't really have a local density of normal matter because it's clumped into stars and planets. Even at our scale, what's underneath is almost certainly far more dense than what's above you. [[Special:Contributions/172.68.141.184|172.68.141.184]] 01:01, 10 August 2019 (UTC)