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Most of the volume of Greenland is ice, you could melt all that and measure it with a cup or bucket? Multiply by density and you're done

I have a really hard time imagining that something with such a small mass can still be dense enough to pull in light. It feels like there shouldn't be enough gravitational pull left in the thing to keep itself that dense

Gravity falls off as the square of the distance, which works in the other direction, too. A blue whale doesn’t have much gravitational attraction (relatively speaking), because on average you’re half a blue whale away from the center of mass. But put all that mass in a single point… 1/

Well, the lower bound isn't yet known, so that may be the case for a mass below 10^5.5 kg (the mass shown in the graph) But otherwise, if you can make a singularity, it's past the point that regular considerations like pressure matter. It'll stay a singularity until it evaporates

Some white cells are constantly being made and dying like most cells and others youre born and die with like female eggcels and neurons, this is because white cell is a generic term for a number of diferent cells in your body that are white big and part of your inmune sistem

I really wonder about the rate of entropy production among all of these. How does life compare to the star lifecycle and black hole evaporation?

Known black holes are so big, and subsequently so cold, that they're taking in more energy from empty space than they eject. IIRC this means their entropy is going up, and will continue to do so for a long time until the universe has expanded enough that the background radiation is cooler

Especially from the point of view that stars radiating their high temperature energy is what drives life to evolve to produce entropy faster

Lifetime >10e30, size 10e-27 — so way off the scale to the left and top! *wikipedia page for “proton” says mean lifetime >10e30, but page for “proton decay” says >10e34, so 🤷. Hella long either way

I saw your profile picture as a recommended follow and felt an ice cold shock of excitement or perhaps terror. I thought to myself that the stick figure man that made XKCD was here? On Bluesky? It was incredible. I'm a little intimidated.

The "briefly exists" part is due to Hawking radiation. The smaller a black hole is, the more it radiates, and it has less mass to radiate away, so tiny black holes have short lifetimes. How you get a black hole that size in the first place is more of an open question.

Start with a slightly bigger one and let it evaporate. How you get one in our current time frame would be an actual conundrum.

Tiny ones evaporate due to hawking radiation really quickly. I think I learned that when people being scared that the LHC would make a black hole was in the news. TL;DR: even if it did, it wouldn't matter.