Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Tiny black holes may be exploding stars across the Milky Way

sciencedaily.com

Post reply on HN
Print view View original

31–40 of 106 posts

Re: Tiny black holes may be exploding stars across the Milky Way

#31

Post by kbelder »

mynegation wrote: post #16
ben_w wrote: post #11

Earlier quoted context omitted.

The bad news is that if a black hole is not primordial, the minimum mass is high enough (2-4 M_sol) that it doesn't so much "pass through our system" as "we pass through its". I'm not 100% confident, but rough approximation suggests that a close approach of even 5 AU even at typical interstellar velocities might have an unplesant climate impact by increasing the eccentricity of our orbit.

Did you mean 5 AU or 5 ly? 5 AU at 2-4 M sol intuitively seems like a complete and utter havoc.

At 5 AU, gravitational force would be 1/25 or 4% the strength of the sun at 1 AU. If the black hole was four solar masses, it would exert a pull about 16% as strong as the sun. Probably not enough to rip us out of orbit, but enough to seriously perturb it. I think it's at least an end-of-civilization event.

5 AU is the perfect distance to really wreck Jupiter, though.

Re: Tiny black holes may be exploding stars across the Milky Way

#32

Post by bpodgursky »

9dev wrote: post #17
Schlagbohrer wrote: post #10

3-Body-Problem once again vindicated as the scariest possible explanation for the Fermi Paradox

Many physicists have pointed out several flaws in the dark forest theory, which makes for a great read but doesn’t really carry over to the real universe 1:1.

Why would physicists have anything useful to say about this theory?

Re: Tiny black holes may be exploding stars across the Milky Way

#33

Post by 14u2c »

ben_w wrote: post #11
trollbridge wrote: post #4

Earlier quoted context omitted.

The good news about black holes is that even if one transited the solar system, it would be extremely unlikely to come anywhere near earth.

The bad news is that if a black hole is not primordial, the minimum mass is high enough (2-4 M_sol) that it doesn't so much "pass through our system" as "we pass through its". I'm not 100% confident, but rough approximation suggests that a close approach of even 5 AU even at typical interstellar velocities might have an unplesant climate impact by increasing the eccentricity of our orbit.

5AU seems incredibly close. That's inside the orbit of jupiter. How would it not destabilize the entire system?

Re: Tiny black holes may be exploding stars across the Milky Way

#35

Post by WarmWash »

alansaber wrote: post #28
echelon wrote: post #25

Earlier quoted context omitted.

I think a fragile world hypothesis is more interesting and scary. Instead of a superintelligence killing any emerging intelligence, superintelligence is so smart that it can perturb spacetime in ways that easily kill itself. Kind of like the idea that LLMs will give anyone with a garage the ability to create killer viruses (wild claim), a superintelligence might trivially create black holes that engulf it. If the int…

Sounds logical to me. It's already remarkable that we haven't done this with fission weapons. It's not unreasonable to assume that within a century we'll have antimatter weapons. Destructive potential only goes up.

Every year the IQ needed to destroy the world drops by 1 point.

Re: Tiny black holes may be exploding stars across the Milky Way

#36

Post by ttul »

choboswaggings wrote: post #26

Kind of chilling to think about these tiny black holes. If they have enough gravitational pull to destabilize a white dwarf, I don't want to know what they'd do to our solar system.

These supernova-generating black holes are atomic scale (Schwartzchild radius of 15pm to 15nm), yet they carry the momentum of a large asteroid. If one of these hit the earth, they would cause a life-ending apocalypse like the event that ended the dinosaurs. The fact that this has not happened yet is encouraging.

Re: Tiny black holes may be exploding stars across the Milky Way

#40

Post by 59percentmore »

bpodgursky wrote: post #32
9dev wrote: post #17

Earlier quoted context omitted.

Many physicists have pointed out several flaws in the dark forest theory, which makes for a great read but doesn’t really carry over to the real universe 1:1.

Why would physicists have anything useful to say about this theory?

Because environment makes culture and physics are the environment at relativistic speeds and cosmic distances.
Post reply on HN