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Tiny black holes may be exploding stars across the Milky Way

sciencedaily.com

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

#41

Post by bell-cot »

kbelder wrote: post #31
mynegation wrote: post #16

Earlier quoted context omitted.

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.

Not an astrophysicist, but I'm thinking 5 AU could quickly fry the Earth - because it takes very little in the way of solar comets, asteroids, and dust to build a temporary accretion disk around such a black hole. That disk might have a temperature of >1M degrees. Plus the dynamo effects of the disk's interactions with the solar magnetic field? Yeah. 5 ly sounds much safer.

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

#43

Post by ungovernableCat »

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.

PBH (if they exist) are microscopic in size. If they're real and qualify as a potential dark matter candidate they have passed our solar system many times with the only thing happening being undetectable gravitational tugs.

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

#44

Post by 98codes »

trollbridge wrote: post #4
empath75 wrote: post #2

This is one of those headlines where I simultaneously think "cool" and now have a new source of low-grade background anxiety about. It can have a seat next to false vacuum collapse.

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.

> extremely unlikely

But never zero.

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

#45

Post by istjohn »

criddell wrote: post #13
Schlagbohrer wrote: post #10

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

Did you intend to say dark forest hypothesis ?

According to physicist Sean Carroll, "hypothesis" and "theory" are interchangeable as the words are used by practicing scientists.

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

#46

Post by andrewflnr »

echelon wrote: post #25
Schlagbohrer wrote: post #10

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

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…

Leaving aside the fact that there's no evidence superintelligence is even possible, no amount of intelligence alone will let you "trivially" create black holes. Creating black holes requires a ludicrous amount of energy. Planet-scale energy, maybe solar-scale energy. Energy is conserved. You can't just think really hard and have it. At minimum you have to already have the energy and materials to build a machine that will let you (mostly build another machine that lets you) harness that much energy.

It's at least not something you'll do by accident.

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

#47

Post by echelon »

andrewflnr wrote: post #46
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…

Leaving aside the fact that there's no evidence superintelligence is even possible, no amount of intelligence alone will let you "trivially" create black holes. Creating black holes requires a ludicrous amount of energy. Planet-scale energy, maybe solar-scale energy. Energy is conserved. You can't just think really hard and have it. At minimum you have to already have the energy and materials to build a machine that…

You don't know any of that.

We are primitive apes. We are all uniformly dumb.

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

#48

Post by antognini »

sgt101 wrote: post #8

Could this kind of trigger effect the standard candle application of Type 1a's? For example, if a black hole triggers a type 1a and that perturbs the type 1a light curve in some way (possibly because less mass could be consumed in the explosion than you would get if one was triggered by mass accretion) and the rate of triggering of this kind changed over time as the universe aged and somehow the population of primord…

They did some modeling in a previous paper of how this would impact Ia supernovae and it depends on whether the supernova is driven by Kelvin-Helmholtz instabilities or not. In the case that it is, this would only trigger Ia supernovae for white dwarfs which are already very close to the Chandrasekhar mass. In this case the standard candles would be pretty much the same.

In the case that KH instabilities are weaker they claim that you can get supernovae at masses farther from the Chandrasekhar limit. This could plausibly have more of an impact on Ias as standard candles. (Though perhaps less than you might think becauseit would also likely have an effect on the shape of the light curve, and Ias are normalized based on their light curve shape.)

All that said, even if this process does occur, I doubt the rates would be high enough for it to be a substantial fraction of observed Ias.

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

#50

Post by antognini »

cousinbryce wrote: post #5

Anyone have guesses about how a transiting primordial black hole would effect a Sun like star? Paper is about tidal forces inducing supernova in white dwarfs. For that matter how might it effect sea tides?

We have constraints that primordial black holes must be less than the size of a large asteroid. They would be gravitationally insignificant to the Earth unless they actually passed through it.

I also don't think it would really be detectable in the Sun. Perhaps there would be some transient astroseismology signature.

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