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Tiny black holes may be exploding stars across the Milky Way

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

#61

Post by criddell »

rigrassm wrote: post #57
istjohn wrote: post #45

Earlier quoted context omitted.

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

I love Sean Carroll (Something Deeply Hidden and From Eternity to Here are the root of my fascination with physics and endless pondering of the nature of time) but I have to disagree with his take on this. Hypothesis - a proposed explanation for something (such as a phenomenon of unknown cause) that is tentatively assumed in order to test whether it agrees with facts that are known or can be determined. Theory - a sc…

Isn't Planck's hypothesis really a theory? Isn't string theory really a hypothesis?

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

#62

Post by cindyllm »

bell-cot wrote: post #60
ben_w wrote: post #53

Earlier quoted context omitted.

> Yeah. 5 ly sounds much safer. Well yeah. I clearly could've phrased this better though: I was aiming for "here is an example distance which *is* bad", not as it appears to have been understood "here is the distance where it is *not* bad".

I mostly noticed your "might have an unplesant climate impact by increasing the eccentricity of our orbit", and thought that'd be the least of Earth's worries. Black hole gravity is ruthless about turning nearby mass into deadly fireworks.

[dead]

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

#63

Post by ck2 »

If I remember correctly, Stephen Hawking had to do some serious math in the 1970s to convince himself a tiny black hole was not hiding in our Sun

I think there's a PBS Space Time on it (of course)

adding: yup! love that show

* https://www.youtube.com/watch?v=Q6kJaMf3Lgo

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

#64

Post by shagie »

jandrewrogers wrote: post #54
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?

Most likely minimal? The mass is low. I am, however, reminded that the orbit of the asteroid Juno (~250km diameter) permanently changed in 1839 without an obvious cause.

How to spot tiny black holes that might pass through the solar system - https://www.sciencenews.org/article/primordial-black-holes-s...

And the referenced papers:

Probing primordial black holes and dark matter clumps in the Solar System with gravimeter and Global Navigation Satellite Systems networks - https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.0...

Close encounters of the primordial kind: A new observable for primordial black holes as dark matter - https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.0...

And the PBS Spacetime: How Many Black Holes Are In The Solar System? - https://youtu.be/wh75ubECL8I

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

#65

Post by andrewflnr »

echelon wrote: post #56
andrewflnr wrote: post #51

Earlier quoted context omitted.

It's inherent to the math that defines the entire concept of a black hole, or "spacetime" in general. So to the extent we can contemplate the question at all, we can be pretty confident that creating black holes is Very Hard. There's a lot we don't know, but the fact that the universe is consistent means it has to be consistent with what we do know already. Don't be so openminded your brain falls out.

> the fact that the universe is consistent We don't know this either. We are very limited in detection. Our energies are small. How "standard" are standard candles and other references? Are the facts that stand as the basis for our theories even correct? We are too primitive to be dealing in absolutes.

> > the fact that the universe is consistent

> We don't know this either.

See this is what I'm talking about as far as being too open-minded. Consider what it would mean for the universe to be inconsistent, particularly in relation to the astronomical observations that are the basis of this conversation.

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

#66

Post by SoftTalker »

jandrewrogers wrote: post #54
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?

Most likely minimal? The mass is low. I am, however, reminded that the orbit of the asteroid Juno (~250km diameter) permanently changed in 1839 without an obvious cause.

Wouldn't low-mass primordial black holes have evaporated by now?

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

#67

Post by shagie »

ungovernableCat wrote: post #43
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.

Not quite so undetectable... in theory.

PBS Spacetime - How Many Black Holes Are In The Solar System? https://youtu.be/wh75ubECL8I

And then How to spot tiny black holes that might pass through the solar system - https://www.sciencenews.org/article/primordial-black-holes-s...

That references two papers:

Probing primordial black holes and dark matter clumps in the Solar System with gravimeter and Global Navigation Satellite Systems networks - https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.0...

Close encounters of the primordial kind: A new observable for primordial black holes as dark matter - https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.0...

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

#68

Post by ButlerianJihad »

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…

Origami Black Hole https://m.xkcd.com/3033/

"It Really Brings the Room Together" https://m.xkcd.com/1680/

M87 Size Comparison https://m.xkcd.com/2135/

Black Hole Moon https://what-if.xkcd.com/129/

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

#69

Post by shagie »

ttul wrote: post #36
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.

Can one detect passage of small black hole through the Earth? - https://arxiv.org/abs/0710.3438v1

A physics stack exchange answer about it: https://physics.stackexchange.com/a/55184

The most relevant part:

> The total energy created by a PBH roughly equals the energy produced by the detonation of one tonne of TNT, but this energy is the total energy it deposits along its path through the Earths diameter, not the energy it produces on impact. So don’t expect a magnificent explosion, we’d be lucky to see a spark as it hits the ground.

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

#70

Post by Tuna-Fish »

jandrewrogers wrote: post #54
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?

Most likely minimal? The mass is low. I am, however, reminded that the orbit of the asteroid Juno (~250km diameter) permanently changed in 1839 without an obvious cause.

Note that the orbital perturbation of Juno in 1839 was of rather low magnitude, and could have been caused by an asteroid as small as ~1km diameter. Based on current models, there are potentially more than a million rocks that big in the belt still undiscovered.
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