<ol>
<li><p>A buckyball is about a nanometre (<span class="math-container">$10^{-9}$</span> m) across. If you limit the charge on the black hole to something like that of an electron or a few electrons, then this would mean the event horizon(s) of a charged, spinless, <a href="https://en.wikipedia.org/wiki/Reissner%E2%80%93Nordstr%C3%B6m_metric" rel="noreferrer">Reissner-Nordstrom</a> black hole would be almost indistinguishable from that of a Schwarzschild black hole. The mass of this black hole would therefore be around <span class="math-container">$r_s c^2/2G \simeq 10^{18}$</span> kg. Yes, this is theoretically possible and maybe such black holes <a href="https://en.wikipedia.org/wiki/Primordial_black_hole" rel="noreferrer">were produced</a> during the big bang and are still around today.</p>
</li>
<li><p>For Coulomb forces to outweigh gravitational forces then you need
<span class="math-container">$$ \frac{Q^2}{4\pi \epsilon_0} &gt; G M_{\rm BH}{m_C}\ .$$</span>
In this case <span class="math-container">$Q \sim 10^{-18}$</span> Coulombs, <span class="math-container">$M_{\rm BH}\sim 10^{18}$</span> kg, <span class="math-container">$m_C = 12\times 1.67\times 10^{-27}$</span> kg. The LHS is <span class="math-container">$\sim 10^{-26}$</span> Nm<span class="math-container">$^2$</span> and the RHS is <span class="math-container">$\sim 10^{-18}$</span> Nm<span class="math-container">$^2$</span>. So perhaps surprisingly, gravity will win and the buckyball will almost instantly be incorporated into the black hole.</p>
</li>
<li><p>We don't have a theory governing the quantum behaviour of black holes. A singularity doesn't really have a size in a non-spinning black hole.</p>
</li>
<li><p>A <span class="math-container">$10^{18}$</span> kg black hole would evaporate via Hawking radiation in about <span class="math-container">$10^{30}$</span> years.</p>
</li>
</ol>

CC BY-SA 4.0
2022-03-24T20:41:59.280Z
Thanks, @ProfRob, I was hoping you would answer.   You're so very informative.  So if I can get the RHS down, it's theoretically possible - but I'll have to do the math.  I couldn't find anything to determine the inside radius of a Buckyball, not impacting the cabin electron shells.  Wouldn't that matter?
RoUS
CC BY-SA 4.0
2022-03-25T10:07:29.370Z
"Yes, this is theoretically possible and maybe such black holes were produced during the big bang and are still around today." @user253751
ProfRob
CC BY-SA 4.0
2022-03-25T14:55:39.150Z
Is there a reason you limited the charge to a few electrons? How would things change if you increased the charge to be sufficient for electromagnetism to win out over gravity?
Michael
CC BY-SA 4.0
2022-03-24T20:19:17.980Z
2022-03-24T21:55:17.157Z
2022-03-24T21:55:17.157Z
ProfRob
<p>The first item is the basic question; the subsequent items build upon it if it's possible.  If these need to be broken into separate questions, I can do that, but they're pretty tightly related.</p>
<ol>
<li>Is a non-rotating negatively-charged singularity small enough to be contained by a C₆₀ Buckyball theoretically possible?</li>
<li>Would the charge repulsion of the carbon electrons be stronger than the gravitational attraction, keeping the singularity from consuming them?</li>
<li>Is it theoretically possible for a singularity to be too small to absorb hadrons or even elementary particles?</li>
<li>Anything this small would doubtless evaporate very quickly, but just how long <em>could</em> they last?</li>
</ol>
<p>Thanks!</p>

CC BY-SA 4.0
2022-03-25T22:39:25.283Z
I think it all looks like an X & Y problem. Idea of getting canned BH isn't particularly good. Yeah, there's idea of something like that with antimatter, but it's already far-fetched. Another issue is that you shouldn't mix up concepts of singularity and black hole. BTW I think questions like that are more suitable for Physics.SE, or maybe Worldbuilding.SE - while the answer mentions, still quite big, primordial black holes, it's not like even smaller ones aren't *hypothetically* possible, but have more to do with physical speculation the astronomy.
Mithoron
<black-hole><singularity><molecules>
Are Buckyball-sized black holes possible?
RoUS
# Are Buckyball-sized black holes possible?

(Asked by: username_0 on 2022-03-24)

The first item is the basic question; the subsequent items build upon it if it's possible. If these need to be broken into separate questions, I can do that, but they're pretty tightly related.

1. Is a non-rotating negatively-charged singularity small enough to be contained by a C₆₀ Buckyball theoretically possible?
2. Would the charge repulsion of the carbon electrons be stronger than the gravitational attraction, keeping the singularity from consuming them?
3. Is it theoretically possible for a singularity to be too small to absorb hadrons or even elementary particles?
4. Anything this small would doubtless evaporate very quickly, but just how long *could* they last?

Thanks!

**Tags:** black-hole, singularity, molecules

> **Comments:**
> **username_1**: I think it all looks like an X & Y problem. Idea of getting canned BH isn't particularly good. Yeah, there's idea of something like that with antimatter, but it's already far-fetched. Another issue is that you shouldn't mix up concepts of singularity and black hole. BTW I think questions like that are more suitable for Physics.SE, or maybe Worldbuilding.SE - while the answer mentions, still quite big, primordial black holes, it's not like even smaller ones aren't *hypothetically* possible, but have more to do with physical speculation the astronomy.  

---

## 1 answers

### Answer by username_2 on 2022-03-24. Score: 18 | Accepted answer

1. A buckyball is about a nanometre ($10^{-9}$ m) across. If you limit the charge on the black hole to something like that of an electron or a few electrons, then this would mean the event horizon(s) of a charged, spinless, [Reissner-Nordstrom](https://en.wikipedia.org/wiki/Reissner%E2%80%93Nordstr%C3%B6m_metric) black hole would be almost indistinguishable from that of a Schwarzschild black hole. The mass of this black hole would therefore be around $r\_s c^2/2G \simeq 10^{18}$ kg. Yes, this is theoretically possible and maybe such black holes [were produced](https://en.wikipedia.org/wiki/Primordial_black_hole) during the big bang and are still around today.
2. For Coulomb forces to outweigh gravitational forces then you need
   $$ \frac{Q^2}{4\pi \epsilon\_0} > G M\_{\rm BH}{m\_C}\ .$$
   In this case $Q \sim 10^{-18}$ Coulombs, $M\_{\rm BH}\sim 10^{18}$ kg, $m\_C = 12\times 1.67\times 10^{-27}$ kg. The LHS is $\sim 10^{-26}$ Nm$^2$ and the RHS is $\sim 10^{-18}$ Nm$^2$. So perhaps surprisingly, gravity will win and the buckyball will almost instantly be incorporated into the black hole.
3. We don't have a theory governing the quantum behaviour of black holes. A singularity doesn't really have a size in a non-spinning black hole.
4. A $10^{18}$ kg black hole would evaporate via Hawking radiation in about $10^{30}$ years.

> **Comments:**
> **username_0**: Thanks, @username_2, I was hoping you would answer.   You're so very informative.  So if I can get the RHS down, it's theoretically possible - but I'll have to do the math.  I couldn't find anything to determine the inside radius of a Buckyball, not impacting the cabin electron shells.  Wouldn't that matter?  
> **username_2**: "Yes, this is theoretically possible and maybe such black holes were produced during the big bang and are still around today." @user253751  
> **username_3**: Is there a reason you limited the charge to a few electrons? How would things change if you increased the charge to be sufficient for electromagnetism to win out over gravity?  

---

