Black hole in a quark query.

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A Traditional Eccentric!
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Help! This comes under the 'this is such a stupid question, but I don't the answer' heading.

Why can't we have a black hole in the centre of a quark? Or putting it another why can't a quark become black hole?
 
I don't really understand your question.

Just off the top of my head, riffing on what you've said, we don't have any theories that posit a quark (or squark - the supersymmetric equivalent of a quark) with a mass big enough to generate a black hole. It's all down to the mass of the particle.

But, let's suppose someone comes up with some beefy version of supersymmetry...then such a 'squark' wouldn't really be a squark, surely - it would be a micro-blackhole. That would probably decay really quickly (even if it was just one quark, there would be a decay path that would quickly get rid of it, I presume.) The Hawking 'radiation' should be intense for such a small blackhole.*

In terms of really dense particles, the proposed mass of a magnetic monopole is so high - but not so high that it becomes a black hole - that people have suggested we could use one (if we could find one) to actually create a new universe. But then some theories have it that there can be only one magnetic monopole in the entire universe - so good luck actually finding it! Oh and the sort of particle accelerator you'd need to initiate the process with the monopole is probably physically impossible.

==================================

* theoretical blackholes of one particle get a bit strange.
 
Though not exactly what the question asked, quarks and black holes may have similar densities (mass is still an important component). The attached specifies the density of atomic nuclei and black holes. Correct me if I'm wrong, but I though quarks were the building blocks of protons and neutrons.

The issue, I believe that even though the densities are similar, the total mass of a quark is not enough to cause the gravity that a black hole exhibits.

 
I’ve often wondered this (forgive my ignorance if it is an utterly silly idea)….

As far as I understand it, mass is actually an interaction with the Higgs field and this defines the mass of a ‘particle’ (which I understand to be a collapsed waveform or excitation of a field).

What if we could change how a particle interacted with the Higgs field? Could we actually change the mass of a particle?
 
I’ve often wondered this (forgive my ignorance if it is an utterly silly idea)….

As far as I understand it, mass is actually an interaction with the Higgs field and this defines the mass of a ‘particle’ (which I understand to be a collapsed waveform or excitation of a field).

What if we could change how a particle interacted with the Higgs field? Could we actually change the mass of a particle?
Surely, if as you stated, mass is the interaction with the Higgs field, and we changed how a particle interacted with the Higgs field, then it would change the mass by definition.

Though not exactly what the question asked, quarks and black holes may have similar densities (mass is still an important component). The attached specifies the density of atomic nuclei and black holes. Correct me if I'm wrong, but I though quarks were the building blocks of protons and neutrons.

The issue, I believe that even though the densities are similar, the total mass of a quark is not enough to cause the gravity that a black hole exhibits.


This is interesting but density kinda hides a lot of issues. The volume of a black hole is calculated using the Schwarzchild radius, or event horizon. But an event horizon is 'porous' not a hard limit. If you were flying a spaceship past the event horizon of Sagittarius A* you would not notice it - it's still normal space-time. The mass inside is much smaller

By definition a black hole is an object whose real radius is smaller than its Schwarzchilds radius which also indicates that the mass inside this radius is causing the curvature of spacetime to become infinite at some point inside.

So for example:

The Schwarzchild radius of the Sun is ~3km but it's actual radius is ~700,000km
and of a human is ~1 x10-25km but actual radius about 50cm! (Using a physicists definition of the radius of a human :))

When it comes to particles it gets a bit more complicated because, yes, we treat elementary particles like electrons and quarks as point particles - i.e. they are infinitesimal in size. So...if the volume is infinitely small, then no matter what the mass is, surely they will be infinitely dense - or we have a definite positive Schwarzchild radius (see below) but it's actual volume/radius is essentially zero, and should therefore curve spacetime infinitely.

But point particles is a theoretical concept which helps the maths. If we take quantum mechanics into account, the 'size' of a particle, which can be represented by a wavefunction, is 'spread out'.

So to give you some numbers.

mass of a Proton is 1.67 x10 ^ -27 kg. It's Schwarzchild radius is ~2.5 x 10 ^ -54 m. It's "quantum radius" can be calculated to be: ~1 x 10 -15 m

For the biggest quark that we've measured, the Top quark

It's mass is approximately 3 x 10 ^ -25 kg, giving a Schwarzchild radius of ~4.5 x 10 ^ -52 m, whereas it's quantum radius would be ~7 x 10 -18 m

As you can see the 'real' radius of the particle is much bigger than the Schwarzchild radius. For a 'point particle' to become a black hole, I believe, it's mass has to be of order 0.1 milligrams, using the above calculations!

I think the other way of looking at the above is that it's telling you that the mass of any of the quarks we know about does not make the curvature of space-time around them infinite.
 
Thank you one and all for your considered responses. Basically Venusian Broon is indicating the size of the quark is bigger than its Schwartzchild radius, which is why it is not a black hole.

To me, it seems momentum from the Big Bang, electromagnetism, and strong and weak nuclear forces are all working against mass becoming a black-holed. For instance the positively charged protons in a nucleus push each other away while their masses will be attracted gravitationally. In turn a proton comprises two up quakes (electonagnetic charge +2/3) and one down quark (electromagnetic charge -1/3). So I can see why a proton would resist becoming a black hole (positive charges replying each other).

However, the mass of the up quark is 1.7-3.3 MeV. So it should be suffering from gravity pulling the mass in on itself. What is keeping it as an entity stable?
 
The strong nuclear force perhaps. I think I remember reading somewhere that gravity is the weakest force at this scale.
 

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