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New form of matter may lie just beyond the periodic table

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Re: New form of matter may lie just beyond the periodic table

#31

Post by time-of-flight »

WiseWeasel wrote: post #6
igravious wrote: post #4

Earlier quoted context omitted.

So what is the QM that is found in colliders? “When produced in a collider, quark matter typically decays within a fraction of a second into stable hadronic matter (with bound quarks).” Obviously not udQM, right?

> SQM consists of comparable amounts of up, down, and strange quarks. One of the new results of the latest study is that quark matter without strange quarks, i.e., udQM, has lower bulk energy per baryon than either SQM or hadronic matter, making it energetically favorable. I would guess QM composed of strange quarks in addition to up and down , and/or below the "continent of stability" size of 300 Angstroms[1]. [1] C…

Just a clarification: A here doesn't mean Angstroms. It means "number of nucleons", as in carbon-12 is an A=12 system.

So they're saying A>300 means "a quark system with >900 quarks"; normal protons and neutrons have three quarks a piece.

If I misinterpreted your comment and the above was already clear to you, please forgive my mistake (I didn't want anyone to confuse A for angstroms here).

Re: New form of matter may lie just beyond the periodic table

#32

Post by WiseWeasel »

time-of-flight wrote: post #31
WiseWeasel wrote: post #6

Earlier quoted context omitted.

> SQM consists of comparable amounts of up, down, and strange quarks. One of the new results of the latest study is that quark matter without strange quarks, i.e., udQM, has lower bulk energy per baryon than either SQM or hadronic matter, making it energetically favorable. I would guess QM composed of strange quarks in addition to up and down , and/or below the "continent of stability" size of 300 Angstroms[1]. [1] C…

Just a clarification: A here doesn't mean Angstroms. It means "number of nucleons", as in carbon-12 is an A=12 system. So they're saying A>300 means "a quark system with >900 quarks"; normal protons and neutrons have three quarks a piece. If I misinterpreted your comment and the above was already clear to you, please forgive my mistake (I didn't want anyone to confuse A for angstroms here).

Ah, thank you for the clarification.

Re: New form of matter may lie just beyond the periodic table

#33

Post by gus_massa »

ChuckMcM wrote: post #27
sp332 wrote: post #19

Earlier quoted context omitted.

When particles come together and form a nucleus, it releases energy. This energy is because the new form is more energetically favorable, that is it requires less energy than the particles had separately. This is what makes it stable - it requires input of energy to undo the release of energy. (It doesn't guarantee that some other state is even more stable, like some kind of fission. But going directly back to the fo…

I'm up to speed on the physics behind fusion and fission, what I am missing is this fractional fusion/fission idea with respect to quarks. The suggestion was (as I understand it) that one could "inject/collide/drop" a neutron onto this matter and the neutron would then fission into it's component quarks, capturing them and releasing the binding energy. So this stable matter is a quark soup held together by the strong…

I think they don't have any experiment results, only some new (unproven) theoretical ideas.

Moreover, I'm skeptical because a similar idea may apply in neutron starts, but the current model of neutron starts has a crust of about 100m (300ft) that has different kinds of intermediate structures with a lot of neutrons and protons and is called "nuclear pasta" https://en.wikipedia.org/wiki/Nuclear_pasta

I can't find how much experimental support has nuclear pasta, but IIUC there are some measurements of the density of the layers of the neutron stars https://en.wikipedia.org/wiki/Neutron_star#Density_and_press...

Re: New form of matter may lie just beyond the periodic table

#34

Post by ianai »

time-of-flight wrote: post #23
ChuckMcM wrote: post #12

"If quark matter is found (or produced in accelerators), it may be stored and then fed with slow neutrons or heavy ions. The absorption of these particles means a lower total mass and thus a release of energy, mostly in the form of gamma radiation. Unlike nuclear fusion, this is a process that should be easy to initiate and control." -- Bob Holdom Oh really? Does the paper give any idea about how that might be accomp…

Neutrons are a pain to control as a beam because they have no charge, so methods employing electric or magnetic optics are not applicable. Typical pocket sources use the alpha(9Be,12C)n reaction to produce neutrons; if you have a reactor handy, you can moderate (slow) the neutrons produced and use them... this would be by far the most economical option. As a nuclear chemistry PhD, I am highly skeptical of the practic…

Do you see any modification to it being feasible?

Re: New form of matter may lie just beyond the periodic table

#35

Post by qubex »

semi-extrinsic wrote: post #14
jonsen wrote: post #7

... quark matter has the potential to be used as a new source of energy A new kind of weapon? Renewing the nuclear arms race?

No. For one, the PRL paper linked here is highly speculative, using a phenomenological model and a lot of assumption and extrapolation. It's full of "may" and "if" and "possibility". Furthermore, what they suggest appears like it would only work as an (inefficient) energy storage; it's not a primary energy source, since you'd have to spend lots of energy first to create this very hypothetical quark matter,and then re…

The inefficiency is comparable to those who advocate using antimatter as the ultimate fuel, somehow forgetting that it needs to be manufactured somehow at great energetic expense. If one has a Dyson sphere’s worth of energy to power one’s antimatter-production plant for one’s ultrarelitivistic fleet, that’s great; but if you’re thinking of massive conventional fusion reactors as an intermediary might as well just take those (and their large amounts of light fuels) along for the ride and cut out the intermediary product.

Re: New form of matter may lie just beyond the periodic table

#36

Post by [deleted] »

sametmax wrote: post #13
jonsen wrote: post #7

... quark matter has the potential to be used as a new source of energy A new kind of weapon? Renewing the nuclear arms race?

What would be the point ? We can already destroy a medium country with a few nukes. We probably have enough nukes to blow the entire planet. What would a bigger boom accomplish ?

[deleted]

Re: New form of matter may lie just beyond the periodic table

#38

Post by garmaine »

time-of-flight wrote: post #23
ChuckMcM wrote: post #12

"If quark matter is found (or produced in accelerators), it may be stored and then fed with slow neutrons or heavy ions. The absorption of these particles means a lower total mass and thus a release of energy, mostly in the form of gamma radiation. Unlike nuclear fusion, this is a process that should be easy to initiate and control." -- Bob Holdom Oh really? Does the paper give any idea about how that might be accomp…

Neutrons are a pain to control as a beam because they have no charge, so methods employing electric or magnetic optics are not applicable. Typical pocket sources use the alpha(9Be,12C)n reaction to produce neutrons; if you have a reactor handy, you can moderate (slow) the neutrons produced and use them... this would be by far the most economical option. As a nuclear chemistry PhD, I am highly skeptical of the practic…

You'd just just a neutron reflector to shape an omnidirectional source, right?

Re: New form of matter may lie just beyond the periodic table

#39

Post by drak0n1c »

inetknght wrote: post #37

This page, or something it loads, is causing Firefox to use 100% CPU. Cryptocurrency malware, perhaps?

physorg has been a very popular site ever since 2004 and well respected for its compilation of scientific and technical papers. It's probably not malware - a more reasonable and common explanation for bad CPU performance is that one of the web or ad frameworks they use is poorly made.

Re: New form of matter may lie just beyond the periodic table

#40

Post by rwallace »

Neutron stars would presumably consist in large part of QM, if it exists.

Colliding neutron stars spray large chunks of material therefrom, into interstellar space. It is said that this contributes a significant percentage of the gold and uranium on Earth.

If QM were stable, would we not therefore expect to observe it in nature, with abundance at least on the order of gold and uranium? Perhaps there is some factor that depresses its abundance somewhat, but to have gone entirely unobserved, it would have to be many orders of magnitude less abundant than gold. Is there any theory that reconciles stable QM with the observed upper bound on abundance?

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