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New exotic matter particle, a tetraquark, discovered at CERN

phys.org

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Re: New exotic matter particle, a tetraquark, discovered at CERN

#31

Post by whatshisface »

8note wrote: post #29
whatshisface wrote: post #22

Earlier quoted context omitted.

Antimatter's reputation for being incredibly difficult to store comes from the fact that it's produced as individual particles. A superconducting antimatter hockey puck would be much easier to store than a cloud of antiprotons of the same mass. And yeah, you'll need a way to build gamma ray mirrors before antimatter reactions will push you in any direction (the energy comes flying out isotropically and we can't prese…

Superconductors pretty notoriously need to be kept cold, which adds another difficulty of cooling the antimatter without touching it

If it was surrounded by a cold mass that it could radiate photons to across a vacuum, its equilibrium temperature would be that of its container.

Re: New exotic matter particle, a tetraquark, discovered at CERN

#32

Post by whatshisface »

amai wrote: post #28

What is the charge of a tetraquark? Is it neutral?

A tetraquark is four quarks. There exist three -1/3e quarks (dsb), three +2/3e quarks (uct), and then their +1/3e and -2/3e antimatter counterparts. 1e is the charge of one electron. The stability of a tetraquark is mainly a color/strong force thing and the electric charge comes along for the ride. Stable atomic nuclei, which are held together by the strong force, go up to +83e and they still don't fall apart due to electric repulsion.

However, there is one constraint that might show up in charge. Tetraquarks always have two antiquarks, which is necessary for the color charge to come out to zero. Working out every possible combination is left as an exercise for the reader. :)

Re: New exotic matter particle, a tetraquark, discovered at CERN

#35

Post by debrice »

MengerSponge wrote: post #30
whatshisface wrote: post #24

Earlier quoted context omitted.

The term "lower energy state" is a funny one, because isn't energy conserved? What's happening is a drop to a more spread out state, where you have several particles making great time flying away from each other instead of one high-energy-density locus in the center. Edit: Just to clarify, the time-variant system exception does not apply in this case. It really is an entropy thing, moreso than an energy thing (which…

Fun fact: in the most general case, energy is not a conserved quantity. https://www.preposterousuniverse.com/blog/2010/02/22/energy-...

Isn’t information a better unit?

Re: New exotic matter particle, a tetraquark, discovered at CERN

#36

Post by teknopaul »

MengerSponge wrote: post #30
whatshisface wrote: post #24

Earlier quoted context omitted.

The term "lower energy state" is a funny one, because isn't energy conserved? What's happening is a drop to a more spread out state, where you have several particles making great time flying away from each other instead of one high-energy-density locus in the center. Edit: Just to clarify, the time-variant system exception does not apply in this case. It really is an entropy thing, moreso than an energy thing (which…

Fun fact: in the most general case, energy is not a conserved quantity. https://www.preposterousuniverse.com/blog/2010/02/22/energy-...

my friend that thinks if he plays the breaks properly on his EV he generates energy, will be happy very hear this.

Re: New exotic matter particle, a tetraquark, discovered at CERN

#37

Post by xhrpost »

mirthless wrote: post #33

Does it fit into the standard model? I thought higgs boson was the last undiscovered particle according to the standard model.

You're referring to elementary particles. This is not elementary as it is composed of Quarks, which are part of the standard model and are elementary.

Re: New exotic matter particle, a tetraquark, discovered at CERN

#38

Post by adrianN »

whatshisface wrote: post #15
Gravityloss wrote: post #13

Earlier quoted context omitted.

So not usable as spaceship fuel

If you're allowed to use something produced in an accelerator as your fuel you can't beat antimatter, which is as stable as normal matter until Kirk orders warp one.

I like black holes because once you have one you don't need an accelerator for refueling. https://arxiv.org/abs/0908.1803

Re: New exotic matter particle, a tetraquark, discovered at CERN

#39

Post by kadoban »

8note wrote: post #29
whatshisface wrote: post #22

Earlier quoted context omitted.

Antimatter's reputation for being incredibly difficult to store comes from the fact that it's produced as individual particles. A superconducting antimatter hockey puck would be much easier to store than a cloud of antiprotons of the same mass. And yeah, you'll need a way to build gamma ray mirrors before antimatter reactions will push you in any direction (the energy comes flying out isotropically and we can't prese…

Superconductors pretty notoriously need to be kept cold, which adds another difficulty of cooling the antimatter without touching it

For now. By the time anyone could even possibly create enough antimatter to matter (heh), critical temperatures should be much higher. The record is broken fairly commonly.

Re: New exotic matter particle, a tetraquark, discovered at CERN

#40

Post by x3n0ph3n3 »

mirthless wrote: post #33

Does it fit into the standard model? I thought higgs boson was the last undiscovered particle according to the standard model.

tetra-quark: 4 quarks. It's composed of particles that are already part of the standard model, just an a previously unseen arrangement.
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