# Could yet unobserved baryons constitute useful building materials?

The setting is a science fiction story set roughly 500 years in the future.

Looking at Wikipedia, I see a number of baryons that have so far never been observed. I'm interested in exploring this subject, and wonder if those baryons could have useful properties for futuristic technologies.

First, could those particles stable enough to allow to build things with them, and would it be possible to manufacture them in the future ? If so, could they potentially be used to build materials with very high resistance, very low or very high mass, etc. ?

For example, a high resistance, low mass material made of manufactured baryons could be useful to build military vehicles or as protection. A high resistance but transparent material could be used as windows on warships. Or any other properties related to bendability, electric conductivity, etc.

What I'm really asking for is, how much flexibility (based on our current knowledge) do those unobserved baryons offer me to imagine futuristic technologies?

• Handwaving some heavier and unexpectedly stable chemical element made of usual protons and neutrons is way safer. A new island of stability is still possible (or at least unchecked). – fraxinus Apr 9 at 8:48

Of all the baryons listed in the page you quote, the only two having a lifetime not ending with a negative exponential are proton and neutron. All the others live for something like $$10^{-10}$$ seconds at most.

If statistics matters, and we support it with the empirical evidence that none of those has been yet observed in our "low energy" world (meaning the world we see outside of particle accelerators), I would bet that none of the yet to be observed baryons will live any longer than its cousins.

Thus, none of them in itself will be suitable for doing anything besides helping its finder publishing a paper in particle physics and getting maybe quoted in some popular magazine.

• What if they were to be found to be metastable in artificially-occurring combinations with other baryons, like how neutrons become stable when in an atomic nucleus? – nick012000 Apr 9 at 2:36
• @nick012000, let's say it is possible: where are they? – L.Dutch - Reinstate Monica Apr 9 at 6:22
• @nick012000 Even if you find some metastable species, it will be still hard (speaking of energy and technology) to create them in visible amounts. (2) The neutrons have the luxury to be only a tiny bit heavier than the proton, so you can hide the difference in the binding energy of the nucleus. That's why they appear stable. Any other baryon is WAY heavier and you need some crazy binding energies in order to keep it stable. The strong interaction is of no help here, gravity - maybe, in a neutron star scales. – fraxinus Apr 9 at 8:41

It is exceedingly unlikely. Expanding on L.Dutch's answer: The fact that these baryons are undiscovered at all disproves the idea that they could be stable. If they were stable, there would be tons of them everywhere and we would have easily detected them. You might say they could be only slightly unstable; maybe they have half-lives of millions of years. None created in the Big Bang would still exist, but any new ones we create in particle accelerators would last for thousands of years. Except this doesn't work either. Every day countless cosmic rays impact the upper atmosphere of the Earth with more energy than any particle accelerator. If these baryons could be created at energy levels we could reach in a lab, we should see them forming naturally in the upper atmosphere. Now you may say that even these collisions aren't strong enough. But this too, does not really work. We see many cosmic phenomena with vastly more energy than the cosmic ray interactions I mentioned above. Supermassive black holes accreting matter, quasars blasting out jets of particles, and hypernovae to name a few. And yet we still don't see these baryons being created. So it seems like they either are all unstable or they cannot be created by simply smashing particles together.

This opens one last possibility which may work. Maybe there is some other technique no one has thought of, other than smashing things in a particle accelerator, that actually will work. But this seems like the kind of thing that's so hypothetical it may as well be magic.

• "disproves the idea that they could be stable" -> "is good evidence that they could never be stable" – Mad Physicist Apr 9 at 2:55
• To be fair, just about all the things you said today were magic a couple of hundred years ago. – Mad Physicist Apr 9 at 2:56
• Just to make sure, I completely agree with your answer (+1 and all). – Mad Physicist Apr 9 at 2:57

# Construction is plain out

If these particles actually exist, they haven't been observed, this means that they are either:

A. Are unstable and would exist for only a tiny fraction of a second (as has been mentioned in other answers).

B. For some other reason they are difficult to detect, or in other words, they do not have strong interactions with other particles or waves that we can observe.

So if there were a stable type of unobserved particle that was a useful material for building things, then it would be able to be observed by the way you're wanting it to interact with the physical world. So this kind of usefulness is out of the question.

# However ...

Technology sometimes relies on things other than constructing things. If a technology were made that could detect the previously undetected particles, then only people with access to this technology could observe them. This makes them excellent candidates for communicating things, perhaps secret things.

For example, radio waves are invisible to us, but if we have the technology, we can use them to transmit signals between remote locations. The fact that you now have a near invisible particle might evolve technologies that rely on the difficulty others would have in detecting it.

• Lots of sci-fi (and of course actual history) is based on the restriction of disruptive technologies. – Mad Physicist Apr 9 at 2:58
• Let's also not forget the possibility that these particles could potentially interact with each other, so creating vast quantities of them (using the time-tested technology of handwavium) could create materials that have some very interesting interactions with our normal world (so more handwavium). – Mad Physicist Apr 9 at 3:00

Matter existing at "low temperatures" is stable only in the first generational stage of matter. Here "low" is very relative and in this sense millions of Kelvin is still considered low temperature.

The first generation of matter is comprised of three particles: Up and Down quarks and electrons which it is no coincidence that these are the only types of matter we observe on a day-to-day basis. Note that matter quarks form bound states in three's and there are only two possible combinations with two quarks; which are known as the proton and the neutron.

Unlike chemicals, formed from numerous atoms which can occupy nearly endless collection bound states, restricted by a huge number of factors. Matter Quarks (which comprise baryons) have only one bound state called a triplet involving exactly three quarks. For all interactions, if it is energetically favorable to decay, the bond will break apart and the constituents will arrange in the lowest energy configuration possible. Quarks are no different; very energetic high mass bound states such as Xi or Sigma baryons will rapidly decay, so quick is this dissolution in fact, that only the tell-tale sign of their existence is the way their low energy constituents are observed to move into detectors within particle accelerators.

So unless there is some very bizarre unobserved physics which would allow for low-energy quarks to occupy bound states other than triplets, or a mechanism which forbids high energy bound quarks from decaying and thus occupying meta stable states, then it is simply impossible for any other stable baryons to exist.

Since we have been searching for exotic states of matter for the better part of half a century, and since the number of available interactions are so few, it is quite reasonable to assume that we would have observed any other stable baryons by now.

Possible fictional scenarios which might allow a way for physical analogs to come into play might be an event which a black hole is ripped apart. Realistically this event has never been observed and currently is theoretically impossible. However, if such an event could occur it is conceivable that massive stable baryons could emerge in a similar analogy to how stable heavy elements emerge from supernova and neutron star collisions.