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New exotic matter particle, a tetraquark, discovered at CERN

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

#111
post #54

I recently finished The Three-Body Problem and The Dark Forest, which explore the concept of aliens using their super advanced technology to mess with the results of Earth's particle accelerators, thereby stopping humanity's ability to develop technology based on new physics. Is this discovery exciting? Or are we living in The Three-Body Problem?

It’s a great book, but it suffers from the same old issue. A civilization that is capable of packing a robot into particle by manipulating higher dimensions doesn’t need to take our planet. They could terraform Mars or any other planet they want.

There's also the weird aspect that [rot13'd for spoilers] gur fbcubagf frrz gb or noyr gb vasyhrapr naq dhrel znggre, ohg pna'g frrz gb ernq crbcyr'f zvaqf be xvyy gurz.

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

#112
post #90

Earlier quoted context omitted.

Totally agree with this, the effort to retard development could have been better spent with a myriad of ecosystem destroying actions or geopolitical manipulations. Also just send the indestructible probe to kill every human... My bigger problem with this book was that the author seems to wholely confuse secrecy for strategy. The entire conceit behind the wallfacers seemed ridiculous to me. The best strategic plan nee…

More spoilers below: They actualy did a fair amount of geopolitical manipulations. That formed most of the plot. In the end, it turned out to be MAD that saved us, but setting up the MAD scenario involved secrecy from them (or else they would have stopped us before we could trigger it), and from the rest of humanity (because an official plan to destroy Earth would never have been approved).

It seems like the manipulations were exceedingly silly. It seems like having the sophont start a nuclear war would be straightforward. It was hard for me to suspend disbelief in the sense that it had planet-sized computational power and the ability to manipulate some information on the subatomic level, but couldn't find a vulnerability in aging nuclear launch protocols? The history of near misses with human controlled nuclear weapons suggests a variety of vulnerabilities exist that wouldn't require e.g. directly hacking into command and control. Could it spoof images/data to a sub? Could it cause hallucinations in a large sensor array that feeds data to Norad or a Chinese/Russian equivalent?

Re MAD: I think a plan to destroy Earth would have been easily approved - much like it was in 1960-now, with ICBM and SSBN retaliatory strike capability. Obviously somewhat different in that those MAD-based nuclear wars would be extinctive but not deny the planet to the trisolarians, but the idea that human governments aren't ready to commit to that seems wrong given our history.

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

#113
post #38

Earlier quoted context omitted.

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

Huh, "black holes move when you push them" is interesting. I suppose you could feed it with a beam, but focusing a beam down to attometer-size beamwidth seems like the hardest part, ignoring making a subatomic black hole in the first place. But sure, I suppose capturing the radiation and redirecting most of it back into the black hole to push it and maintain its size, and just enough spare to push the ship itself at the same speed is feasible. Feels like a "free energy" invention but I don't see where it fails, especially if you could capture the majority of the radiation and feed it back into the black hole directionally, minus whatever used to accelerate the rest of the ship.

I see, after more thinking, redirecting the radiation into the black hole would push the ship backwards with equal energy, so half the energy needs to be reflected back into the black hole at the correct direction, and the other half needs to shoot out the back as exhaust, and you'd need additional mass to prevent the black hole from shrinking and getting hotter.

They seem to conceptualize a ~100-year black hole which balances semi-feasible mass, power output, and lifespan, which is radius 2.7 attometers, 1.8 million tons, and 17 petawatts (!) of power. Looks like the saturn V was about 50 GW of power, so having ~500,000x the power, with only less than 1000x the mass (2900 tons vs 1.8m), means this thing would propel at hundreds of G's of acceleration, unless the ship itself was another 500 million tons? It looks like the WTC towers were "only" about 500,000 tons, so if you wanted to drop the acceleration to something survivable by humans, you would either need a much larger, colder black hole, or a ship of proportions of 1,000 WTCs.

The 10-attometer black hole, with "only" 1 petawatt of power and mass 6.7 million tons and lifetime 5,000 years, seems more reasonable, you'd want a ship with mass 58 million tons to have Saturn V levels of acceleration, only 100 WTCs and the black hole is still only about 10% the mass of the ship. Still, this is only about 6x the width of a proton where we're trying to beam on the order of a petawatt. We would probably need a lot of lasers packed densely together near the back of the ship to focus together on this point to avoid the beam itself being near capable of creating black holes, all coming from the same direction where we need to exhaust equally (or more) as much power to get the ship to keep up with the black hole.

Next step would be to figure out how big of a net we'd need to collect enough mass to maintain the black hole but I've spent enough time on this already.

Alcubierre drives almost seem more reasonable than this, almost.

Oh, and the temperature of this thing would be around a trillion degrees, pretty sure most of that radiation would be gamma rays. Need to figure out how to reflect gamma rays with efficiency. This is apparently around the temperature of a SMBH's accretion disk, the temperature of a new neutron star, and the temperature where matter doubles in mass due to relativistic effects.

All this being said, if we can balance the mass of the black hole with that of the ship, with a black hole with lifetime 5000 years, and we achieve 1g constant acceleration, we can cross the galaxy in 24 years and park it for up to a few thousand years before needing to feed it to prevent it from getting too small/hot. https://en.wikipedia.org/wiki/Space_travel_using_constant_ac...

Imagine if you could see the other side of the galaxy and make it back to Earth before you turn 50 (though Earth will have experienced 200,000 years), or, since once you're already at such relativistic speed, see Andromeda and come back before you're 60. Apparently we could round trip to the edge of the (Earth's?) visible universe in right around 100 years. Of course, by time you made it back, Earth would be 26 billion years older, the sun will have exploded, etc. Of course, if these are drone ships, we don't need to worry about human-survivable acceleration, and we could retrieve data much faster, but then no biological lifeform would have been there.

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

#115

Normal human here, can someone speculate on potential industrial uses?

Nobody expects noting. No reason to expect anything whatsoever.

The particle is incredibly short-lived, requires a massive particle accelerator to create, and is hard to detect.

This is just another high-energy physics experiment. The hope is that someday something comes out that does not fit into existing models and is a sign of new physics.

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

#116
post #54

Earlier quoted context omitted.

It’s a great book, but it suffers from the same old issue. A civilization that is capable of packing a robot into particle by manipulating higher dimensions doesn’t need to take our planet. They could terraform Mars or any other planet they want.

There's also the weird aspect that [rot13'd for spoilers] gur fbcubagf frrz gb or noyr gb vasyhrapr naq dhrel znggre, ohg pna'g frrz gb ernq crbcyr'f zvaqf be xvyy gurz.

Gung'f abg dhvgr evtug, gurl qba'g npghnyyl unir gur znff gb rkreg zhpu vasyhrapr ba nalguvat

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

#117
post #54

Earlier quoted context omitted.

It’s a great book, but it suffers from the same old issue. A civilization that is capable of packing a robot into particle by manipulating higher dimensions doesn’t need to take our planet. They could terraform Mars or any other planet they want.

I had the same problem with the books. If the sophon is that omniscient and that powerful, it could do far more than just mess with experiments. I also never understood the wallfacers - why can’t they communicate via encryption, using a private key stored in each individuals mind alone?

How would you use that private key without it 'leaving' your mind?

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

#118
post #81
post #54

Earlier quoted context omitted.

It’s a great book, but it suffers from the same old issue. A civilization that is capable of packing a robot into particle by manipulating higher dimensions doesn’t need to take our planet. They could terraform Mars or any other planet they want.

True for what it is, but this is handled in the books. They literally don’t want our planet, they want our star . And the dark forest: without a history of correlated interaction we have no reason to believe they will allow us to live, so we can’t allow them to live, so they can’t allow us to live. Eliding a more major spoiler, they absolutely intended to annihilate us on arrival and they would have gotten away with…

It's a good book, but while some elements are good sf it's not all hard sf. They're looking for a new planet and didn't even send a probe 50 years ago?

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

#119
post #3

>Such proximity in mass makes the decay "difficult," resulting in a longer lifetime of the particle, and indeed Tcc+, is the longest-lived exotic hadron found to date. So... how long does it live?

Fun fact, the reason strange quarks are named strange is because when we discovered the first hadrons containing those quarks, they were strangely long-lived.

Long-lived here meaning 10^-10 seconds, instead of 10^-20 seconds. A whole tenth of a nanosecond!

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

#120
post #54

Earlier quoted context omitted.

It’s a great book, but it suffers from the same old issue. A civilization that is capable of packing a robot into particle by manipulating higher dimensions doesn’t need to take our planet. They could terraform Mars or any other planet they want.

Super spoiler below: Their tri-solar system was too unstable to terraform, they needed a stable solar system to migrate to. Of course ours was the nearest with an habitable planet (otherwise there wouldn't be much of a story), so they can immediately colonize Earth, and probably begin the centuries-long process of terraforming the neighboring planets.

an aside: i really wish hn had a redaction-style, click-to-reveal spoiler system. not that i don’t appreciate the spoiler warning here — it’s quite kind that people mark their comments as-such — but even when i’ve seen “spoiler warnings” for other content that i’d rather not be spoiled on, it’s very hard to not skim the next few proceeding lines out of habit (especially on mobile). i can’t imagine i’m the only one who does this.
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