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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

#121

Post by ansible »

whymad wrote: post #81
f6v wrote: 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…

> True for what it is, but this is handled in the books. They literally don’t want our planet, they want our star.

That's... an odd reason. There are plenty of stars out there, unless the aliens started out right next door (like in Alpha Centauri) there's not much reason to go after our star.

I haven't read the books...

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

#122

Post by ansible »

kmm wrote: post #119
danslo wrote: 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!

That is actually quite a long time at the quantum scale.

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

#123

Post by mannerheim »

ansible wrote: post #121
whymad wrote: post #81

Earlier quoted context omitted.

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…

> True for what it is, but this is handled in the books. They literally don’t want our planet, they want our star. That's... an odd reason. There are plenty of stars out there, unless the aliens started out right next door (like in Alpha Centauri) there's not much reason to go after our star. I haven't read the books...

> unless the aliens started out right next door (like in Alpha Centauri)

They did.

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

#125

Post by EthanHeilman »

wisty wrote: post #118
whymad wrote: post #81

Earlier quoted context omitted.

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?

Because the trisolarans didn't know who was out there until they received a message from Earth. They were worried that if they sent a probe to another star then a more advanced civilization perhaps hiding around that star would see the probe arrive, trace the source and annihilate them.

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

#126

Post by roywiggins »

SkyMarshal wrote: post #109
cogman10 wrote: post #95

Earlier quoted context omitted.

Still doesn't make sense. Why limit our tech when they ultimately want to just eliminate us all together? Drop a super virus on us or irradiate the whole planet. Any species capable of disrupting our particle accelerators is more than capable of wiping us from existence.

They could send the subatomic particles from Trisolaris to Earth at light speed, and then use the entangled pair of particles (one on earth, its mate on Trisolaris) to monitor events on earth in real-time. As already said, that preserves the planet, prevents a potential enemy from further developing technologically, and enables real-time monitoring of and interference with that enemy's activities.

>and then use the entangled pair of particles (one on earth, its mate on Trisolaris) to monitor events on earth in real-time.

This, of course, breaks the known laws of physics, since lightspeed is a hard limit on the speed of causality. You can't use entanglement that way in the real world (if QM is anywhere close to correct)

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

#127

Post by yccs27 »

human wrote: post #45
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…

I would be so nervous to be in the middle of space with an hockey puck of antimatter.

I guess I'd be just as nervous in space with thousands of tonnes of explosive propellant. Spaceflight always operates on the very edge of what's possible, not of what's safe.

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

#128

Post by Algol »

WaitWaitWha wrote: post #124

I am unclear if they produced a tetraquark particle, or they simulated the particle. > ... used Google’s quantum computer to demonstrate a genuine ...

I don't see a mention of quantum computers in the article. I think LHCb detected the particle.

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

#129

Post by archsurface »

Why do these things take so long to find? Do they not show up in all collisions - why not, wrong matter, wrong speed? Do they regularly appear, but the "camera" has limitations? Is the "camera" all-seeing, but measurement interpretation inefficient? All/some of the above?

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

#130

Post by EthanHeilman »

cogman10 wrote: post #95
ASalazarMX wrote: post #83

Earlier quoted context omitted.

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.

Still doesn't make sense. Why limit our tech when they ultimately want to just eliminate us all together? Drop a super virus on us or irradiate the whole planet. Any species capable of disrupting our particle accelerators is more than capable of wiping us from existence.

The book makes the claim that the sophons they send over are very limited. It seems reasonable to surmise that they could not create a super virus. Yet they can disrupt sub-atomic experiments. We are talking about an advanced basically magic tech the author made up for the purposes of the plot. So the author can set the rules that the magic tech can do X but not Y.
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