
The Subatomic Discovery That Physicists Considered Keeping Secret - wjSgoWPm5bWAhXB
https://www.livescience.com/60847-charm-quark-fusion-subatomic-hydrogen-bomb.html
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gus_massa
The article hardy makes any sense. You can't make a fusion of bottom quarks
because they don't stick together. Reading the abstract of the paper,
[http://www.nature.com/nature/journal/v551/n7678/full/nature2...](http://www.nature.com/nature/journal/v551/n7678/full/nature24289.html)
the reaction is

Lambda_b + Lambda_b -> Xi_bb + n

(up+down+bottom) + (up+down+bottom) -> (up+bottom+bottom) + (up+down+down)

This makes sense because each quark is inside a baryon with three quarks.

They say this is equivalent to the fusion of

D + T -> He + n

[proton+neutron] + [proton+neutron+neutron] -> [proton+proton+neutron+neutron]
+ neutron

[(up+up+down)+(up+down+down)] + [(up+up+down)+(up+down+down)+(up+down+down)]
-> [(up+up+down)+(up+up+down)+(up+down+down)+(up+down+down)] + (up+down+down)

The analogy is very very very week. They are very different reactions.

The worse part is the total linkbait title. If you somehow magically can
create a lot of Lambdas_b, in a very small time all of them will get
transformed into protons, electrons and a lot of gamma rays. If you have
enough you will have a nice explosion.

But if in the middle of the transformation they collide and produce some
Xi_bb, the Xi_bb's will decay soon into protons, electrons and a lot of gamma
rays. You don't get more energy because some of the Lambda_b get temporaly
transformed into Xi_bb, the final energy is the same, so the risk is obviously
zero.

For comparison, Deuterium is stable and Tritium is almost stable, so you can
produce and accumulate them conveniently. And a bunch of Deuterium and Tritium
will not cause spontaneously a nuclear explosion. But if you convince them to
undergo fusion, you get a nice explosion. The final products are stable Helium
and almost stable neutrons, so this reaction is enabled because Helium exist,
so D+T->He+n is interesting.

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Knufen
I think we are nearing click bait here, which is becoming a more and more
common on HN

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nerdponx
How so? It's the original title, and it aptly described the article.

We are probably just becoming more sensitive and resistant to having our
feelings manipulated constantly. Which I think is a good thing.

Edit:On second thought, I got further in the article and it's clear that the
whole "we almost kept it secret" angle is a total stretch created by the
author to make for a more exciting read. Yeah, this is click bait. Although,
it's cool to know that you can theoretically smash two quarks together and get
a boom.

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philtar
Just because it's the same as the original title doesn't mean it's not click
bait. It just means the original title is click bait too.

A non clickbait-y title would explain what the article was about instead of
creating mystery so you would follow through.

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ruminasean
1 picosecond is about the time it takes light to travel half the length of a
single grain of salt. What a Joycean level of measurement.

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cuspycode
The article talks about fusion chain reactions in hydrogen bombs, but the
fusion in hydrogen bombs isn't an exponential sequence of chain reactions,
it's due to very high temperatures caused by _fission_ chain reactions in the
primary. Hence the term "thermonuclear".

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hliyan
Despite the fact that a bottom quark fusion event emits 18 times the energy of
traditional fusion (deuterium nuclei), the discoverers note that it's not
possible to create a chain reaction of bottom quark fusions. So there are no
military applications (or energy applications for that matter).

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otp124
> a bottom quark fusion event emits 18 times the energy of traditional fusion

Small correction. The article says the MeV is 8x not 18x

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hliyan
Ah, I stand corrected.

