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Physicists drive antihydrogen breakthrough at CERN

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Re: Physicists drive antihydrogen breakthrough at CERN

#71

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How could we harness this energy and make it usable?

You use it to boil water.

You can even dissolve the uranium in the water and use the same substance for both fuel and propellant and so capable of reaching far higher temperatures than those that would cause any engine to melt.

https://en.wikipedia.org/wiki/Nuclear_salt-water_rocket

Re: Physicists drive antihydrogen breakthrough at CERN

#72

As a side note, it's mind boggling that overwhelming majority (more than 98%) of the visible universe's mass are only from two most lightweight of chemical elements namely Hydrogen and Helium.

Feels like most resources on the map aren’t mined yet.

Re: Physicists drive antihydrogen breakthrough at CERN

#73
post #6

Earlier quoted context omitted.

If you can electromagnetically trap enough antimatter to use it as fuel you could as well trap a miniature charged black hole that can be fed regular matter to produce power, which skips the whole inefficient part of making antimatter.

Miniature black holes would just evaporate. Antimatter wouldn't.

That's the point, evaporation turns matter into energy. You can tune power by chosing mass of the black hole and then feed it regular matter at a steady rate.

Re: Physicists drive antihydrogen breakthrough at CERN

#74

Earlier quoted context omitted.

> it's mind boggling that overwhelming majority is it though? I mean literally everything has to start there and the only way get to heavier elements is via stars and many-many iterations. it's not like heavier things popped into existence.... or did they...

Yes, it's a little mind boggling because the typical human context is this rocky ball of what is ultimately a very uncommon distribution of heavy elements. It's a strange feeling to know that almost everything is utterly unlike the everyday human experience. If you turn down the uhm acksshuwlly a few notches I think parent post's point is quite obvious.

The average density of matter in the universe is one proton per five cubic meters or so. We're very much the outlier!

Re: Physicists drive antihydrogen breakthrough at CERN

#75
post #51
post #6

Earlier quoted context omitted.

If you can electromagnetically trap enough antimatter to use it as fuel you could as well trap a miniature charged black hole that can be fed regular matter to produce power, which skips the whole inefficient part of making antimatter.

We know how to make antimatter and have actually done it. We have no realistic way to obtain a black hole of any size.

If you can create enough AM to last a space voyage you certainly know how to build big enough particle accelerators.

Re: Physicists drive antihydrogen breakthrough at CERN

#78

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They made a movie about this. It didn’t end so well for the crew.

I admit to invoking the phrase “Where we’re going, we won’t need eyes to see” at least once a year when something feels like it’s going horribly wrong.

But it was one hell of a ride! ;-)

Re: Physicists drive antihydrogen breakthrough at CERN

#79

Earlier quoted context omitted.

> it's mind boggling that overwhelming majority is it though? I mean literally everything has to start there and the only way get to heavier elements is via stars and many-many iterations. it's not like heavier things popped into existence.... or did they...

Yes, it's a little mind boggling because the typical human context is this rocky ball of what is ultimately a very uncommon distribution of heavy elements. It's a strange feeling to know that almost everything is utterly unlike the everyday human experience. If you turn down the uhm acksshuwlly a few notches I think parent post's point is quite obvious.

The uniqueness of our state is quite interesting, arguably profound. Sol exists in the so-called "Local Bubble" which is about 1/100 of the average density of the galaxy, probably caused by multiple supernova. It's possible, if not likely, that this has helped reduce impact events such that life has only reset ~6 times rather than hundreds, and probably contributed to the relative abundance of heavy elements in our solar system.

Earth's biosphere is profoundly 'lucky' on several very disparate time-scales. And then there's the size of the moon...

Re: Physicists drive antihydrogen breakthrough at CERN

#80

Earlier quoted context omitted.

For those who are time-rich and knowledge-poor: https://youtube.com/watch?v=i6jMnz6nlkw (Angela is genuinely a great science communicator and that video is time well spent if you are interested in this topic.)

You can skip the first 42 minutes that are about how bad is an article titled "how antimatter space craft will work". This part is absolutely boring as hell !

But also relevant to the topic…
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