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Physicists drive antihydrogen breakthrough at CERN

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Re: Physicists drive antihydrogen breakthrough at CERN

#21

Post by modeless »

einpoklum wrote: post #19
modeless wrote: post #3

This piece argues that antimatter could be feasible for space propulsion and we could start developing it now: https://news.ycombinator.com/item?id=46073414

What's the key point regarding how we would get a bajillion times more anti-matter than we can now generate, and without expending all the energy we now expend on getting it?

His point seems to be that we haven't yet seriously tried optimizing for energy efficiency of producing antimatter. It's a call to action. If we actually tried it's plausible that we could get to a level that, while still fantastically inefficient in an absolute sense, would still be worthwhile for spaceflight propulsion, where energy density is vitally important. As far as I know, antimatter is the most energy dense fuel possible in known physics by many orders of magnitude.

Also he proposes a few ways that antimatter could be practically used for propulsion, including as a catalyst for fission which seems interesting.

Re: Physicists drive antihydrogen breakthrough at CERN

#22

Post by fooker »

jjmarr wrote: post #15
fooker wrote: post #12

Earlier quoted context omitted.

Not before efficiently converting a large amount of mass into usable energy.

But you want that to happen in space and to control the output of energy. Otherwise you just have a bomb.

The difference between a bomb and a reactor is just clever engineering.

Re: Physicists drive antihydrogen breakthrough at CERN

#23

Post by fooker »

GenerWork wrote: post #14
fooker wrote: post #12

Earlier quoted context omitted.

Not before efficiently converting a large amount of mass into usable energy.

How could we harness this energy and make it usable?

If I knew that, I'd probably have more important things to do than comment it here.

Re: Physicists drive antihydrogen breakthrough at CERN

#24

Post by aeve890 »

impossiblefork wrote: post #8
IsTom wrote: 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.

Minor nit-pick but Hawking Radiation hasn't been observed and remains a theoretical prediction.

Re: Physicists drive antihydrogen breakthrough at CERN

#25

Post by manphone »

andrewflnr wrote: post #10
vkou wrote: post #9

Earlier quoted context omitted.

> a miniature charged black hole that can be fed regular matter to produce power, What form of power and through what principle?

Hawking radiation, I think. Yes, this is at best speculatively feasible.

Probably more like a water wheel - matter spinning around the hole can be accelerated.

Re: Physicists drive antihydrogen breakthrough at CERN

#27

Post by pfdietz »

modeless wrote: post #3

This piece argues that antimatter could be feasible for space propulsion and we could start developing it now: https://news.ycombinator.com/item?id=46073414

Before we get too excited, this current "breakthrough" is making less than 1 antihydrogen atom per second. This corresponds to a delivered annihilation power of less than 1 nanowatt.

Re: Physicists drive antihydrogen breakthrough at CERN

#28

Post by gavinmckenzie »

galacticaactual wrote: post #20
IsTom wrote: 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.

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.

Re: Physicists drive antihydrogen breakthrough at CERN

#29

Post by Qem »

manphone wrote: post #25
andrewflnr wrote: post #10

Earlier quoted context omitted.

Hawking radiation, I think. Yes, this is at best speculatively feasible.

Probably more like a water wheel - matter spinning around the hole can be accelerated.

A spacecraft carrying a blackhole as propulsion means probably would have poor power to weight ratio.

Re: Physicists drive antihydrogen breakthrough at CERN

#30

Post by irjustin »

teleforce wrote: post #26

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.

> 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...

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