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Antimatter has been transported for the first time

nature.com

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Re: Antimatter has been transported for the first time

#91

Post by im3w1l »

teiferer wrote: post #75
amelius wrote: post #62

Earlier quoted context omitted.

> ideal spacecraft fuel If you're ok with the looming threat of total annihilation. I suppose at least it will kill you faster than your neurons can communicate so you wouldn't even notice.

> If you're ok with the looming threat of total annihilation. Don't you have that problem with any energy-dense fuel? It's just that it doesn get more dense than that, so you can be very space and weight efficient. It's like everybody saying that a hydrogen car is a rolling bomb because of the energy stored in the hydrogen. Well, sure, but gasonline has just as much energy stored. Which is the whole point of fuel. To…

Volatility and energy content are not necessarily related.

Re: Antimatter has been transported for the first time

#92

Post by dylan604 »

Rooster61 wrote: post #86
spbaar wrote: post #80

Earlier quoted context omitted.

I make a pasta/antipasta joke every time I'm at an italian resteraunt and no one ever laughs :(

Annihilation of Italian food is nothing to laugh at, and is in fact a tragedy

I thought the entire point of being given a plate of Italian food was to annihilate it, followed by some tiramisu.

Re: Antimatter has been transported for the first time

#93

Post by Tadpole9181 »

teiferer wrote: post #75
amelius wrote: post #62

Earlier quoted context omitted.

> ideal spacecraft fuel If you're ok with the looming threat of total annihilation. I suppose at least it will kill you faster than your neurons can communicate so you wouldn't even notice.

> If you're ok with the looming threat of total annihilation. Don't you have that problem with any energy-dense fuel? It's just that it doesn get more dense than that, so you can be very space and weight efficient. It's like everybody saying that a hydrogen car is a rolling bomb because of the energy stored in the hydrogen. Well, sure, but gasonline has just as much energy stored. Which is the whole point of fuel. To…

Surely you understand there's a difference?

Liquid gasoline does not spontaneously explode like an action movie. You can put a match in the fuel tank and (presuming infinite oxygen availability) it'd just start a small fire. Heck, may even just give a little puff and then put out the match.

Antimatter in any sufficient fuel quantity, the moment it breaks confinement, will completely annihilate and release ALL it's energy in a single moment, setting off a chain reaction to the remaining antimatter. It's like sitting on an armed nuclear bomb, where you rely on electrified, highly sophisticated containment equipment never failing a single time for months to years... In a radiation-heavy environment known for causing sophisticated electronics to have errors.

And, yes, hydrogen cars were looked at critically because of the perception they can Hindenburg (I'm unsure if it's true or not). Which is a good example because you don't particularly see any hydrogen blimps anymore - we made them illegal because they're dangerous.

Re: Antimatter has been transported for the first time

#94

Post by throwaway290 »

aftbit wrote: post #33

How could we make enough antimatter to do something useful? Would we need to go hang out near the sun or deorbit Jupiter's moons with superconducting coils to get enough energy?

The more important question is not could we. it's should we

Re: Antimatter has been transported for the first time

#95

Post by antonvs »

teiferer wrote: post #75
amelius wrote: post #62

Earlier quoted context omitted.

> ideal spacecraft fuel If you're ok with the looming threat of total annihilation. I suppose at least it will kill you faster than your neurons can communicate so you wouldn't even notice.

> If you're ok with the looming threat of total annihilation. Don't you have that problem with any energy-dense fuel? It's just that it doesn get more dense than that, so you can be very space and weight efficient. It's like everybody saying that a hydrogen car is a rolling bomb because of the energy stored in the hydrogen. Well, sure, but gasonline has just as much energy stored. Which is the whole point of fuel. To…

Antimatter is a completely different story.

The difference is that antimatter annihilates with any normal matter that it comes into contact with. This means you can't just put it in a tank, the way you can with hydrogen. You can't e.g. combine it with some metal to make a metal hydride to make it safer to store, the way you can with hydrogen.

At an absolute minimum, you need extremely strong magnetic confinement and an extremely hard vacuum. And even then, you're going to get collisions with stray atoms and annihilation events which release gamma rays and other radiation products - although shielding is probably the least of your worries in this scenario.

A typical research lab at a university or large corporation can't make a vacuum strong enough to store even tiny quantities of antimatter for more than a few minutes, and they can't produce the magnetic confinement strength required to store macro quantities of it, either.

So the question with an antimatter-powered car is not if it's going to destroy the surrounding region and bathe it in hard radiation, but how many milliseconds (or less) it will take before that inevitably happens.

But probably luckily for us, this is all moot, because we have no way of producing enough antimatter for this to be an issue. If all the antimatter that's ever been created by humans annihilated simultaneously, only scientists monitoring their instruments closely enough would notice, because it's such a microscopic amount.

Edit: for perspective, you'd need about 7 billion times the 92 antiprotons transported in the truck in the story to produce the energy produced by a single grain of gunpowder.

Re: Antimatter has been transported for the first time

#96

Post by pfdietz »

csense wrote: post #37

From a layman's point of view antimatter seems like an ideal spacecraft fuel. It's as energy dense as E = mc^2 allows, and if you have infrastructure to make it, the only input you need to produce it is electricity. Being able to transport it seems like an important piece of that puzzle. Production and storage would need to be scaled by many orders of magnitude, but that's merely an engineering problem...right?

The confinement scheme used here is likely a Penning Trap. Such devices are limited in the amount of antimatter they can store by the Brillouin limit. The energy stored will be no more than the magnetic energy of the field of the trap, and so much less than the explosive yield of a mass of TNT (say) equal to the mass of the trap.

https://en.wikipedia.org/wiki/Non-neutral_plasma

Re: Antimatter has been transported for the first time

#97

Post by pfdietz »

bovermyer wrote: post #78
csense wrote: post #37

From a layman's point of view antimatter seems like an ideal spacecraft fuel. It's as energy dense as E = mc^2 allows, and if you have infrastructure to make it, the only input you need to produce it is electricity. Being able to transport it seems like an important piece of that puzzle. Production and storage would need to be scaled by many orders of magnitude, but that's merely an engineering problem...right?

From a layman's point of view, I'm more interested in antimatter's potential as a weapon. Not necessarily because I want to use it, but because I have a vague idea of what it's capable of, and what that would mean in the hands of certain groups capable of producing it.

The big advantage of nuclear weapons is they are very cheap per unit of energy yield. Bang for the buck, if you will.

Antimatter production is so inefficient that they will be much more expensive per unit energy yield.

Re: Antimatter has been transported for the first time

#98

Post by micw »

antonvs wrote: post #95
teiferer wrote: post #75

Earlier quoted context omitted.

> If you're ok with the looming threat of total annihilation. Don't you have that problem with any energy-dense fuel? It's just that it doesn get more dense than that, so you can be very space and weight efficient. It's like everybody saying that a hydrogen car is a rolling bomb because of the energy stored in the hydrogen. Well, sure, but gasonline has just as much energy stored. Which is the whole point of fuel. To…

Antimatter is a completely different story. The difference is that antimatter annihilates with any normal matter that it comes into contact with. This means you can't just put it in a tank, the way you can with hydrogen. You can't e.g. combine it with some metal to make a metal hydride to make it safer to store, the way you can with hydrogen. At an absolute minimum, you need extremely strong magnetic confinement and…

You can easily put it into an antimatter tank ;-)

Re: Antimatter has been transported for the first time

#99

Post by antonvs »

micw wrote: post #98
antonvs wrote: post #95

Earlier quoted context omitted.

Antimatter is a completely different story. The difference is that antimatter annihilates with any normal matter that it comes into contact with. This means you can't just put it in a tank, the way you can with hydrogen. You can't e.g. combine it with some metal to make a metal hydride to make it safer to store, the way you can with hydrogen. At an absolute minimum, you need extremely strong magnetic confinement and…

You can easily put it into an antimatter tank ;-)

Only if you wear antimatter gloves while doing it.

Also, now your tank is just fuel as well.

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