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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

#161

Post by estimator7292 »

mikewarot wrote: post #157

I wonder what would happen if you had a solid piece of antimatter, say a gram of anti-iron... and just set it down. Would it really annihaliate immediately on contact with air, a lab table, or anything... or would the normal forces that keep us from falling through things still be in effect? Either nothing would happen, or like molten salt in water, the joule currents would be instant and drive it all to go boom in a…

The charges are inverted, so anti-protons are actively attracted to protons.

It would immediately explode.

Re: Antimatter has been transported for the first time

#162

Post by munchler »

estimator7292 wrote: post #161
mikewarot wrote: post #157

I wonder what would happen if you had a solid piece of antimatter, say a gram of anti-iron... and just set it down. Would it really annihaliate immediately on contact with air, a lab table, or anything... or would the normal forces that keep us from falling through things still be in effect? Either nothing would happen, or like molten salt in water, the joule currents would be instant and drive it all to go boom in a…

The charges are inverted, so anti-protons are actively attracted to protons. It would immediately explode.

I think OP is proposing a lump of antimatter with no net electric charge.

My guess is that even in this case the lump’s positrons would immediately interact with the table’s electrons and explode.

Re: Antimatter has been transported for the first time

#163

Post by estimator7292 »

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?

I don't like antimatter because it's the most volatile fuel possible. If power is ever interrupted for any reason for any amount of time, the entire mass explodes.

A slightly less insane fuel source is a micro black hole. Drag a tiny black hole behind your ship and drip-feed it any kind of mass you come across. You still get >90% mass-energy efficiency which is far beyond anything else we know of.

Besides, one of the big problems with antimatter is that it's a battery, not a fuel source. We must first collect the unimaginable amount of energy and then process it into antimatter one particle at a time. If you build a ton of factories around a star you can get meaningful production. But a black hole drive can suck up interstellar gas or any asteroids you come across. Matter is easy to get. Don't ask where the micro black hole comes from.

Re: Antimatter has been transported for the first time

#164

Post by TheSpiceIsLife »

Tadpole9181 wrote: post #93
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…

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 en…

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Re: Antimatter has been transported for the first time

#165

Post by TheSpiceIsLife »

Tadpole9181 wrote: post #136
SoftTalker wrote: post #124

Earlier quoted context omitted.

Any compressed gas fuel is inherently dangerous. There's a video of a CNG-fueled bus falling off a lift and sending a fireball through the maintenance facility. Batteries have some of these same risks: they store a lot of energy and it can be released very quickly under the wrong circumstances.

Which is why we generally don't use highly volatile fuels in vehicles, like I just said? And, no, batteries can have outbursts but they're nowhere near as catastrophic as compressed, explosive gases or an antimatter bomb .

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Re: Antimatter has been transported for the first time

#166

Post by micw »

antonvs wrote: post #99
micw wrote: post #98

Earlier quoted context omitted.

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.

You can throw matter on it. But this needs to be confined carefully...

Re: Antimatter has been transported for the first time

#167

Post by accrual »

stevenalowe wrote: post #119

Unclear on the size of the apparatus require to secure the 92 anti-protons - did it occupy the entire truck?

There's a photo towards the end which shows the equipment in the truck, it seems to be about the size of a mini fridge or a half rack.

Re: Antimatter has been transported for the first time

#168

Post by saalweachter »

M95D wrote: post #81
d--b wrote: post #56

Every time I read one of these, I am amazed by how much stuff superconductivity allows, and how limited we are because it needs ultra low temperatures.

The disadvantages of water-based life.

So it's hard to imagine biological life (chemical life?) without water or carbon, since they're such good solvents and building blocks, but we can at least imagine electronic or mechanical life which don't require them.

But what you can't get away from is heat dissipation.

Any life will use energy will generate heat will need to dissipate heat to maintain homeostasis.

Could you dissipate enough heat to exist at Are there naturally occurring pools of liquid helium out there in the universe, maintained by natural processes, or are you left with vacuum relying on radiative cooling?

Re: Antimatter has been transported for the first time

#170

Post by jffry »

stevenalowe wrote: post #119

Unclear on the size of the apparatus require to secure the 92 anti-protons - did it occupy the entire truck?

Nope, it's pretty compact. The first image in CERN's photo gallery shows it being loaded into that truck: https://cds.cern.ch/record/2957407?ln=en

Of course, it's compact because it only has to last so long. CERN's press release discusses needing a generator and a cryocooler in the truck for longer trips: https://home.cern/news/press-release/experiments/base-experi...

This older article about the test they did with ordinary protons, indicates the outer frame measures "2.00 meters in length, 0.87 meters in width, and 1.85 meters in height" and comes in under 1000kg https://ep-news.web.cern.ch/content/cerns-base-step-leap-for...

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