Boffins create tabletop ANTIMATTER GUN It generally takes a decent-sized particle accelerator to produce antimatter, but a team of physicists working at the University of Michigan says they've developed a table-top system that can create short bursts of positrons – anti-electrons. Their metre-long device creates electron-positron pairs by firing a petawatt laser at …
Oh, good grief!
The size of the bang depends entirely on how much anti-matter you have. Given it takes an inordinate amount of energy to generate a miniscule amount of antimatter then getting even a decent size 'pop' will probably bankrupt us.
Given that it takes a lot more energy to make the antimatter than you get out of it annihilating, you're not likely to see an antimatter reactor ever.
If you have unlimited energy to spare, antimatter could make a very intense energy _store_, but it will never be an energy _source_. Coal and uranium work for that purpose because you can just dig them out of the ground - if you had to make them yourself first it would be a different story ;)
@Alan
Not sure your analogy stands up. According to the article there are naturally occuring sources of antimatter - all we have to do is build an interstellar starship to collect them and hey presto! Antimatter Reactor.
"all we have to do is build an interstellar starship"
Why bother? Just stop off at Jupiter and capture what is stuck in its magnetic fields. One could do it in Earth orbit too, but Jupiter has a much stronger and larger field, hence captures more.
"The laser itself would do a pretty good job of that..."
It's only 20J per pulse so the 'owners' say that it would give you a nasty burn which would likely make you jump out of the way of the next pulse.
True enough, indeed, that Teflon seems to have fared quite well. :)
Still, it'd be really handy to physicists if they could generate a gram of positrons and store them safely.
Safely, as unsafely would rather render their building unusable.
"I knew Teflon was good, but preventing matter-antimatter annihilation ? "
Not at all. A bunch of electrons were annihilated and a couple of photons of gamma radiation were released 180 degrees from one another.
Low enough radiation to be harmless.
Except with that guy who was next to it and started growing and turning green...
Now we have an antimatter source, someone needs to invent dilithium.
On the flip side it might be possible to use antimatter to catalyse conventional "hot" fusion by supercharging the reaction in a tokamak or more feasibly, a whiffle ball aka Bussard Polywell.
Any problems with containment could be overcome by operating the fusor in pulsed mode with burn times in the 200ms range rather than continuous like the proposed "light bulb" reactor.
If this actually works I propose that it be called the "Impulse Drive".
Now we have an antimatter source, someone needs to invent dilithium.
This is a positron source, not quite as useful as an antiproton source. Given one of those, though, you wouldn't need any dilithium.
It is possible to make relatively lightweight and quite powerful antimatter-catalysed nuclear pulse engine with equipment we could conceivably build right now... have a look at this stuff, especially "Antiproton-catalyzed microfission/fusion propulsion systems". 30 day trip to Mars, a little over 50% of the ship's total mass needed for reaction mass, and all this with a mere 150 nanograms of antiprotons. I bet CERN could brew that much up in under a year, if they really tried hard.
All that's lacking is determination. The US could build such a spacecraft and has some domestic particle accellerators to provide the fuel, but I don't see any US government seriously diverting funds from the military to spaceflight any time soon.
"It is possible to make relatively lightweight and quite powerful antimatter-catalysed nuclear pulse engine ..."
I seem to recall some theory on meson catalyzed fusion devices as well.
As for "the US could build such a spacecraft", erm, not quite. Our rockets still occasionally go awry. It would be rather unpleasant if we have a few hundred kilograms of antimatter depart containment inside of the Earth's magnetosphere, let alone atmosphere. Add in the fact that even gram quantities would cost more than the entire US DoD budget, counting black budgets, I don't see that happening (not to mention building so many particle accelerators) not only anytime soon, but ever.
"Where's the kaboom? There should've been an Earth shattering kaboom!"
<SRB failure, uncontrolled descent of the spacecraft>
"Oh, there it is."
"We are talking Americans, have you seen the size of the tables needed to house some of those fat arses??"
Here in the civilized world of the US (OK, occasionally civilized, when not arguing about gun control, religion or politics), we don't sit on our tables. We sit with the table in front of us.
Hence, the table fails to house anyone.
It is used to hold food though, such as a full sized 23 pound turkey sandwich... ;)
And a few three liter bottles of Coke. :/
<Caveat, I personally don't drink soft drinks, well, not unless there is an ample amount of distilled alcoholic beverage available to decontaminate it.>
Reading the article and its mention of the jets that fire out of a black hole's poles got me thinking.
If a lab on Earth using magnets can so easily divert the course of these jets, what is going on at the black hole, which seems to have no influence on the jets, when all else including light is trapped for eternity.
Well, without an Higgs particle, the jets are no longer influenced by gravity, or with an anti Higgs particle they will race away.
I'm ready for an education, if anyone is up to the challenge.
It's the magnetic fields around the black hole that create the jets. And magnetic fields are themselves "made" of "light" - so are slowly sucked into the black hole. Which in turn means black holes could be "magnets" themselves (unlikely in practice though).
It's really hard to get things to fall into a black hole. Basically if you chuck a rock at a black hole it'll end up orbiting around the hole unless you are very accurate, things in space really like to go into orbits around each other. In order to get to a lower orbit you need to 'lose' some energy and for a black hole that means a LOT of energy.
For an active black hole you end up with a rotating disc of matter, mostly in the form of super-heated plasma. This creates magnetic fields which also get twisted up as the whole lot rotates around, these then funnel the highest energy particles (the hottest and fastest) towards the 'poles' and then out along two beams or jets. Sort of opposite to the earth where solar wind particles are funnelled in at the poles.
This effect along with emitted photons in the form of infra-red, light, X-rays and so on robs the system of some energy allowing the slowest particles to get in a bit closer and eventually disappear beyond the event horizon.
The main point here is the particles in the jets are escaping BEFORE they get to the event horizon, the higgs boson is not required. Indeed by having mass and high velocity they take a nice lot of energy with them as they go.
Phew!
Lets hope that Moore's Law applies to nuclear physics as well as semiconductors.
So by say April 4th, 2063 the technology for a portable antimatter generator ought to fit nicely into say a Minuteman missile upper stage, along with the solar panels (for broadcast power) and superconducting warp nacelles.
Shame I'll be like 89 by then
Really long Kickstarter anyone? (g)
AC/DC 6EQUJ5
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