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Anti-Matter Created By Laser At Livermore
zootropole alerts us to a press release issued today by Lawrence Livermore National Laboratory, announcing the production of 'billions of particles of anti-matter.' "Take a gold sample the size of the head of a push pin, shoot a laser through it, and suddenly more than 100 billion particles of anti-matter appear. The anti-matter, also known as positrons, shoots out of the target in a cone-shaped plasma 'jet.' This new ability to create a large number of positrons in a small laboratory opens the door to several fresh avenues of anti-matter research, including an understanding of the physics underlying various astrophysical phenomena such as black holes and gamma ray bursts." The press release doesn't characterize the laser used in this experiment, but it may have been this one.
Does anyone know how much energy this takes? They mentioned the previous petawatt laser experiment that was decommissioned, but I didn't see where it mentioend the power required for this experiment. If the laser guess by kdawson is correct, we could be looking at a mere 400 joules per 1E11 positrons. Which (if I'm not mistaken) would be an unheard of efficiency for creating antimatter! (Can someone verify? My brain is fried at the moment.)
What I find interesting is that this level of production is competitive with Fermilab. Even if they ran this twice an hour, they'd handily meet or outstrip Fermilab production.
Even more interesting is the possibility for mass manufacture of antimatter. By using mass-produced gold targets, you could rotate the materials in and out of the machine every few seconds, creating previously unseen amounts of antimatter. Such a process could easily provide materials for an antimatter catalyzed fission drive. Possibly even enough to power new forms of interplanetary propulsion.
Am I the only one who's getting really excited about this? /dreamer
Javascript + Nintendo DSi = DSiCade
I always wondered if they could assemble enough anti-matter to perform a Cavendish experiment if it would prove to be repulsive to regular matter gravitationally. I know the current theory doesn't call for it, but hey, that's why we do the experiments. Very symmetrical (in comparison to the electrostatic force equation), and very cool, if it turned out to be true. On the other hand, somebody should stop these fools now. The next thing they will want to do is bottle the stuff, and regular nukes would be toys in comparison.
This may open the possibility of cheaper PET scans. Currently, the limitation of PET scans is the answer to this question: "How far away is the nearest Cyclotron?" The half life of the radioactive material used in Positron Emission Tomography, typically Flourine-18, is ~110 minutes. With a laser that can generate positrons, you could have a mobile PET scan unit that would only need to rely on being able to connect to the grid.
BTM
That was the turning point of my life--I went from negative zero to positive zero.
It's even more amazing when you consider that when lasers were first developed, no one thought they would have much practical use. They were "A solution looking for a problem."
http://www.press.uchicago.edu/Misc/Chicago/284158_townes.html
Now, try to imagine modern technology without lasers...
of a pinhead? I know making gold nano-particles can be done by anyone, anywhere. It is very simple to do. They are much smaller than a pinhead and their arrangement can easily be made so that the surface area is billions of times larger than a pinhead. Now, can a simple pointer laser set off positrons? If not, how about a green laser? If not, how about shining the green laser through a $600 frequency doubler crystal onto those gold nano-particles?
You can't generate a net positive energy source with antimatter. Best you can hope for is to use the antimatter as a form of energy storage (think battery, fuel, etc). Of course, storage problems make it impractical for nearly every use, so don't expect anti-matter cars... ever. Space travel, however, would greatly benefit from a decent means of generating antimatter, since fuel mass trumps most other concerns in that field and anti-matter provides the most thrust/mass of any theoretical substance.
You produce anti-matter in anti-matter-matter pairs. Ergo your idea can not work.
I spent a while thinking if you could exploit the W boson which produces anti-matter - matter pairs of different flavour but I couldnt think of a way. Regardless any way which somebody could come up with would give such a small theoretical energy gain that you would almost certainly lose it through efficiency loses.
Of course, lasers might not be the most energy efficient way of creating antimatter but that doesn't change the fact that if you want to turn m matter into antimatter you will need at least 2*mc^2 energy (at least that's my intuitive guess).
According to my intuition, your intuition is in error. Even if we're creating the antimatter from whole cloth we would be spending:
mc^2 + processing inefficiencies
But during the annihilation, a matter particle is also annihilated producing:
2 mc^2 - processing inefficiencies
Thus, the total released energy is something along the lines of:
mc^2 - 2 * processing inefficiencies
Whether or not we can develop a process where the second part of the equation doesn't dominate (that doesn't go on to level the city) is the real question.
Can I have your babies? Or vice versa? Either would be cool.
I heard on TV that an omnipotent sky monkey plans to torture us all in a volcano forever because some woman made out of a guy's rib ate a snack with a talking snake.
And that was supposed to be an education show!