Anti-Matter Created By Laser At Livermore 465
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.
Re:Holy Mackerel! (Score:5, Insightful)
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.
If true, this is the 1940s all over again -- only on a larger scale. A thimbleful of antimatter would make any H-bomb look like a popgun. (...and yeah, I know we're not yet talking about anywhere near that order of magnitude. Yet.) It would certainly help with space exploration -- but we humans can't even be completely trusted with gunpowder and jet airplanes yet. *sigh*
Re:Holy Mackerel! (Score:5, Insightful)
Why is everyone so hung up on an energy-positive reaction? Antimatter is the ultimate in fuel for space-propulsion as it produces the highest theoretical amount of energy for the least possible mass. (i.e. 100% conversion - losses to nuetrinos that cannot be captured) This plays well into the rocket formula, giving antimatter drives a specific impulse unattainable with other rocket methodologies. In fact, the far-flung future may see c-ships [fourmilab.ch] traveling the stars based on matter-antimatter drives.
What I want verified is not if this process is energy efficient or not. I want to know if this process is several orders of magnitude more efficient than the current Fermilab and CERN processes.
Once again, antimatter catalyzation makes the fuel more efficient for its weight and thus plays well into the rocket formula.
Re:Holy Mackerel! (Score:5, Insightful)
Not really. We've already done the whole Cold War/Mutually Assured Destruction thing. Our weapons are already far, far larger than we could ever deploy here on Earth. Making them that much bigger only makes them that much more useless. At best, the only real advantage would be that they could be scaled down.
Until we start looking at warfare on an interplanetary or interstellar scale, our existing nukes and possible antimatter warheads are going to sit in their silos and go unused. Or in the case of antimatter bombs, I simply hope they're not built. The idea of a large-scale antimatter warhead being prevented from detonation by mere magnetic fields maintained by the nearest power plant is not an appealing idea. Just disrupt the power infrastructure for long enough and we'll blow ourselves to kingdom come. :-/
Re:Holy Mackerel! (Score:4, Insightful)
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.
The great thing about this for spaceflight isn't that it takes a lot or a little to produce antimatter, but rather that the density of usable energy is orders upon orders of magnitude greater than chemical or electric rockets. Denser energy leads to more fuel carried leads to greater delta v leads to semi-relativist flight leads to hate leads to suffering. These can even be used within the atmosphere to launch rockets from the ground easier than you can say "prompt gamma ray output".
Quick question for anyone with the knowledge (Score:5, Insightful)
Does anyone know if this might someday lead to antimatter plants? From a special on discovery, I heard that antimatter has a 100% mass to energy conversion, and uranium/plutonium is very expensive to enrich, so using gold for energy wouldn't be too impractical. This would be very exciting research if it does mean cheap energy at that scale with no pollution.
Re:Quick question for anyone with the knowledge (Score:5, Insightful)
No. While antimatter may have a 100% mass to energy conversion, it takes more energy to create it than it gives off.
Re:Holy Mackerel! (Score:3, Insightful)
Which eventually lead to the solution of bankrupting the USSR. (Something which would have eventually happened anyway, just much slower.)
Or, to be exact, it didn't happen [slashdot.org].
Re:Quick question for anyone with the knowledge (Score:2, Insightful)
I don't necessarily think you are wrong here, but I have a doubt. The reason why is that you wouldn't necessarily be "gaining" energy if you got more out than you put in, because you are simply releasing the energy of the destroyed mass.
As long as the energy required to create the positrons is less than MC^2 (and I would imagine it would be) since anti-matter/matter has a approximate 100% mass to energy conversion, then there should be a net "gain".
Once again, I don't there energy is being "created" here, but more that the energy of the destroy matter is being released.
Similar to how nuclear bombs can produce many many megatons of explosive power from a small catalyst. That too is just releasing the energy in the mass.
Now, making anywhere near efficient use of this energy in anything besides an explosion (bomb/rockets) is another and very important issue.
Russia (Score:2, Insightful)
Russia did not invade Vietnam. The United States invaded Vietnam because it is an historically paranoid state, and feared that communism would takeover east Asia were the grass roots movements of communists not exterminated. Similarly today, we're fighting them "over there" instead of "over here." It's just the manufacture of an enemy image that every government uses to maintain power.
Hell, when it comes down to it, why not let the Cubans take over Florida. After all if you stop them there's a risk of nuclear war.
Are you really afraid of the Cuban army? Really?
The Russians placed those missiles in Cuba because we placed missiles very close to their own borders. They made the mistake of thinking that it was okay to follow our lead.
And people in Florida would much rather live in peace under communism than die in a war.
What if you were right? Would you let any democratic principles get in the way of your own abject idealism?
Once the commies take over there will be peace.
Oh no! The commies! The reds, pinkos, the socialists! Run for your lives! Seriously. Only an insane person can turn cowardice into a call to arms.
After all, absolutely no one died in Russia or China or Cambodia after the Communist victory when they decided to get rid of their enemies.
And how many slaves and Native Americans did we kill in the last 200 years when we wanted to get rid of them? How many Vietnamese died before 1975 and after? How many dictatorships have we sponsored with our money and military technology?
You may not think there is blood on our hands, but we have plenty. I know you desperately want to get to the death toll numbers in your rebuttal, but imperialism and colonialism still take the cake for human misery. And if you don't think that America is an imperial empire... well. We have 700 military bases in almost every country of the world, and outspend the rest of the world in military expenditures. What else could I say.
Re:Holy Mackerel! (Score:3, Insightful)
To say nukes were only used once or twice is terribly misleading. Nukes were only used in a military capacity twice. Even more accurately, they were only used in a military capacity against strategic targets twice. They've been used for political posturing and military advancement approximately 2,000 times [wikipedia.org] in various settings and with varied payloads.
This isn't intended to devalue the magnitude of the decision to effectively annihilate large numbers of human populations or suggest that testing is necessarily equivalent, just to remind you that the tactical application of nuclear weapons is not the only undesirable consequence of developing, distributing, and maintaining those weapons. Even unused nukes have serious consequences to the well being of humans and ecosystems in general.
The display of force in Hiroshima and Nagasaki demonstrated that the weapons were too morally reprehensible to use against human targets. The militarization of the United States and other nations has prevented critical assessment of the relative danger of these weapons from being reflected in policy until fairly recently. Check the graph on that wiki. Does it seem as if people suddenly became aware of the danger of nukes in 1945, or merely their effectiveness? And I'm not even getting into the tailings piles, superfund sites, government payouts to victims of testing, and so on.
Pedantic? Try having a complete thought before accusing someone of pedantry. There are more things going on here than the dramatic end of people's lives or your fantasies about interstellar warfare.
Re:that's not true, theoretically (Score:3, Insightful)
Re:Quick question for anyone with the knowledge (Score:1, Insightful)
Don't you mean less than 2MC^2? Since only 1/2 of the annihilated matter is -anti...
Re:Russia (Score:1, Insightful)
Just remember one very fucking important point in that statement of yours..... Americans ARE NOT PART OF IT. It is the elite and corporate interests that *own* America and it's citizens that act in such a way.
American citizens are just another colony of oppressed people that belong to this "American Imperial Empire" that you speak of. Americans in general have no interests in controlling the rest of the world militarily or economically. Most citizens are far more concerned about the distractions like American Idol, Heroes, Paris Hilton, and Cheeseburgers loaded with chemical crap and zero nutrients. Those of us that tend to concern ourselves with the bigger picture and are consigned to the hell of having a modicum of intelligence are not interested in this Imperial Empire either. I don't mean that as arrogant as it sounds either.
It takes a special kind of person with certain traits and dispositions to cruelly exploit another race of people for their own gain. The average American does not possess those traits and *does not* understand, or perversely enjoy the fact, that buying certain products often helps perpetuate such exploitation in other parts of the world.
Once again, WHO wanted to get rid of them? The average person in those times simply lacked the ability to relate to Native Americans and come to an understanding. The greatest atrocities did not occur from regular people, but from our very own government, corporate interests, and military.
You might as well be saying that all the Chinese workers that participated in building the Great Wall of China actually *wanted* to build it in the first place!
"Great Heavens! That's a laser!" (Score:3, Insightful)
Re:Holy Mackerel! (Score:1, Insightful)
You seem to be ignoring Israel already having nuclear weapons. And considering past behaviour, they're more likely to pull off a nuclear first strike than Iran would, should the latter ever get nuclear weapons.
Re:Quick question for anyone with the knowledge (Score:5, Insightful)
Make hydrogen containers with very thin gold walls - or more likely frozen pellets coated with gold. Bombard the gold with a laser, turning the surface layer into antimatter. Antimatter annihilates with the matter below it and creates an explosion, which heats and compresses the hydrogen, igniting a fusion reaction.
It is, essentially, the equivalent of a fission-initiated fusion, which is proven to work and work well. The difference is that there's no lower bound to the size of an antimatter explosion - even a single electron and positron annihilate - so you can make the explosion be of suitable size for a power plant. And of course annihilation, as the name implies, doesn't leave behind radioactive materials, just gamma rays.
Besides, Laser Antimatter Fusion is pretty much the epitome of cool ;).
Re:Quick question for anyone with the knowledge (Score:5, Insightful)
The point is having the ability to produce lots of these particles in a directed manner, capture and store them for further study.
Previously the main source for antimatter was certain types of radioactive decay and nuclear reactions.
(example: if you go to the hospital for PET imaging - they inject you with radioactive material that decays by emitting anti-electrons = positrons)
If you want something that could potentially produce energy, this is not it - although in studying the process and the particles we might eventually learn how to produce antimatter more efficiently (to store energy) or perhaps even with net gain by inducing some sort of nuclear reaction.
Magnetic containment won't work (Score:3, Insightful)
Of course, if you made do with neutral antimatter you could clump it together, but then your magnetic containment won't work.
Re:Holy Mackerel! (Score:3, Insightful)
Twice?
For the record, we've dropped nuclear bombs on four countries.
Japan, Spain, US, Greenland.
Not all of them were on purpose, but that doesn't mean they weren't dropped.
http://en.wikipedia.org/wiki/List_of_military_nuclear_accidents [wikipedia.org]
Three of the four countries still have radioactive material on the ground from them. And they just couldn't find it in Greenland.
Re:Holy Mackerel! (Score:2, Insightful)
Which raised the (very legitimate) question of why we were even in the conflict to begin with.
You should probably start your quest for answers with the French.
Re:Holy Mackerel! (Score:3, Insightful)
You're using the wrong calorie. Should be roughly 2.8 kg. Here's the calculation:
1 ton TNT == 4.184*10^9 J
mass equivalent m = 60 megatons TNT/c^2 = 2.5104*10^17 J / (9*10^16 m^2/s^2) ~ 2.8 kg.
It's commonly misunderstood just how much mass in a nuclear bomb is converted to energy.
Re:Holy Mackerel! (Score:3, Insightful)
Umm, all the time frames were quoted as from the point of view of the guy on the rocket.
He never said the rocket was traveling faster than light.
Re:Holy Mackerel! (Score:4, Insightful)
> you didn't account at all for relativistic effects at all.
It fully takes into account SR effects.
> A big question is how come you can travel faster than light
It doesn't. All times as for the people in the spaceship, as I stated. The reason it takes less time is because of time dilation.
> when you get to Vega everyone who sent you will be long dead.
Indeed.
Re:Holy Mackerel! (Score:5, Insightful)
Time dilation and distance contraction. This are special relativity effects.
For the people on earth, the ship takes 4 million years to travel 4 million light years at close to the speed of light. But for people in the rocket, it can be a very short amount of time.
Re:Holy Mackerel! (Score:3, Insightful)
> You left out where the energy to sustain 1 gee is going to come from
I gave the calculations for the energy/mass required to sustain 1g.
> Also with \gamma>>50 the blue shifted microwave background is not looking so nice.....
Shields :-)