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Scientists Create Di-positronium Molecules

samzenpus posted about 7 years ago | from the super-laser dept.

Science 160

doxology writes "The BBC reports that scientists have been able to create di-positronium molecules. A di-positronium molecule consists of two positronium atoms, exotic atoms which are made from an electron and a positron (the anti-particle of the electron). A potential use of these molecules is to make extremely powerful gamma-ray lasers, possibly on sharks."

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And doxology ruins the whole thread (5, Funny)

BadAnalogyGuy (945258) | about 7 years ago | (#20585869)

Hey! You're supposed to let US make the jokes.

Re:And doxology ruins the whole thread (2, Funny)

smitty_one_each (243267) | about 7 years ago | (#20585963)

doxology [reference.com] : a hymn or form of words containing an ascription of praise to God
Perhaps you meant:
d'enouement [reference.com] : The solution of a mystery; issue; outcome.
Because if we're not about st00p3d jokes, we're about pedantry. ;)

Re:And doxology ruins the whole thread (2, Funny)

BadAnalogyGuy (945258) | about 7 years ago | (#20585979)

No, I didn't make any mistake.

Re:And doxology ruins the whole thread (2, Informative)

johnw (3725) | about 7 years ago | (#20586009)

The original article was posted by someone called "doxology"!

Re:And doxology ruins the whole thread (1)

smitty_one_each (243267) | about 7 years ago | (#20587331)

First day, new eyes. ;)
This pair o' doxology usages recalls the Steven Wright jape:
"When I was a boy, I had a dog named Stay. I'd say 'Come here, Stay! Come here, Stay! He would just look at me...and keep on typing. He was an East German Shepherd. Very, very disciplined."

Not fair! (3, Funny)

hcdejong (561314) | about 7 years ago | (#20585889)

If you're going to include all the applicable memes in the blurb, there'll be nothing left for us to post about.

Re:Not fair! (0)

Oersoep (938754) | about 7 years ago | (#20585929)

Don't worry.
Hitler and his Nazis are here to save the day.

Re:Not fair! (1, Redundant)

Arabani (1127547) | about 7 years ago | (#20585969)

Come on, at least he didn't use the obvious one!

In Soviet Russia sharks put lasers on you!

Re:Not fair! (2, Funny)

morgan_greywolf (835522) | about 7 years ago | (#20586021)

Well, I for one welcome our new gamma-ray laser wearing shark overlords!

Re:Not fair! (1, Funny)

llamalad (12917) | about 7 years ago | (#20586047)

Can you imagine a beowulf cluster of laser sharks?

Re:Not fair! (1, Funny)

Anonymous Coward | about 7 years ago | (#20586085)

Only old people build beowulf clusters of laser sharks in Korea.

Re:Not fair! (1)

llamalad (12917) | about 7 years ago | (#20590187)

Yeah, well, do the beowulf clusters of laser sharks in Korea eat hot grits?

Re:Not fair! (5, Funny)

somersault (912633) | about 7 years ago | (#20586029)

In Soviet Russia, electron is anti-particle of positron!

Re:Not fair! (0, Redundant)

mcmonkey (96054) | about 7 years ago | (#20588143)

In Soviet Russia, electron is anti-particle of positron!

Shouldn't that be....oh, I see what you did there.

Re:Not fair! (2, Funny)

jollyreaper (513215) | about 7 years ago | (#20586033)

If you're going to include all the applicable memes in the blurb, there'll be nothing left for us to post about.
If they can make an anti-oxygen, that means we can have di-positronic monoxide, anti-water! It's got positronolytes, what anti-plants crave.

Re:Not fair! (3, Informative)

Chris Mattern (191822) | about 7 years ago | (#20586321)

Dude, I know you don't read the article, but you should at least read the summary. Positronium isn't anti-hydrogen; it's an electron and a positron, not a positron and an anti-proton.

Chris Mattern

Re:Not fair! (3, Funny)

jollyreaper (513215) | about 7 years ago | (#20587395)

Dude, I know you don't read the article, but you should at least read the summary.
Dude, this is slashdot. We're only half-reading the subject lines.

Re:Not fair! (4, Funny)

Opportunist (166417) | about 7 years ago | (#20586329)

Anti plants? Are you nuts? Anti plants do anti photosynthesis. And while glowing oaks might be cool, their carbon emissions are just way too high.

Re:Not fair! (3, Funny)

jollyreaper (513215) | about 7 years ago | (#20587303)

Anti plants? Are you nuts? Anti plants do anti photosynthesis. And while glowing oaks might be cool, their carbon emissions are just way too high.
Carbon footprints don't matter, my pasta/antepasta reactor will generate all the clean energy we need. Of course, the carb footprint will be a little high but such is the price of progress.

Re:Not fair! (1)

The Yuckinator (898499) | about 7 years ago | (#20588941)

funny funny funny + 1 MILLION funny. thanks for the laugh

Re:Not fair! (1)

Scrameustache (459504) | about 7 years ago | (#20587407)

Anti plants? Are you nuts? Anti plants do anti photosynthesis. And while glowing oaks might be cool, their carbon emissions are just way too high.
You just don't get it do you? Anti-Carbon emissions would solve global warming forever!

Re:Not fair! (1)

McWilde (643703) | about 7 years ago | (#20586347)

How do you figure positronium is anti-hydrogen? You'd need at least an anti-proton in there...

Re:Not fair! (1)

jollyreaper (513215) | about 7 years ago | (#20587355)

How do you figure positronium is anti-hydrogen? You'd need at least an anti-proton in there...
It's faith-based science: I believe one is there, even though I can't see it. Now quit fucking up my joke. :)

Re:Not fair! (1)

at_slashdot (674436) | about 7 years ago | (#20588255)

You must be new here...

Sharks (1)

nlitement (1098451) | about 7 years ago | (#20585903)

Err.. does anyone else wonder why specifically sharks?

Re:Sharks (2, Funny)

TheThiefMaster (992038) | about 7 years ago | (#20585927)

No, we've seen the Austin Powers films.

Re:Sharks (0)

Anonymous Coward | about 7 years ago | (#20585933)

Never watched austin powers have we?

Re:Sharks (5, Informative)

y86 (111726) | about 7 years ago | (#20585945)

Err.. does anyone else wonder why specifically sharks?


Dr. Evil: You know, I have one simple request. And that is to have sharks with frickin' laser beams attached to their heads! Now evidently my cycloptic colleague informs me that that cannot be done. Ah, would you remind me what I pay you people for, honestly? Throw me a bone here! What do we have?

Its an Austin Powers joke. http://www.imdb.com/title/tt0118655/quotes/ [imdb.com]

Re:Sharks (1)

weicco (645927) | about 7 years ago | (#20586119)

Ill-tempered mutated sea bass.

mis-post (0)

Anonymous Coward | about 7 years ago | (#20585907)

should have read "extremely powerful gamma-ray frickin lasers"

Someone get Wheaton in here (5, Funny)

LiquidCoooled (634315) | about 7 years ago | (#20585911)

If ever there was a topic which he could explain it would be this.

Sure they can be mounted on sharks, but... (-1, Redundant)

UnixRevolution (597440) | about 7 years ago | (#20585913)

Can they run linux?

Marvel comics... (1)

Notquitecajun (1073646) | about 7 years ago | (#20585925)

Sweet, one step closer to me getting gamma-induced powers...HULK SMASH....

Re:Marvel comics... (5, Funny)

y86 (111726) | about 7 years ago | (#20586121)

Sweet, one step closer to me getting gamma-induced powers...HULK SMASH....


Or cancer.

Re:Marvel comics... (4, Funny)

Scrameustache (459504) | about 7 years ago | (#20587461)

Sweet, one step closer to me getting gamma-induced powers...HULK SMASH....


Or cancer.
I realized long ago that the Marvel universe is identical to our own except for one fundamental detail: In our universe, when a freak accident occurs, people die. In the Marvel universe, they get super big, super strong, and oddly colored.

Re:Marvel comics... (3, Funny)

Jeek Elemental (976426) | about 7 years ago | (#20589097)

comics in the marvel universe must be pretty depressing, and short.

Re:Marvel comics... (2, Funny)

bentcd (690786) | about 7 years ago | (#20590095)

comics in the marvel universe must be pretty depressing, and short.
No, I think they're rather drawn out and paneful . . .

Re:Marvel comics... (1)

ceoyoyo (59147) | about 7 years ago | (#20588993)

I think one of the lasers he's talking about would bypass cancer and just vaporize nice holes in you.

Re:Marvel comics... (0)

Anonymous Coward | about 7 years ago | (#20589293)

Dr Bruce Banner's application to work on the research team was denied for obvious reasons.

Sorry, they're endangered... (1, Redundant)

Telephone Sanitizer (989116) | about 7 years ago | (#20585951)

Dr. Evil: You know, I have one simple request. And that is to have sharks with frickin' laser beams attached to their heads! Now evidently my cycloptic colleague informs me that that cannot be done. Ah, would you remind me what I pay you people for, honestly? Throw me a bone here! What do we have?

Number Two: Sea Bass.

Dr. Evil: [pause] Right.

Number Two: They're mutated sea bass.

Dr. Evil: Are they ill tempered?

Number Two: Absolutely.

Dr. Evil: Oh well, that's a start.

Possibly on sharks? (4, Funny)

fgaliegue (1137441) | about 7 years ago | (#20585955)

From the end of the summary, the very end in fact:

[...],possibly on sharks Can the author of the news please elaborate? I just don't see how this discovery possibly relates to an undeservedly frowned upon species of fish...

The State of Science Journalism (1, Funny)

Anonymous Coward | about 7 years ago | (#20585971)

'"It's like having a trickle of water filling up a bath and then you empty it out and you get a big flush," said Dr Cassidy.'

TFA fails to confirm whether or not this involved a series of tubes.

Re:The State of Science Journalism (1)

somersault (912633) | about 7 years ago | (#20586051)

I tend to find that my baths don't work well for flushing.. wouldn't a toilet flush have been a better analogy? The plug hole in a bath doesn't drain much faster than the taps fill. Meh.

Re:The State of Science Journalism (2, Funny)

jollyreaper (513215) | about 7 years ago | (#20586065)

'"It's like having a trickle of water filling up a bath and then you empty it out and you get a big flush," said Dr Cassidy.'

TFA fails to confirm whether or not this involved a series of tubes.
I think we need to explain to our tiny scientist the difference between a tub and a toilet. Someone else will have to explain that French thing that shoots water at yer bum.

Re:The State of Science Journalism (3, Funny)

Opportunist (166417) | about 7 years ago | (#20586369)

Whatever, just make sure he knows the difference between the tub and the toilet before you invite him to your next party. Don't ask for details, just trust me on this one.

Re:The State of Science Journalism (2, Funny)

jollyreaper (513215) | about 7 years ago | (#20587237)

Whatever, just make sure he knows the difference between the tub and the toilet before you invite him to your next party. Don't ask for details, just trust me on this one.
Not to mention my poor fish tank...

On the good side (4, Interesting)

Billosaur (927319) | about 7 years ago | (#20586013)

As a result, there is a huge interest in the technology from the military as well as energy researchers who believe the lasers could be used to kick-start nuclear fusion in a reactor.

Well, I'm not sure if letting the military get their hands on it is such a good thing, but the use to initiate nuclear fusion could be the key to cleaner power for everyone. The hardest part of initiating fusion has been pouring enough energy in to start the reaction and allow it to become self-sustaining. This discovery might lead to technology capable of generating the necessary energy.

Re:On the good side (0)

Anonymous Coward | about 7 years ago | (#20586423)

The hardest part of initiating fusion has been pouring enough energy in to start the reaction and allow it to become self-sustaining.
What are you talking about? Lasers would be used for inertial confinement fusion which is not self-sustaining. Nor is it meant to be. It uses pellets which are 'zapped' by the laser, burn up, have some fusion reactions, release their energy, and are then replaced with a new pellet to start the cycle over again.

Tokamak reactors (the self-sustaining ones) don't use lasers to heat the plasma nor would that be the most efficient way to heat the plasma (as compared to X-ray heating or induction heating).

Re:On the good side (2, Insightful)

ducomputergeek (595742) | about 7 years ago | (#20587515)

It will probably be military funding that carries out the research. After all, we've mastered creating an uncontrolled, none contained fusion reaction: please see Hydrogen Bombs, Thermonuclear Weapons, fission-fusion weapons, etc.. The holy grail in Weapons research is the true 4th Generation Thermonuclear bomb that uses some method to trigger the reaction other than a fission weapon. (Personally I like to call them Fusion bombs because most people don't know the difference between a nuclear and thermonuclear reaction...all they hear is "nuclear")

And if you can use this technology to jump start a sustainable fusion reaction for power, you can use it as a trigger in a Thermonuclear weapon. And why would the military like such a weapon? Because it gives you all the power of an Atomic weapon without all the nasty radioactive side effects. A pure Fusion bomb releases a burst of X-ray's and Gamma Rays at the initial detonation, but those don't cause fall out. It is possible the Neutron Flux might cause some elements to turn into radio active isotopes, but this is going to be limited. However you still get all the bang from the resulting over pressure wave followed by the Thermo Radiation (Also known as Heat).

Now you actually have a nuclear weapon that could be deployed tactically, i.e. on the battlefield, without all the baggage of current fission-fusion weapons due to the lack of fallout. Also it would create a bunker buster the ability to destroy bio-chem weapons caches if needed as well. (Not many organisms and chemicals are going to survive that inferno). Again all the bang, none of the radio active fall out problems. So you also then have fusion weapons that will likely be used in combat operations. They would have been useful in places like Tora Bora. (Although the real reason Bin Laden is still alive....the price on his head is what? USD 24M. What is a poor member of the Bin Laden clan worth? $500M? Gee you kill Osama, whether a merc/traitor/or POTUS, you really think there is a place on this planet you can hide from that kind of wealth and power?)

I hereby await the gasps from the slashdot crowd followed by where I got the physics wrong (Sorry the last Physics class I had was AP over a decade ago, so this is to the best of my remembering/understanding)...

Re:On the good side (1)

Alioth (221270) | about 7 years ago | (#20588709)

Gasp! Gasp! GASP!

The fusion reaction in an H-bomb is contained, or it wouldn't occur at all. It's just not contained for very long, that's all. The type of confinement in an H-bomb is called "inertial confinment".

Fission's the same: the nuclear reaction can only take place while the critical mass remains assembled. By the time the nuke is actually destroying stuff (including things as close as the bomb casing), the reaction is already over. Much of a bomb's efficiency is related to how long you can keep the critical mass assembled, or the fusion reaction confined. This is why the Nagasaki bomb was much more powerful than Hiroshima: a better way of keeping the critical mass assembled, leading to more of the fissile material fissioning.

Obligatory (-1, Troll)

phoenixwade (997892) | about 7 years ago | (#20586015)

But even with the with frickin' laser beams attached to their heads, Chuck Norris would kick their asses.... er .... Fins!

My mom was killed by a Sharks from the Soviet Union with frickin' laser beams attached to their heads, before Chuck Norris could kick their asses, you insensitive clod

Can you imagine (5, Funny)

ciaohound (118419) | about 7 years ago | (#20586055)

what would happen if Scotty reversed the polarity on those?

Re:Can you imagine (1)

TheRaven64 (641858) | about 7 years ago | (#20586435)

Instead of having an electron orbiting a positron, you'd have a positron orbiting an electron!

Re:Can you imagine (0)

Anonymous Coward | about 7 years ago | (#20587235)

Since it's a molecule composed of two identical 'atoms,' it must necessarily be non-polar.

Re:Can you imagine (0)

Anonymous Coward | about 7 years ago | (#20587665)

what would happen if Scotty reversed the polarity on those?
I have news for you; 'he's dead, Jim.'

Reversed Polarity ..... (1)

Archangel Michael (180766) | about 7 years ago | (#20588491)

... how quaint

Re:Can you imagine (1)

Steneub (1070216) | about 7 years ago | (#20590003)

Di-electronium of course!

The "optics" of a gamma laser (5, Informative)

Wilson_6500 (896824) | about 7 years ago | (#20586139)

A gamma-ray laser would certainly have many applications. Maybe the energy density is so high that it becomes irrelevant, but the problem that jumps out at me is that you really can't refract high-energy photons. About all you can do is stop them. I don't see this type of "laser" being used in most applications where you traditionally think lasers would be useful, since you wouldn't be able to easily focus these beams, guide them in fiber, or anything like that. The most useful thing you could do with this type of laser, I would guess, would be ablation--THAT it should be pretty darn good at.

Anyhow, it'll be interesting to see the radiometry for these lasers in however many years it'll take for them to be in a position where they can even think about that sort of thing. From that, you can figure out the dosimetry if you were to turn one onto a person. In this situation, a medical linac should be to this sort of thing what a flashlight is to a laser in terms of photon flux. When you're talking about gamma photons instead of visible ones, I imagine you could give someone a pretty serious radiation dose in pretty short order. From a military perspective I don't think that putting that in a hand-held weapon would exactly rival bullets (which are pretty good at disabling people quickly, something that radiation couldn't do reliably barring stupidly high doses over large areas of the brain or GI), especially considering the cost. Putting one on a satellite and blasting ICBMs in orbit, however, could be a very different story--you don't have nearly as much atmosphere to get through, and you ought to be able to put an awful lot more energy in that missile with similar fluxes of gamma photons versus lower-energy photons. The gammas would probably significantly penetrate the housing of the missile, too, which could be good or bad--bad in that it spreads out the heating effect you'd get, good in that you can significantly heat things that are behind a few layers of metal.

Come to think of it, considering that medical linacs have caused serious burns (and then death from ARS) in the past, turning a gamma laser on someone would probably basically burn right through them--so maybe dosimetry really isn't an issue (for the target--for the operators, on the other hand...)

Anyhow, that's way in the future. For now, all we have are jokes about sharks that can turn people into the Hulk from ten meters.

Re:The "optics" of a gamma laser (4, Insightful)

marcosdumay (620877) | about 7 years ago | (#20586479)

"Putting one on a satellite and blasting ICBMs in orbit, however, could be a very different story"

I doubt it. If you can't focus the bean, you don't have much chance of using it at distance.

Re:The "optics" of a gamma laser (2, Insightful)

Overzeetop (214511) | about 7 years ago | (#20586669)

If it's a laser, you don't need to focus it.

Re:The "optics" of a gamma laser (0)

Anonymous Coward | about 7 years ago | (#20588589)

If it's a bean, it's not a laser.

Re:The "optics" of a gamma laser (3, Informative)

Alioth (221270) | about 7 years ago | (#20589057)

It depends. Not all lasers emit a collimated beam without a lens. For example, laser diodes are highly divergent - something like 30 degrees. To get a nice, narrow traditional laser beam with a laser diode, you need a lens.

Now the gamma laser may well be highly collimated without any additional focusing. But we don't know that for a laser that's not been built and is only theoretically posssible!

Re:The "optics" of a gamma laser (4, Informative)

Watson Ladd (955755) | about 7 years ago | (#20587911)

You actually can focus gamma rays [esa.int] .

Re:The "optics" of a gamma laser (0)

Anonymous Coward | about 7 years ago | (#20586763)

Putting one on a satellite and blasting ICBMs in orbit, however, [...]

I'm not very well versed in nuclear weapons, but wouldn't blasting unstable, near-critical mass of fissil material with gamma rays trigger a chain reaction? Just curious.

Re:The "optics" of a gamma laser (2, Insightful)

HaveNoMouth (556104) | about 7 years ago | (#20587145)

...but the problem that jumps out at me is that you really can't refract high-energy photons
Of course you can. All you need is a small black hole.

Re:The "optics" of a gamma laser (1)

NOVADan (1156341) | about 7 years ago | (#20588733)

I would hope this technology would be used in a positive way as in an environmentally friendly energy source...LINK [bbc.co.uk] But it's more likely the military is salivating at the STAR WARS possibilities as mentioned above. An anti-missile defense would be beneficial...or we could make a HULK-SHARK, big, green, and a head full of lasers. novalasers.com [novalasers.com]

gamma-ray annihilation lasers (1)

jovius (974690) | about 7 years ago | (#20586167)

oh yes... that'll do them sharks.

FTFA (1)

ArwynH (883499) | about 7 years ago | (#20586255)

"The discovery, reported in the journal Nature, is a key step in the creation of ultra-powerful lasers known as gamma-ray annihilation lasers."

Gamma-ray annihilation lasers!!! Oh yeah baby! Who says scientists can't think of cool names?!

Re:FTFA (0)

Anonymous Coward | about 7 years ago | (#20587013)

Gamma-Ray AnnihilAtion Lasers.

The Graal of geeks and evil geniuses!

Powering Space Elevators (1)

kieran (20691) | about 7 years ago | (#20586325)

First: "gamma-ray annihilation lasers". Say it out loud. I just want you to take in how immensely cool that sounds.

Second, might these be the trick to powering Space Elevators? Admittedly materials is still the bigger problem there, but beaming power to the platform was always part of the master plan.

Re:Powering Space Elevators (1, Funny)

Anonymous Coward | about 7 years ago | (#20587257)

gamma-ray annihilation laser can punch a hole in just about anything, but appears to be good for nothing else.

Still, its good to know that the search for the Holey GRAYL continues.

Re:Powering Space Elevators (1)

ceoyoyo (59147) | about 7 years ago | (#20589143)

No. Creating antimatter is an incredibly inefficient process. The reason it's called a gamma ray ANNIHILATION laser isn't because of what happens to whatever it's aimed at, it's because the laser powers itself by annihilation and probably destroys itself in the process. So you only get one shot. Then you have to go make more antimatter.

non-shark-related (2, Insightful)

sexybomber (740588) | about 7 years ago | (#20586475)

I read the article and I still don't get it. How can these positronium atoms possibly be stable? TFA says that they've "merged an electron and a positron", which is impossible, because when the electron and the positron touch, there's a relatively large explosion.

So ... one of the particles has to be orbiting the other, like a regular atom. But wouldn't it blow up just the same if, say, a stray cosmic ray or a neutrino or something were to smack the nucleus? IIRC, photons are more like normal matter than antimatter.

Any particle physicists in the house who want to enlighten us?

Re:non-shark-related (1, Insightful)

Anonymous Coward | about 7 years ago | (#20586661)

IANAPP, but TFA specifically refers to positronium atoms as "short-lived", and notes that the molecules survived for "just a quarter of a nanosecond".

Re:non-shark-related (4, Informative)

Ecuador (740021) | about 7 years ago | (#20587467)

First of all, the electrons orbiting around the atom's nucleus is an atomic model that was valid during the first couple of decades of the 20th century. Our atomic models of the last 80 years are not as simple as that.
You are right about the electron and the positron being able to annihilate each other (producing a couple of photons IIRC, I guess your "explosion" of radiation). However, you are limited to high school level (particles orbiting each other) and Hollywood level (matter-antimater explosions) physics, but you are getting in quantum physics territory, where the particle-antiparticle annihilation does not exactly happen when the particles "touch". In fact we cannot even say that two particles "touch" in the traditional sense of the word.
Anyway, without being a particle physicist and without RTFA (leaving for work now), I can tell you that I don't see a reason that a positron-electron pair could not survive for a brief time. Where "brief" in physics is measured in ps or at least ns. When you hear physics news like "we created the xxx exotic particle" they are usually referring to something that existed in their accellerator for a picosecond or so...

Re:non-shark-related (1)

sexybomber (740588) | about 7 years ago | (#20589385)

Yeah, I know I was using the Rutherford atomic model, and yes, I know it's a lot more complicated than that. Blue balls orbiting red and grey balls is a bit easier to visualize than quantum-mechanical clouds.

And I also admit to being influenced by Hollywood on the topic of matter-antimatter collisions. Guess I just want to see things blow up...

Re:non-shark-related (2, Informative)

Anonymous Coward | about 7 years ago | (#20590035)

I am a physicist but not a particle physicist. Electrons and positrons are attracted to each other because one is negatively charged and one is positively charged. When they come together they can form a stable state which is a lot like a hydrogen atom, instead of a proton and an electron you have a positron and electron. The stable state is called "positronium". "Stable" is a relative term here, positronium lasts maybe 100 nanoseconds, which is a "long" time in some sense. After that the electron and positron do annihilate one another. When they do, they produce gamma rays of about 1 MeV. I'm not sure how you would make this into a gamma ray "laser", but you could at least produce gamma rays this way.

Why is this an "atom?" (3, Insightful)

FiveLights (1012605) | about 7 years ago | (#20586595)

"These short-lived, hydrogen-like atoms consist of an electron and a positron, a positively charged antiparticle." I would think that an anti-proton and a positron (anti-electron) would be a "hydrogen-like atom." Why is the mating of an electron and an anti-electron considered an "atom?" And what force is keeping them from just annihilating each other? Why do they hook up and hang out, even for a brief time? I read about this on fark and got confused but came here to ask. So please, smart people of Slashdot, explain this to me.

Re:Why is this an "atom?" (5, Informative)

Remus Shepherd (32833) | about 7 years ago | (#20586897)

Calling an electron-positron pair an 'atom' is a bit suspect, but not too bad. Any semi-stable collection of elementary particles can be referred to as an 'atom'. They took the analogy even further, saying that when these 'atoms' met each other they formed 'molecules' -- large, electromagnetically bound accumulations of electron-positron pairs. Kinda cool.

As for what's keeping them from annihilating each other...well, at first it's angular momentum and the Pauli exclusion principle [wikipedia.org] . Both the electron and the positron are fermions, and they must occupy discrete states. Give the pair enough energy and they will occupy a semi-stable state that does not allow them to contact and destroy each other.

But before long they *do* annihilate each other. That's why it's called an 'annihilation laser'. The matter-antimatter pair collapses, liberating enormous amounts of energy in the form of gamma rays.

I think 'matter-antimatter annihilation laser' sounds cooler, but there's a certain mad scientist flavor to the 'gamma ray' bit, too.

Re:Why is this an "atom?" (1)

Tyler Durden (136036) | about 7 years ago | (#20588085)

But the Pauli exclusion principle prevents two *identical* fermions from occupying the same quantum state simultaneously. Are an electron and positron considered identical fermions or is this between two electrons and positrons within the "molecule"?

I'm also wondering just how stable the molecules are. Could they be used for a matter-antimatter propelled rocket?

Today's Thursday. Must be my armchair physicist day.

Re:Why is this an "atom?" (1)

Remus Shepherd (32833) | about 7 years ago | (#20589011)

Pauli exclusion, if I recall correctly, is also the principle that forces electrons into discrete energy states. An electron can go from state A to state B, but cannot exist in any state in between. That's what keeps the electron-positron system somewhat stable -- they have enough energy to occupy a mutually orbiting state. They have to lose all their energy at once -- not just some of it -- to exit that state and annihilate with each other. The higher the energy shift necessary, the longer it takes for a decay to occur. Thus it takes some small amount of time before their energy state decays and they annihilate. And the 'small amount of time' is mentioned in the article -- a quarter of a nanosecond.

Can this be used to make stable positronium molecules? I'd say it's pretty unlikely, as it would require even higher energies and thus make containment even more difficult. These are not truly stable systems.

But the article mentions something about using a silica 'sponge' to trap the positrons. No idea how that's supposed to work, but if it could be improved we could someday have a battery capable of producing antiparticles on demand.

Re:Why is this an "atom?" (1)

dstiggy (1145347) | about 7 years ago | (#20588183)

From my understanding then as long as the electron remains in an excited state then the exotic atom would stay stable and not annihilate itself. Would it then be possible to keep the electron in an excited state and create a stable atom and then molecules? Along this line then it would seem to me if you created a large enough amount of atoms you could create a gamma ray emitting material where gamma rays emitted as atoms annihilated each other would excited the electrons of the other remaining atoms to remain in a higher state. Eventually all of this matter would still annihilate itself but it seems to me to be a way of creating it for a long enough time for study. Also if you could find another way of keeping the electrons in a higher state you could use it as some type of anitmatter fuel.

Re:Why is this an "atom?" (1)

InfoVore (98438) | about 7 years ago | (#20589229)

I think 'matter-antimatter annihilation laser' sounds cooler, but there's a certain mad scientist flavor to the 'gamma ray' bit, too.

How about a compromise then: MAAG-LASER - Matter-Antimatter Annihilation Gamma-ray Laser

Of course the "L" should be replaced with a "G" since the Gamma-rays are the EM waves being amplified: GASER - Gamma-ray Amplified Stimulated Emission of Radiation. But we may want to stick with MAAG-LASER since MAA-GASER sounds like a southerner commenting on the result of eating too many black-eyed peas.

-I.V.

Re:Why is this an "atom?" (1)

Warbothong (905464) | about 7 years ago | (#20588985)

Of course it's an atom. It's on the periodic table between Neutronium and Suprise.

Atoms? (2, Interesting)

Tyler Durden (136036) | about 7 years ago | (#20586641)

So positronium is an atom composed of an electron and a positron. Is this then an atom without a nucleus?

Weird.

Re:Atoms? (1)

iknowcss (937215) | about 7 years ago | (#20587947)

Is positronium it's own anti-atom? If the positron were the nucleus, then it would be one thing, and if the electron were the nucleus it'd be the anti-thing. That must be where the gamma raze from :P

Re:Atoms? (1)

aaron alderman (1136207) | about 7 years ago | (#20589187)

By your reasoning Hydrogen would be an atom without a nucleus as its simply the same system but with a positive charge which is 1000x more massive.

Can they take it to three? (5, Funny)

Anonymous Coward | about 7 years ago | (#20586673)

Although dipositronium (Ps2) is considered to be a huge advance, scientists will be disappointed to discover that tripositronium (Ps3) will never be as popular as tungsten-diiodide (WII).

But (0)

Anonymous Coward | about 7 years ago | (#20586697)

Where's the kaboom? There was supposed to be an earth-shattering kaboom.

But we won't have warp drive (1)

kiick (102190) | about 7 years ago | (#20586725)

Until they can make di-lithium crystals.

i just wanna know (1)

chelanfarsight (835467) | about 7 years ago | (#20588181)

when i get my positronic brain.

Di-positronium? (0)

Anonymous Coward | about 7 years ago | (#20586821)

What kind of a name is di-positronium? Shouldn't it be called anti-helium?

Re:Di-positronium? (1)

jafuser (112236) | about 7 years ago | (#20587831)

From what I understand, both particles are leptons; there are no baryons, so it's not a normal element e.g., Helium.

Yeah but.. (1)

St.Anne (651391) | about 7 years ago | (#20586875)

That's only dangerous if you're in the ocean, what about if you're on land huh? What then!?

Re:Yeah but.. (2, Funny)

GameMaster (148118) | about 7 years ago | (#20587491)

Land shark, I mean, Pizza...

Re:Yeah but.. (1)

salec (791463) | about 7 years ago | (#20588495)

You mean, Candygram...

I think he just invented the Positron Toilet (0)

Anonymous Coward | about 7 years ago | (#20586913)

"It's like having a trickle of water filling up a bath and then you empty it out and you get a big flush," said Dr Cassidy.

Now Data can use the bathroom. ...you do not want to go in there...it is like a giant gamma ray burst...

More dangerous sharks please (1)

eebra82 (907996) | about 7 years ago | (#20587819)

A potential use of these molecules is to make extremely powerful gamma-ray lasers, possibly on sharks.
Finally! Now that the harmless sharks finally get some gamma-ray lasers on the tip of their nose, this will help them regain their position at the top of the food chain, ever since the nasty penguins started taking over their territory.

Gamma ray lasers... (1)

Khyber (864651) | about 7 years ago | (#20588647)

Forgive my ignorance but isn't a gamma ray pretty hard to shield against and focus, or was that some other form of radiation? It would seem to me making a focused beam of radiation would require very toxic materials for reflecting, and some radiation waves penetrate most anything.

Holy GRAIL (1)

jiawen (693693) | about 7 years ago | (#20588913)

Just in case no one has yet, I propose the acronym GRAIL: Gamma Ray AnnihIlation Laser. Sounds like they've been seeking it for a while, too...
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