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CERN Antimatter Experiment Produces First Beam of Antihydrogen

Soulskill posted about 8 months ago | from the now-we-just-need-some-dilithium-crystals dept.

Science 136

An anonymous reader writes "Matter and antimatter annihilate immediately when they meet, so aside from creating antihydrogen, one of the key challenges for physicists is to keep antiatoms away from ordinary matter. To do so, experiments take advantage of antihydrogen's magnetic properties (which are similar to hydrogen's) and use very strong non-uniform magnetic fields to trap antiatoms long enough to study them. However, the strong magnetic field gradients degrade the spectroscopic properties of the (anti)atoms. To allow for clean high-resolution spectroscopy, the ASACUSA collaboration developed an innovative set-up to transfer antihydrogen atoms to a region where they can be studied in flight, far from the strong magnetic field (scientific paper)."

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Slashdot produces fist beam of nigger jizz (-1, Flamebait)

niggers sucking cock (3506657) | about 8 months ago | (#46028753)

You are alll fucking bastards that need to be raped by horses

Re:Slashdot produces fist beam of nigger jizz (-1)

Anonymous Coward | about 8 months ago | (#46028811)

Do you work for Boeing?

Re:Slashdot produces fist beam of nigger jizz (-1)

Anonymous Coward | about 8 months ago | (#46028847)

I stuck my anti-hydrogen beam up your mom's ass while your cuck dad jerked on his 2-inch dinghy.

-- Ethanol-fueled

Re:Slashdot produces fist beam of nigger jizz (-1)

Anonymous Coward | about 8 months ago | (#46029181)

What's your problem, guy?

Re: [Ignorance] (1, Flamebait)

Jmac217 (3006299) | about 8 months ago | (#46029573)

You may like cowering behind your monitor, sitting in your own filth of chip crumbs, and typing with your sticky fingers; but you're the argument against anonymity on the internet.

Re: [Ignorance] (0)

Anonymous Coward | about 8 months ago | (#46029605)

Says the guy who uses a handle called "Jmac217".

Re: [Ignorance] (1)

CheezburgerBrown . (3417019) | about 8 months ago | (#46029829)

Problem?

Re: [Ignorance] (0)

Anonymous Coward | about 8 months ago | (#46029877)

Only that the person pleading for an end to anonymity on the internet himself chooses to do his online activities in a way that is anonymous. I thought that would have been obvious.

Re: [Ignorance] (1)

Desler (1608317) | about 8 months ago | (#46030327)

Yeah, he rails against Internet anonymity and uses a pseudonym to post. He should make his post under his real name otherwise he's being a hypocrite.

Re: [Ignorance] (1)

Wycliffe (116160) | about 9 months ago | (#46032803)

You can be against anonymous and in favor of pseudoanonymous without being a hypocrite.
There is a huge difference between anonymous and pseudoanonymous.
Pseudoanonymous allows users to be blocked, get a reputation either good or bad, and actually
have a presence. It's been shown that people are even more true to their real self
when using a pseudonym. That's completely different than the anonymous people that
post stuff just to get a respond and would immediately be banned and/or ignored if they had
a real account.

Re: [Ignorance] (1)

gmhowell (26755) | about 9 months ago | (#46032939)

Yeah, he rails against Internet anonymity and uses a pseudonym to post. He should make his post under his real name otherwise he's being a hypocrite.

Shouldn't you be chasing down a refurbed WWII battleship?

Re: [Ignorance] (1)

Duhavid (677874) | about 8 months ago | (#46030031)

Erasing moderation

Re: [Ignorance] (0)

Anonymous Coward | about 8 months ago | (#46030285)

Typed up by the tough guy behind his own monitor. Oh the irony...

Will this open Stein;s Gate? (1, Flamebait)

danbuter (2019760) | about 8 months ago | (#46028755)

I hope not. A future controlled by CERN is terrifying.

Re:Will this open Stein;s Gate? (2)

K. S. Kyosuke (729550) | about 8 months ago | (#46028865)

Don't worry, she can't take much more of this anyway.

Re:Will this open Stein;s Gate? (0)

Anonymous Coward | about 8 months ago | (#46028887)

It's happening. El Psy Kongroo

Re:Will this open Stein;s Gate? (1)

metlin (258108) | about 8 months ago | (#46029065)

Steins;Gate bro.

Re:Will this open Stein;s Gate? (0)

Anonymous Coward | about 8 months ago | (#46029201)

No, but I hear they used to play a lot of Baldur's Gate at CERN, though.

Re:Will this open Stein;s Gate? (0)

Anonymous Coward | about 9 months ago | (#46031581)

Odd that this was modded "Flamebait" (it's a reference to Steins;Gate, a game made into an animated series recently)

And it's probably because he got the name wrong: it's SERN, not CERN

First! (1)

nomorecwrd (1193329) | about 8 months ago | (#46028761)

Anti-hydrogen weapon?

Re:First! (4, Insightful)

fuzzyfuzzyfungus (1223518) | about 8 months ago | (#46029159)

'Weapons that don't work if there is matter between you and the target' are probably kind of a niche at present...

Re:First! (5, Funny)

martyb (196687) | about 8 months ago | (#46029287)

Anti-hydrogen weapon?

'Weapons that don't work if there is matter between you and the target' are probably kind of a niche at present...

So, basically, if an enemy got hold of this, it wouldn't matter? ;)

Re:First! (2)

CODiNE (27417) | about 8 months ago | (#46029763)

Just shoot it behind a powerful laser blast.

Re:First! (2)

cheesybagel (670288) | about 8 months ago | (#46029963)

Precisely. Something in front to cleanup the matter along the way, then the anti-hydrogen. But its probably easier to fire positrons.

Re:First! (4, Insightful)

OneAhead (1495535) | about 8 months ago | (#46030421)

Parent and GP's suggestions might work in SF, but in real physics, a powerful laser blast will just break the ordinary matter into smaller pieces, which will still be sitting in the way. As for the positrons, they won't quite annihilate the ordinary matter; some of them would annihilate with electrons, but most of them would convert neutrons into protons, if I remember the nuclear chemistry chapters of my bachelor's courses correctly. The resulting unstable cores would either decay or fission, but the products would still be ordinary matter, and no matter (pun not intended) how long you keep repeating this, there would still be a lot of ordinary matter left that cannot be converted to energy any further by bombarding with positrons. </humorless pedantic nitpic>

Re:First! (-1)

fisted (2295862) | about 9 months ago | (#46031137)

a powerful laser blast will just break the ordinary matter into smaller pieces, which will still be sitting in the way.

Right, because particles coming loose tend to just remain floating in place, rather than being pulled down by gravity, clearing the way.

Re:First! (4, Informative)

OneAhead (1495535) | about 9 months ago | (#46031433)

Here's a serious answer, just in case you're not going along with the joking tone of the 2 posts I replied to...

I thought we were (implicitly) talking about the presence of air making terrestrial use of the weapon impossible. Particles coming loose tend to fly around at high speeds is somewhat random directions. Some of them will remain in the way of the antimatter projectile/beam, some of them will go out of the way but hit a molecule and return where they came from, some of them will create some backscatter effect (like a billiard ball being launched at high speed on a pool table full of other balls), causing molecules of air to get into the way. Even if one could fire a hypothetical ray that clearly annihilates all matter ahead of an antimatter projectile/beam, air would quickly rush into the vacuum being created (of course, having such a ray at one's disposal would mostly remove the point of using an antimatter projectile/beam). Whatever happens, there won't be the necessary hard vacuum for the antimatter projectile/beam to proceed. Even air at very low density would exert an incredibly strong braking/beam dispersal force because of the energy released when it collides with antimatter.

Also, in the present discussion, gravity is far too weak a force to be relevant at all. If you have to wait for gravity to remove stuff out of the way, air will have been given time to take that stuff's place a hundred times over. That's why there's no hard vacuum behind objects in (subsonic) free fall. Now in space, there is no air, but little gravity either...

Re:First! (0)

fisted (2295862) | about 9 months ago | (#46031195)

[...] the nuclear chemistry chapters [...]

It's spelled Nucular.

Re:First! (0)

Anonymous Coward | about 8 months ago | (#46030477)

Just shoot it behind a powerful laser blast.

Someone get the sharks!

Re:First! (1)

MarkRose (820682) | about 8 months ago | (#46029895)

One could say It matters so little it antimatters.

Re:First! (1)

nomorecwrd (1193329) | about 8 months ago | (#46029305)

mmm... yeah, more like some sort of satellite to satellite weapon maybe.
What are the chances of hitting space debris of some sort?

Hold that thought... Can we use this thing to clean the orbit or the path before, let's say the ISS?

Re:First! (1)

rlwhite (219604) | about 8 months ago | (#46029501)

The solar wind might not be all that dense [hypertextbook.com] , but I still wouldn't chance the antimatter finding a random ion too close to the launcher.

Re:First! (3, Interesting)

danlip (737336) | about 8 months ago | (#46029673)

The annihilation of a single hydrogen atom probably isn't going to hurt much, it's not that much energy.

Re:First! (1)

ClickOnThis (137803) | about 9 months ago | (#46032319)

The solar wind might not be all that dense [hypertextbook.com] , but I still wouldn't chance the antimatter finding a random ion too close to the launcher.

Depending on the altitude, there's more up there than just the solar wind. The escaped particles from the ionosphere, for one.

Much of the space environment around the earth (in fact in the whole universe) contains plasma at varying densities. Whether an antimatter beam could travel very far in earth orbit would depend on its flux and the ambient mean-free path for the antimatter particles in question. I'm not sure what the numbers would be for antimatter, but some quick Googling reveals that non-exotic matter typically has a mean-free path on the order of 1 m in low earth orbit, 1 AU in interplanetary space, and potentially thousands of light-years in interstellar space.

Re:First! (1)

TrollstonButterbeans (2914995) | about 9 months ago | (#46032403)

Jokingly, every blackhole could be composed solely of antimatter and the universe would be no different. Except, well, actually this statement is true --- every blackhole could be exclusively made of antimatter, because beyond the event horizon the contents of a blackhole cannot interact with the rest of the universe except gravitationally.

Pure Anti-Hydrogen? (2, Funny)

cold fjord (826450) | about 8 months ago | (#46028785)

That is only one ionization away from something potentially very dangerous [youtube.com] .

Re:Pure Anti-Hydrogen? (1)

Bill_the_Engineer (772575) | about 8 months ago | (#46029213)

Mmmmm... Bugles.

giant black hole building carbon pump (-1)

Anonymous Coward | about 8 months ago | (#46028911)

never a better time to consider ourselves in relation to creation & other stuff that really matters freeing the innocent stem cells & listening to the moms et pals

SW:EP4 "Stand By..." (2)

tedgyz (515156) | about 8 months ago | (#46028929)

This is eerily similar to the famous Death Star scene in Episode IV [youtube.com] . You can even imagine the control panel and sounds are not too different.

Re:SW:EP4 "Stand By..." (0)

Anonymous Coward | about 9 months ago | (#46031647)

This is eerily similar to the famous Death Star scene in Episode IV [youtube.com] . You can even imagine the control panel and sounds are not too different.

Similar in the same sense that a grain of sand and the Sun are similar in size.

I"m working on anti-oxygen (1)

bob_super (3391281) | about 8 months ago | (#46028957)

The party potential of anti-H2O is just too great.

Re:I"m working on anti-oxygen (1)

JustOK (667959) | about 8 months ago | (#46029041)

do you KNOW how dangerous anti - dihydrous monoxide IS?!?!

Re:I"m working on anti-oxygen (4, Funny)

bunratty (545641) | about 8 months ago | (#46029255)

There are no known reports of fatalities due to it, and there are no regulations against its use, so I conclude it must be perfectly safe!

Re:I"m working on anti-oxygen (0)

Anonymous Coward | about 8 months ago | (#46030655)

Of course it's safe --- if it's the opposite of extremely dangerous dihydrogen monoxide, a few milliliters in your lungs should provide immortality.

Re:I"m working on anti-oxygen (2)

narcc (412956) | about 8 months ago | (#46030945)

That's where you're wrong. It's completely unregulated and has not been evaluated by the FDA. We need to protect our children from this at all cost.

Re:I"m working on anti-oxygen (0)

Anonymous Coward | about 9 months ago | (#46032645)

You ate chili beans?

I'm waiting for anti-helium. (1)

Anonymous Coward | about 8 months ago | (#46029025)

I want anti-helium so I can inhale and talk LOWER.

Re:I'm waiting for anti-helium. (0)

Anonymous Coward | about 8 months ago | (#46029055)

I want anti-helium so you can be annihilated trying.

Re:I'm waiting for anti-helium. (5, Informative)

Anonymous Coward | about 8 months ago | (#46029073)

Sulphur Hexafluoride [youtube.com] already does this.

Re:I'm waiting for anti-helium. (4, Insightful)

DMUTPeregrine (612791) | about 8 months ago | (#46029639)

Note that it can settle in the lungs, if you inhale too much and can't exhale it you can suffocate. You won't feel it either because the CO2 will rise and exit the lungs. If you experiment with breathing it in, stand on your head after a few seconds and breathe out/in deeply.

Re:I'm waiting for anti-helium. (1)

gmhowell (26755) | about 9 months ago | (#46032949)

Note that it can settle in the lungs, if you inhale too much and can't exhale it you can suffocate. You won't feel it either because the CO2 will rise and exit the lungs. If you experiment with breathing it in, stand on your head after a few seconds and breathe out/in deeply.

Sounds like a cue for the 'feel yourself breathing' copypasta.

Re:I'm waiting for anti-helium. (0)

Anonymous Coward | about 9 months ago | (#46031173)

Or maybe just Nitrous Oxide.

Re:I'm waiting for anti-helium. (1)

i kan reed (749298) | about 8 months ago | (#46029079)

I know this is a "funny"-because-I'm-intentionally-misunderstanding-science post, but sulfur hexafloride [wikipedia.org] will totally help.

any form of combustion results in..... (1)

Anonymous Coward | about 8 months ago | (#46029075)

something less useful? what could be more less useful than firing all of our guns at once & exploding into space?

carbon monoxide.. hot air (0)

Anonymous Coward | about 8 months ago | (#46029153)

like we don't have enough of that already too? are we daft or just ordinary hostages..

Re:any form of combustion results in..... (1)

Gareth Iwan Fairclough (2831535) | about 8 months ago | (#46029407)

something less useful? what could be more less useful than firing all of our guns at once & exploding into space?

Who doesn't like heavy metal thunder?

Re:any form of combustion results in..... (1)

Meyaht (2729603) | about 8 months ago | (#46029781)

or racin with the wind...?

Typical egg-heads, over thinking (5, Funny)

mcmonkey (96054) | about 8 months ago | (#46029095)

This may be a case where the experts are too close to the problem to see the simple solution.

Put the antihydrogen in a container made of antimatter, then annihilation will not be an issue.

Perhaps some sort of rigid anti-dirigible

Re:Typical egg-heads, over thinking (0)

Anonymous Coward | about 8 months ago | (#46029219)

Oh, the anti-Huge Manatee!

Re:Typical egg-heads, over thinking (1)

pushing-robot (1037830) | about 8 months ago | (#46029269)

Good idea. I'll call anti-Hitler; he's always eager to help.

Anti-hydrogen? WTF? (0)

Anonymous Coward | about 8 months ago | (#46029115)

And what, pray tell, is wrong with hydrogen? Without it you can't have water and life itself would be impossible.

I for one, am VERY pro-hydrogen!

News for nerds... (5, Funny)

Anonymous Coward | about 8 months ago | (#46029123)

Stuff that anti-matters.

the stuff life is unmade from (0)

Anonymous Coward | about 8 months ago | (#46029191)

perfect balance requires a lot of free space

Re:News for nerds... (1)

bobbied (2522392) | about 8 months ago | (#46029387)

Stuff that anti-matters.

You mean "dash" "Slash" "dot" right? Chroot jail for you!

this is great news! (1)

Tumbleweed (3706) | about 8 months ago | (#46029429)

The first step towards the inevitable anti-Hydrogen Economy, yay!

Cool science coming... (5, Interesting)

MetricT (128876) | about 8 months ago | (#46029459)

http://arxiv.org/abs/1106.0847 [arxiv.org]

One of the most interesting physics papers I've read in recent years. Does away with dark matter by presuming that antimatter has the opposite gravitational sign as matter (which pops out very naturally once you apply CPT to general relativity).

As the electromagnetic force is almost 10^40 times stronger than gravity, it would be virtually impossible to test with anti-protons or positrons. But with electrically neutral anti-hydrogen, it becomes potentially testable.

like fertilizer plants (0)

Anonymous Coward | about 8 months ago | (#46029643)

everyone is happy (except for the smell) until it explodes...

Re:Cool science coming... (1)

Anonymous Coward | about 8 months ago | (#46029969)

Classical Physics Theories?
Committee for the Prevention of Torture?
Current Procedural Terminology?
(Urban Dictionary Warning) Colored People Time?

Re:Cool science coming... (0)

Anonymous Coward | about 8 months ago | (#46030281)

CPT symmetry [wikipedia.org] .

Re:Cool science coming... (3, Informative)

Mashdar (876825) | about 8 months ago | (#46029985)

Do you mean does away with dark energy? Because dark matter is supposed to have positive mass, so I don't see how adding negative mass would remove the need for it?

Re:Cool science coming... (0)

Anonymous Coward | about 8 months ago | (#46030365)

Antimatter does not have negative mass. I don't understand where your "negative mass" is coming from.

Re:Cool science coming... (2, Insightful)

Anonymous Coward | about 8 months ago | (#46030533)

Me neither. Things are often helped if people even just read the abstract they're talking about.

"Assuming that a particle and its antiparticle have the gravitational charge of the opposite sign, the physical vacuum may be considered as a fluid of virtual gravitational dipoles. Following this hypothesis, we present the first indications that dark matter may not exist and that the phenomena for which it was invoked might be explained by the gravitational polarization of the quantum vacuum by the known baryonic matter."

Gravitational charge of the opposite sign is not the same as negative mass, no more than an electron or a proton make antiprotons because they've got opposite charge.

Re:Cool science coming... (0)

Anonymous Coward | about 9 months ago | (#46032077)

Read the paper yourself. What they are calling "gravitational charge" is defined on the second page as being gravitational mass, and that antimatter would repel matter with a negative gravitational mass. Or you could just look at the abstract, since the whole idea of it being a gravitational dipole implies it is doing the opposite gravitationally as matter. That doesn't help with a deficit of mass in a system, and could make it worse depending on how much antimatter is around.

Re:Cool science coming... (1)

CanEHdian (1098955) | about 8 months ago | (#46030715)

I don't understand where your "negative mass" is coming from.

Another one that never watched ST:TAS... from Memory Alpha's description of Beyond the Farthest Star [memory-alpha.org] :

En route to investigate, the Enterprise suddenly experiences severe hypergravitational effects from Questar M-17's negative star mass.

Re:Cool science coming... (1)

smaddox (928261) | about 9 months ago | (#46031821)

Polarized gravitation would also make some forms of man-made time travel possible, which would be quite interesting. It would be very revolutionary if antimatter turned out to have opposite gravitational sign. Unfortunately, we're probably still several years from knowing. Still exciting, though.

Re:Cool science coming... (1)

Anonymous Coward | about 9 months ago | (#46032215)

You are mistaken. Antimatter cannot have the opposite gravitational sign as matter in general relativity. If it did, it would be possible to distinguish between an experiment performed in a gravitational field (e.g. standing on earth, antimatter released in a vacuum chamber would "float up") and an experiment performed in an accelerating rocket (e.g. antimatter released in a vacuum chamber would be "left behind" and would "fall down").

You may be familiar with the fact that light is affected by gravitation, despite the fact that photons have zero rest mass and the photon is its own antiparticle. This is reflected in the gravitational bending of starlight. You may be less familiar with the fact that photons themselves gravitate – for instance, a reflective box full of photons has a stronger gravitational field than a reflective box containing no photons. The conclusion I'd like for you to draw from this thought experiment is that positive energy gravitates positively – even in the complete absence of matter.

When an electron and an anti-electron annihilate into two gamma rays (photons), it is obvious that a positive amount of energy is released. Since energy is conserved, that means that a positive amount of energy went into the annihilation. If, as you claim, antimatter anti-gravitates, then it would have to have negative energy (since we already observed with photons that positive energy gravitates positively). Since a particle and its antiparticle have identical masses, the magnitude of their rest energies are the same (via the famous formula E^2 = m^2 c^4 + p^2 c^2, which you may have seen before in simplified form). So if antimatter anti-gravitates, then the anti-electron has equal negative energy to the positive energy of the electron, and the net energy going into the reaction is *zero*. Then the net energy coming out of the reaction is zero, and hence gamma rays are not produced. Since this is in direct contradiction with experimental observation, we can conclude that in fact anti-matter does not anti-gravitate.

AntiHydrogen ! (0)

Anonymous Coward | about 8 months ago | (#46029519)

Can I use it in my Anti-Zeppelin? How about my Anti-Hydrogen Vehicle?

Re:AntiHydrogen ! (1)

tomhath (637240) | about 9 months ago | (#46031313)

Can I use it in my Anti-Zeppelin?

That would be a Led Zeppelin (kinda like a lead balloon...you can look it up).

Re:AntiHydrogen ! (1)

gmhowell (26755) | about 9 months ago | (#46032967)

I thought a Led Zeppelin was more like a New Yardbird...

Star Trek technology coming true. (1)

Anonymous Coward | about 8 months ago | (#46029697)

"To allow for clean high-resolution spectroscopy, the ASACUSA collaboration developed an innovative set-up to transfer antihydrogen atoms to a region where they can be studied in flight, far from the strong magnetic field (scientific paper)."

Let me guess. It involves the use of Dilithium crystals.

ELIAAHM (0)

Anonymous Coward | about 8 months ago | (#46029811)

Okay, so what exactly happens when matter and anti-matter "annihilate?" Do they get changed into energy? Do they just "disappear" from the universe? Where does the mass go? Explain it like I'm an an Art History major.

Re:ELIAAHM (2)

makotech222 (1645085) | about 8 months ago | (#46029901)

100% of the mass turns into energy, so anti hydrogen + hydrogen = 2mc^2 joules, IIRC.

Re:ELIAAHM (2)

makotech222 (1645085) | about 8 months ago | (#46029913)

Oh, and IIRC, two photons are produced as the carriers of the energy, in opposite directions to conserve momentum.

Re:ELIAAHM (1)

SleazyRidr (1563649) | about 8 months ago | (#46029995)

Doesn't the anti-hydrogen have negative mass, so the combined mass of the hydrogen and anti-hydrogen would be 0? I understand that two photons are created, but I'm not quite sure where the energy comes from.

Re:ELIAAHM (1)

Anonymous Coward | about 8 months ago | (#46030211)

Antiparticles have the same mass as their particle counterparts. We haven't actually found anything with negative mass yet, and only have the hypothetical tachyon in that category.

Re:ELIAAHM (0)

Anonymous Coward | about 8 months ago | (#46030329)

Even that isn't, strictly speaking, true. A tachyon might still have positive mass, just it would propagate (for whatever reason) along spacelike geodesics. GR doesn't really allow for negative (gravitational) mass, but it does allow for tachyons.

Re:ELIAAHM (1)

SleazyRidr (1563649) | about 8 months ago | (#46030581)

Oh, I guess I need to do some more reading. I had the impression that anti-particles were basically the opposite of regular particles in every way.

Re:ELIAAHM (1)

Anonymous Coward | about 8 months ago | (#46030705)

Nope. Quantum numbers are the opposite, but that's a more subtle thing, since there are particles -- including force carriers -- which are their own anti-particle (which immediately implies, for instance, that positrons and electrons are both influenced by magnetic fields in exactly the same way, just with opposite charge). Mass isn't a quantum number, but is rather... well, basically, a form of energy, so particles and their anti-particles have the same.

(To entertain myself adding a layer of complication on top, super-symmetric partners of particles *do* have different mass and aren't anti-matter. Assuming they exist, which personally I suspect they don't.)

Re:ELIAAHM (1)

Dragonslicer (991472) | about 9 months ago | (#46031661)

Antiparticles have the same mass as their particle counterparts. We haven't actually found anything with negative mass yet, and only have the hypothetical tachyon in that category.

Tachyons don't have negative mass, they have imaginary mass (i.e. m^2 is negative).

Re:ELIAAHM (4, Informative)

joe_frisch (1366229) | about 9 months ago | (#46031465)

They turn into "energy", but it may not be very straightforward. Electrons and anti-electrons (positrons) usually annihilate to a pair of gamma rays - about as close to "pure" energy as you can get.

Anti protons and protons annihilate in a more ugly fashion since each is a bag of quarks. You can get pions that decay into neutrinos and muons which then decay into positrons and neutrinos. The muon decay is fairly slow - ~2 microseconds, enough for them to travel almost a kilometer.

In the end you get gamma rays, neutrinos (of various types), electrons and positrons. The combined energy (both their mass energy and their kinetic energy) of all the particles adds up to the original mass energy of the matter and antimatter, and any other energy put into the process.

Because protons and anti-protons are complex, it is very difficult to make anti-protons - only something like 1/100,000 collisions generates one, the rest just make pions and other junk. Then once you have the anti-protons its difficult to slow them down enough and cool them to where they will combine with the positrons. Is a very impressive and complicated experiment.

BTW- it is not a path to any reasonable energy storage, the efficiency of making anti-protons is much too low. I don't know of any even design concepts that would have usable efficiency.

Real Question (0)

Anonymous Coward | about 8 months ago | (#46029883)

If 1) anti-matter is and can not be composed of matter
and 2) electrons are matter
and 3) magnetism is the interaction between electrons
then:

How can anti-matter be magnetic?

Re:Real Question (1)

Anonymous Coward | about 8 months ago | (#46030139)

1) is true
2) is true
3) is true... but incomplete, and slightly misunderstands the nature of electromagnetism

electromagnetism is a force carried by photons between protons and electrons -- or between antiprotons and anti-electrons (which are also called positrons). since a photon is its own anti-particle, it's the same force. so we can use *electric* currents to generate magnetic fields that control positronic currents or the movement of charged antimatter.

one way to view a positron is as an electron moving backwards in time. (literally. when feynman was doing his phd with wheeler they used this extensively.) given that, it's obvious that positrons have to be influenced by electromagnetism. it's just an electron in reverse going back around the spiral.

Re:Real Question (0)

Anonymous Coward | about 9 months ago | (#46032097)

Electromagnetism is the interaction between particles with charge and electromagnetic fields. Quarks, electrons and some other particles have charge, so they can interact with magnetic fields, although some situations are more subtle than others. Even neutral atoms and neutrons can interact with electromagnetism because they have components that are charged.

Cool (0, Offtopic)

jd2112 (1535857) | about 8 months ago | (#46030043)

Can we combine antihydrogen with antioxygen and find out if antiwater is dry?

Re:Cool (0)

Anonymous Coward | about 8 months ago | (#46030173)

IT BURNS IT BURNS

Re:Cool (0)

Anonymous Coward | about 8 months ago | (#46030587)

Antiwater would act just like water in the context of other antimolecules. Antiwater would explode if it came in contact with standard matter.
 
  I do not immediately see trolls.

Re:Cool (1)

celle (906675) | about 9 months ago | (#46032375)

"Antiwater would explode if it came in contact with standard matter.

    I do not immediately see trolls."

          Then lets find some trolls and test that antiwater idea out.

Set aside your differences (0)

Anonymous Coward | about 8 months ago | (#46030511)

"Anti-matter - can't we just get along? Can't we all just get along?" - Rodney King

Don't envy me (0)

Anonymous Coward | about 9 months ago | (#46032225)

I know how to produce a beam of anti-anti-hydrogen.

To boldly start going? (1)

Pumpkin Tuna (1033058) | about 9 months ago | (#46032359)

I think this is a good sign to go ahead and start building the Enterprise. Too early?

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