Black holes make antimatter
I was under the impression that this happened when one of a pair of virtual particles was sucked into the black hole, and the other escaped. 50% of the time the particle that escapes will be an antiparticle.
Topflight astrophysics boffins believe they may have cracked the tricky problem of how to make antimatter, which would be useful for many purposes: for instance powering relatively practical starships, or - of course - blowing up an entire planet in one go. However, it appears that making antimatter requires the possession of a …
uses anti-electrons (positrons) to look inside the human body.
Antimatter was theorised by Dirac a long time ago.
It has been known how to create anti-matter since the early '90's with the first
first antimatter created at CERN in 1995. They created anti-Hydrogen. Admittedly this was of a very high energy and subsequently very difficult to study.
The first low energy anti-Hydrogen was created in 2002 by the ATHENA project at CERN.
Forgetting, for the moment, the difficulties of storing anti-matter if you get your hands on it (while positrons and anti-protons are capable of being stored in magnetic fields, if you combine one of each to form an atom of anti-hydrogen, suddenly it's magnetically neutral and can't be restrained so easily), are they saying that a BLACK HOLE, with gravity so MASSIVE that it can pull in EVERYTHING, including LIGHT, is actually *releasing* anti-matter?
Is that saying that anti-matter is not affected by gravity, or, even cooler, it's affected in the opposite way to normal matter?
But knowing how to produce it is half the problem, surely the annihilation would destroy where the ever it was happening resulting in a big hole of nothing? What would happen then? Would it act as a blackhole might? Would everything else close up around it, like cutting a hole in paper and then buching the rest of the paper around the hole?
Would you even want to test it?
"DOCTOR!!! My brain hurts..."
Is it just me or does it seem like the whole "dark matter" biz was dreamed up because no "reputable scientist" wanted to admit they hadn't a clue?
And as for black holes, I thought that NOTHING, not even LIGHT, could escape a black hole. Did science change when I wasn't looking? It is commonly accepted that there is a "supermassive" black hole (roughly several million times Solar mass) at the center of our galaxy and that the ludicrous gravitational pull from same is largely what holds the galaxy together as a spinning mass.
Further out on the tangent: how many gazillions of years before the black holes gobble up all matter in the universe? And is that where my keys went?
If you have a fiction called Perseus, it needs a horse to ride. Hence, you invent a fiction called Pegasus. But what's a hero without a maiden. So, you invent another fiction called Andromeda. Hero and maiden, how to get them together? To fix that problem you have a "thought experiment" - what if maiden needs to be rescued (from terrorists is good)? Great idea, really "works". And so, another fiction called Medusa. E cosi' via.
The more you invent, the better it all looks. The more fictions you have, the easier it is to juggle them together. The easier it is to "modify the behaviour" of your fictions on an ad hoc basis if your audience starts picking holes in your story. The more time you invest in all this, the more reluctant you are to give up your fictions. Especially if someone keeps throwing a lot of money your way to keep inventing them.
Things used to be so different when scientists paid for their own researches. For one, there was no incentive to cheat yourself out of the truth.
Black holes have long been thought to be a source of antimatter in the form of Hawking Radiation. The theory goes that empty space is fizzing with pairs of virtual particles that ordinarily pop into existence and subsequently vanish again after a fleeting instant. If such a pair span a black hole's event horizon, however, one of the virtual particles will be gobbled up by the immense gravity. The other is at liberty to be whisked away by a magnetic field, and there's a pretty good chance that it will be an anti-particle.
If you really want to give a physicist a headache, ask him why our universe is overwhelmingly dominated by matter rather than by anti-matter. On a related note, a spinning cobalt nucleus will spontaneously spit out an electron (beta decay), but it's always in the same direction with respect to the spin. Spooky. God definitely favours one hand over the other in our universe, but how does he know which one is which? After all, there's no external reference. Definitely spooky.
Perhaps I'm just being stupid... but, why is this a mystery?
It's been long thought that anti-matter would show anti-gravity - isn't the fact that it seems to escape such huge fields actually proof of that?
It could also be the reason WHY we see it in such large quantities - if matter/anti-matter is oalescing from the energy within (theory goes that when energy coalesces it forms equal quantities of matter and anti-matter) the only thing that will escape to be 'seen' is that able to escape the gravitational field.... i.e. something with anti-gravity, anti-matter...
Perhaps this is an oversimplification of the conundrum, but is it not possible that antimatter escapes high gravity environments because it has inverse properties to normal matter that would be drawn to black holes? Simply put, if gravity attracts normal matter would not antigravity be required to attract antimatter?
As I understand it, antimatter still has positive mass, so it is affected by gravity in exactly the same way as normal matter.
Nothing can escape from a black hole from within the event horizon - the boundary where the escape velocity required equals the speed of light. However, virtual particle pairs leading to Hawking radiation form at this boundary, so there would be no theoretical problem with one of the pair (which will be half antiparticles) being catapulted out of the region by electromagnetic effects (similar to the way particles are handled in particle accelerators).
Do the EM fields around black holes preferentially fire out positively charged particles? If so, it would explain the massive amount of positrons out there.
"when you get back your spouse, kids and mates will be long dead. Not my idea of a happy life."
Take the kids and mates with you. Leave the wife behind to handle your financial affairs. One way or another, it's a happy return.
The leather one with the anti-tweed elbow patches, thanks.
Please, can we call time on the amateur physicists so confidently sharing their complete misapprehensions?
@Jamie and others: No, it hasn't "been long thought that anti-matter would show anti-gravity". Anti-matter particles have reversed spin, charge, and other properties compared to their matter partner particle, but they have positive mass and respond to gravity in exactly the same.
As to how they escape Black Holes: the Black Hole is only inescapable to a classical approximation, i.e. Einsteinian gravity. When you take into account quantum effects, particles can escape from very close to the horizon. Particle/anti-particle pairs spontaneously appear then mutually annihilate in empty space all the time (go look up the Heisenberg uncertainty principle for why). If they happen to appear very close to the horizon of the Black Hole, one can fall in while the partner shoots off into space before they can annihilate again, creating the appearance that the Black Hole is emitting particles (both anti-matter and matter).
*sigh* I guess this is what happens when people learn their physics from Star Trek...
You make IT sound all so easy, which it would be whenever you can resolve the model of the infinitely large with the infinitely small for ITs Mutual Equilibrium. Money cannot buy it of course, but throwing money at IT allows you to bask in Reflected Glory .
Although don't be fooled into believing that "one should not increase, beyond what is necessary, the number of entities required to explain anything" .... http://pespmc1.vub.ac.be/OCCAMRAZ.html .... because one needs to be able explain everything surely.
Do that and you have a priceless Gift which Generates AI Life of ITs Own ...just as you inferred/shared. ...... although you do sound somewhat bitter as if you have compromised yourself for filthy lucre rather than compromising filthy lucre for yourself.
A black hole has a region (the famous event horizon) below which nothing can escape, but AT the event horizon the virtual particles of space, which consist of pairs of particles - one normal and one anti-mater - instead of recombining and neutalising each other can have one member swept into the black hole while the other, being just outside, can escape. This happens all the time and the idea that it does happen is actually what bought Stephen Hawkings his place at the top table. In fact, it is called "Hawking Radiation".
If there is some reason why the anti-particle is the one that escapes more often then that would make a black hole a net emitter of anti-matter.
BTW, the black hole pays the price for all of this and if starved of new material, will eventually evaporate as a result.
Well, that's what they tell me anyway.
Oh, and anti-matter has mass just like normal matter so it experiences gravity, not anti-gravity.
"We expected something unexpected, but we did not expect this" This is redundant: "did not expect this" implies, actually demands, that "this" is unexpected. But the statement opened with "we expected something unexpected". So the statement reduces to "We expected something unexpected, but this is unexpected"! So I guess they got what they expected?
Antimatter gets away from the neutron star or a black hole by means of anti-gravity. It is like melted butter and flat teflon pan theory, even if you wanted to keep the butter on the pan it would repel the teflon and leak out (known as escape velocity in physics), totally unexpected yet gastronomically beautiful.
Read your current (astro)physics. Steven Hawkins at el have shown that black holes radiate energy (and thus information) back into the universe and thus "evaporate" over an amount of time proportional to the size of the hole.
@"Nobody knows exactly how black holes and neutron stars make antimatter"
Tesseract. If you take a human in "hyperspace" and turn him 180deg to our "reality" before inserting him, he theoretically could come back with his heart on the right, etc...
Since it is possited that Black Holes (and to a certain extent neutron stars) warp the fabric of space-time (no ST references, thank you), it should not be a hard stretch to come to the conclusion that AM is simply matter which has been subjected to a "twist" when it came into close contact with the vent horizon of the object in question.
I'll collect my Nobel prize when I go get my coat.
Blacks holes suck in everything that crosses their event horizon (yes, even light) but, and this is really cool stuff worked out by "Mr Brainbox", Stephen Hawking, they expel energy.
The energy is known as Hawking radiation. Black holes are always expelling this stuff (they're not entirely sure what it is yet) and may actually evaporate.
It could be that the two are related - the radiation being emitted by the black hole is causing, or may actually, positrons.
is just bent space, that's why a massless particle like a photon is affected by gravity.
Mass bends space, and anti-matter has a positive mass.
A black hole bends space to such an extent that any passing particle massless or otherwise, matter or anti-matter, virtual or real is bent along a path into the black hole.
It hurts my head too but I find all this stuff fascinating.
What I would like to know is why the Universe came out of the big bang with such a large entropy and what happens to that entropy should the universe collapse back into a singularity. We will have to wait for a sucessful theory of quantum gravity to answer that.
Oh and what in the Universe makes light move, instead of putting it's feet up with a nice cuppa and watching an episode of Star Trek.
The 'temperature' (i.e. rate of release of hawking radiation) is inversely proportional to the mass of the black hole. The black holes in question will be ancient, and very massive due to aggregation, and just generally having lots of mass to eat in the middle of the galaxy.
further there is no reason why holes would favour emitting anti matter over matter - indeed what is emitted should be pretty much governed by probabilities. There is nothing to stop the black hole emitting a double decker bus, and provided the universe lives long enough (it won't - or at least probably won't) then it even becomes likely.
So this very large emission of one class of matter over another may give the practical cosmologists something to get excited about, but the theoreticians are all going to be having some long nights (and get quite excited too of course).
Given the relatively high concentration of matter in that space it may be that warped space time affects the probability in favour of anti matter. Which is weird since the period when spacetime was most warped (1st second or so of the universe) seems to have massively favoured matter. All very interesting, if rather puzzling.
Oh, and Luther (and amanfrommars) - Occams razor is definitely being used here. Our current best theories are generally fairly internally consistent, and do not multiply entities unnecessarily. Luther - by all means have a go at a simpler one to explain the evidence. It has to be useful, and have some predictive power to count though (no 'because the flying spaghetti monster says so' types of thing)
"are they saying that a BLACK HOLE, with gravity so MASSIVE that it can pull in EVERYTHING, including LIGHT, is actually *releasing* anti-matter?"
Maybe it is somehow radiated, like Hawkins radiation...
1. A black hole has strong gravity.
2. The 'empty' void is full of teaming pairs of particles that pop into existence randomly, and bump into each other and anihilate each other almost instantly.
Therefore, as Hawkins proposed, at the edge of a black hole, when a pair pops into existence, occasionally one half of the pair gets dragged in by the black holes gravity, and the other doesn't. Leaving one extra particle in the universe. Therefore black holes appear to emit radiation.
Well thats the jist of it. So maybe something like this could be going on. Or maybe not. But what's said in the article doesn't necessarily mean that anti-matter isnt affected by gravity.
isnt it fact all things always have two parts, man,woman,light/dark,gravity,antigravitiy.
if black holes frow out more anti-gravity parts than gravity parts then do white holes do the opposit pull in anti-gravity particals and expel gravity particals as you might expect if equal and oposit in all things is scientificly true?.
"Oh, and anti-matter has mass just like normal matter so it experiences gravity, not anti-gravity."
again i wonder , if its not anti-gravity then what is anti-gravity, the above being true, it most exist as most anti-mass surely?.
something else that bugs me, if the guy that went up to near space in the 60s(a few K above him)in that baloon and jumped out, without lots of friction making him burn up , why cant a space ship come in from slightly above his highest point (that few K)and that does have lots of friction and burns VERY hot.
why cant they come in/through at near zero speed and so not generate much friction as the .sky diver did just below them years before.
it just bugs me as i cant get any real satisfying answer.
Not that this article has much to do with Dark Matter, but here goes:
Dark Matter *has* been verified several times in the last few years. Initially, it was just a "guess" to plug a newly-discovered hole in current theories. But knowing that it might be out there, astronomers started looking for clues to its existence. Eventually, by design and by serendipity, they found it.
Google it for yourself, I'm too damned lazy. But you can start with www.badastronomy.com, they had something on these discoveries a few months back.
Dark Energy is currently in the same status as Dark Matter was initially. It plugs a hole in the theory. It might turn out like DM did, and reveal clues to its existence. Or it might not exist at all, and some other theory will be needed to "plug the gap".
As others have implied: "It's better to say nothing and be thought a fool, than to open your mouth and remove all doubt." i.e. keep your arrogant ignorance to yourself.
"...how does he know which one is which?" is like asking "Thermos bottles keep hot things hot, and cold things cold. How does the thermos know?" Both are ill formed questions.
Absolutely not. Your question is a trivial concern over thermodynamics. My point is that we live in a chiral universe and nobody knows why left or right dominates at the weak nuclear force level, in a similar way that matter dominates over antimatter. Further, to say that something is left or right *always* requires some frame of reference (transmit a TV show to an alien civilisation for example and the only way they will show it the right way round is if the movie shows a known star field or something that violates charge-parity or the like). Since the universe only has itself as a frame of reference, the only thing you can say about "left" is that it is not "right".
More about CP Violation and problems of symmetry at http://en.wikipedia.org/wiki/Cp_Violation
by stuffing a proton beam, OK quite a dense twenty-six gigaelectronvolt proton beam, onto a (cooled) 3mm diameter by 150mm long copper wire that had about *200*kilo*amps* flowing through it. Said wire dumped all sorts of junk out of the backend, some of which were Antimatter. A bit of filtering, magnetic meandering, concrete, boron and we had a beam of antiprotons. The team did this from 1981 onwards and got the Nobel Prize for physics in 1984 - but mostly for the clever faster than light beam antiproton beam densifier technology (Stochastic Cooling) which allowed the Antiproton Accumulator machine to feed the Super Proton Synchrotron and evince the W & Z intermediate vector bosons.
It was the Low Energy Antiproton Ring that first planned to decelerate an 3.5GeV/c pbar and see if, at rest , it floated UP or DOWN when acted upon by gravity. Hi Tim!
Since light has zero mass, it can move at the speed of light. Anything moving at that speed experiences infinite time dilation. Since movement requires time, light cannot be moving, so therefore exists at the point of origin and point is destruction simultaneously, even if these points are 15 billion lights years apart. Therefore, photons are not fast, just very long.
The question is more "Is there more anti-matter than matter forming?"
Virtual electron-positron pairs are constantly forming from the quantum vacuum. There should be an equal chance of the electron or the positron being the one captured.
Unless there is something to favour the electron being the one captured...
Very small mass difference (theyre always described as being the same)
Negative Charge being attracted to the Black Hole
Preference for electron spin direction
or something to favour the positron being repelled/ejected away from the hole
I can't imagine the particle density in the vacinity of a black hole is as low as "empty space" so you'd expect all the positrons to have a chance to annihilate
Maybe spinning black holes eject electrons one way and positrons the other?
"We expected something unexpected, but we did not expect this" is a contradiction in terms. If they did not expect what they got (2nd clause), it was unexpected and therefore expected (1st clause). But I was expecting a Spanish Inquisition pun... And an SI icon would be fitting...
OT re reentry from space: The parachutist was not in orbit. For the Space Shuttle to be in orbit around the Earth, it must be accelerated to something like 25000 km/hour (or miles/hour??). When it comes back down, it's hitting the atmosphere at something like this speed, which results in a lot of friction and heat. They can't come straight in, they have to skim the surface and bounce back a few times to get the speed down to where they can handle the friction... I saw a NASA guy heat up a tile with a blowtorch, then touch it with his hand - it wasn't even warm (I touched it too).
As black holes (probably) have very strong magnetic fields and may be rapidly spinning, that would be enough to send positrons and electrons escaping at the event horizon in opposite directions. If the density of matter nearby is low enough, a significant proportion might make it far enough away to form clouds of particles?
@everything comes in twos:
Someone's been watching too much Red Dwarf again, haven't they?
"if black holes frow out more anti-gravity parts than gravity parts then do white holes do the opposit pull in anti-gravity particals and expel gravity particals as you might expect if equal and oposit in all things is scientificly true?."
@ Mike Bell
"Further, to say that something is left or right *always* requires some frame of reference (transmit a TV show to an alien civilisation for example and the only way they will show it the right way round is if the movie shows a known star field or something that violates charge-parity or the like)."
Of course, making the assumption that the biology of the alien civilisations' viewing apparatus (eyes) is made up the same way as us, and can see the same wavelengths of light as us? With the level of biodiversity that we see within our own humble sphere, (and I'm thinking along the lines here that canines/felines see different wavelengths of light to humans, they can see movement of light on a TV screen, but not the definitive shapes (I'm sure I read that somewhere...)) who's to say that the aliens can even see what's being transmitted? Not that I'm booboo-ing your comment, just that sometimes assumptions can thow an idea so far off course.
Right, got that out of the way.
Where is the Paris Hilton angle?
Antimatter has opposite CHARGE to matter not negative MASS, so no antigravity for you trek fans.
The charges on atomic/subatomic particles are not the same as magnetism, which for atomic particles is based on spin (and for molecules also based on dipole moment) so anti-hydrogen is no more magnetically neutral than an antiproton, moreover a magnetically neutral element could not be held in a magnetic field. Sorry to piss on your chips, chaps.
I also imagine that the discovery of interstellar antimatter will not lead to laser swords, time travel, hovering skateboards, teleportation, warp drives or the possbility of finally meeting and having sex with humanoids sporting an amazing variety of different shaped latex foreheads and eyebrows.
One of the Stephen Hawking books I read, explained the phenomenom of Hawking Radiation. If you apply a quantum approach to the analysis of gravitational effects close to a black hole's event horizon, Heisenberg's uncertainty principle states that nor the position nor the speed of a particle can be precisely determined. In the conditions of extreme gravitational warps close to a singularity (an area where the laws of physics are rather unpredictable), a particle MAY exceed the speed of light limit for a very short amount of time (just enough to allow it to escape). That breaking the light barrier implies that the particles travel BACK in time, is an expected outcome since all paths that approach a singularity end at singularity itself. Remember extreme gravity does funny things to the laws of physics. This could be complete bollocks of course, Hawking himself admitted that he wasn't sure this was the correct explanation and that a quantum theory of gravity has not been developed yet.
Anti-matter behaves EXACTLY like matter, follows gravitational warps (its attracted by gravity), is affected by electromagnetic fields, and is affected by the strong and weak nuclear forces to both radiate and form atoms. Negative energy, however, behaves in an opposite fashion than natural energy. Negative energy can be created by hermetically closing off a region between two perfectly flat plates, extracting ALL particles and cooling the whole system to absolute zero. Because the region between the two plates is hermetically sealed from the outside universe and it is at absolute zero, the net energy between the plates is zero. However because of the Heisenberg uncertainty principle, the virtual particles that are created both between the plates and outside of them, create an energy deficit inside the plates. The virtual particle pressure outside the plates is greater that inside the plates which causes the system to have a negative energy state. Negative energy anti-gravitates but if you expose the fictional box, to the Earth's gravitational field, it will still fall down (the earth's field is still greater than the anti-gravity field). The above effect is called the Cassimir effect, and was theorized by Dutch physicist Hendrik Casimir and was used by Kip Thorne in the scientific basis for the movie, Contact. The effect has been experimentally tested and the Casimir force was detected.
British boffin, Paul Davies wrote about this in his book "How to Build a Time Machine".
Is it possible that the combination of matter and anti-matter does not result in total destruction but actually produces Dark Matter. That might explain why there is so much of it floating around undetected. It might also explain why we in the 'matter reality' see so little of the 'anti-matter reality'.
In a universal Big Bang event it seems conceivable that a huge proportion of the 'proto-matter' was split up into what we regard as matter and its opposite, anti-matter. When the two aspects meet they fuse back together to form the original proto-matter or what we regard as Dark matter.
Or is that too obvious?
"The charges on atomic/subatomic particles are not the same as magnetism... a magnetically neutral element could not be held in a magnetic field"
- until the charged particle starts moving relative to the magnetic field, which it must in this case due to gravity if nothing else. This being the principle behind the generation of aurora on Earth and the electric motor.
This used to be taught at GCSE as the left hand rule, but obviously physics education isn't what it used to be.
Of course the magnetic field around a black hole may not do anything other than concentrate the particles at the 'poles', as with the Earth's field. But initially at least positively and negatively charged particles would experience forces in opposite directions.
Dark matter is this generation of astronomers' Vulcan and, like Vulcan, it explains the observed results very nicely and can't be detected. And like Vulcan, it can't be detected because ain't there. In a third parallel with Vulcan, I'd bet the real reason comes from relativity or some other modification to gravitational theory.
The properties of anti-matter are reversed, but NOT mass.
Eg: Electron: Spin: 1/2 Electric charge: -e Mass: Me
Positron: Spin:-1/2 Electric charge: +e Mass: Me
Properties such as Strangeness, Charm, Spin, Charge, Topness, Bottomness, are reversed but mass is always conserved.
This is why a Messon (Such as a Si Messon) A combination of a Charm - Anti-Charm quarks has a mass of 3.1GeV/C^2 (and not Zero).
Looking at Gravity from general relativity it is a curvature in spacetime by matter or energy which means particles follow Geodesics (trajectories) which are the shortest routes (Like straight lines in flat space) this means they're falling in space not transfering force like electromagnetic interactions (photons) between them.
And If you look at it Quantum Mechanically then the whole process involves gravitons, lets wait for them to confirm the existance of these before we start conjuring up anti-gravitons which would mean Messons don't exist.
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