Anti-matter

Geiger

Basically, I'm wondering if Antimatter has actually been created? It's been discussed in a novel I'm reading and that has got me interested. I'm not exactly gifted in the field of science so I'd appreciate any novice friendly info you have.

qz

Ah yes, Angels agus Demons. Is anti-matter real?

Geiger

Yep, that's the novel

Altheus

I want to kill Dan Brown.

Altheus

Oh... Don't forget to WIKI: http://en.wikipedia.org/wiki/Antimatter

Geiger

Geiger wrote:

Basically, I'm wondering if Antimatter has actually been created?

Yes. I believe positrons are created all the time in labs.

Good old Pair Production.

Geiger

Altheus wrote:

I want to kill Dan Brown.

Why so? I take it his science isn't up to scratch...

Son Goku

Anti-matter has been made. In very small amounts, nowhere near enough for a bomb though, which is its use in that book.
We've only made enough to light a bulb.

nesf

Scientific American had a good article this month on antimatter and the recent advances and creation of anti-atoms.

Linkage for people who don't buy it here



Oh and Dan Brown is a god. I'd rank him above Einstein and Fenyman for his contribution to the sciences.

What are u, crazy? Dan Brown is nothing but a novelist who takes one small fragment of truth or conjecture, blows it up to get a book from it, (also using many unproven statements, making them out to be accurate i might add) and then some pblind fans take every word he utters to be absolutely true even when much is proved to be false.
If you rate Brown to be a God, try reading a little book called "The Da Vinchi Hoax". But everyone is intitiled to their own opinion.

dudara

Yes, he is a novelist. His job is to entertain. Nothing more. Why do people feel the need to berate others for reading something that they enjoy.

nesf

Deleted User wrote:

What are u, crazy? Dan Brown is nothing but a novelist who takes one small fragment of truth or conjecture, blows it up to get a book from it, (also using many unproven statements, making them out to be accurate i might add) and then some pblind fans take every word he utters to be absolutely true even when much is proved to be false.
If you rate Brown to be a God, try reading a little book called "The Da Vinchi Hoax". But everyone is intitiled to their own opinion.

Ahem.

Since you seem to be unfamiliar with it, here's your new word for the day....

Sarcasm.


Although, you are new enough that I forgive you.

Capt'n Midnight

Making antimatter is a very wastefull process.

The higher water is the more energy it has, look at hydroelectric powerstations.
If you want to raise water to a higher level you could pour a bucket of water on to the ground, some of the drops splashed back may get to a higher level than the bucket. But most of the water is wasted.

Producing antimatter is far less efficient.

Storing antimatter is well nigh impossible at present, protons or electrons repel their own kind so you have to use atoms. The problems of storing the simplist atom anti hydrogen are similar to fussion, no one has made a container that can hold a plasma away from the walls of the container. (you can freeze it but still the problem of not allowing anything to touch it. )

Anti Helium - weird physical properties when you liquify it , just like real helium, so actually worse for storage than anti-hydrogen.

next up is Anti-Lithium, its a metal, solid at room temperature so you can use electromagnetic induction to levitate it in a vacuum. But it's a lot harder to make than anti hydrogen, Anti helium can be made in a fussion reactor using anti hydrogen as the raw material and many steps further on you can end up with lithium.

While anti-lithium might be storable in visible amounts for an extended time it's production is very wasteful at every stage.


There are accounts of some of the lead atoms in a Russian nuclear powerstation having been converted to gold. If you can imagine trying to make a wedding ring by getting all the lead shielding in every reactor on the planet and not just melting it but boiling it off to get at the gold. And repeat this many times to get enough for the ring and then you realise that the ring is radioactive. Anti matter production is not eco friendly !

oneofakind32

Im also reading Angles and Demons right now and was wondering if anyone knows anything about ''TheoPhysics''? Its supposidly using sphysics to prove religion. I could find very little about it on online

Panserborn

Capt'n Midnight wrote:

There are accounts of some of the lead atoms in a Russian nuclear powerstation having been converted to gold. If you can imagine trying to make a wedding ring by getting all the lead shielding in every reactor on the planet and not just melting it but boiling it off to get at the gold. And repeat this many times to get enough for the ring and then you realise that the ring is radioactive. Anti matter production is not eco friendly !

The old world of alchemy was right! They were just way ahead of their time!

THE FAN

I work in IMEC a major research facility for my final year project and they as far as i am told use positrons to examine pore size of barriers on Sio2 substrate> it is fired in and its life time determines the pore size, so anti matter is real but actual anti atoms are as of yet impossible to store but indivudial particles that are charged are "readily used.

nesf

Intersting sig.

Edit: Oh and, PET scans btw.

themole

nesf wrote:

Scientific American had a good article this month on antimatter and the recent advances and creation of anti-atoms.

Linkage for people who don't buy it here

i presume you mean this article:
Title: Making Cold Antimatter.
Authors: Collins, Graham P.
Source: Scientific American; June 2005, Vol. 292 Issue 6, p78, 8p
Document Type: Article
Abstract: Low-energy atoms of antihydrogen will enable researchers to test a fundamental property of the universe [ABSTRACT FROM AUTHOR]
ISSN: 0036-8733
Accession Number: 16962477
Database: Scientific American Archive Online


for those of you in UCD, or possbile other college, they can download all the issues of Scientific American here:
http://www.sciamarchive.org/

nesf

They moved the site.

Never heard of it in my days in UCC. Would have been damn handy though!

themole

access was added september last year.

under some sfi/hea scheme for journel access.

also included access to the journal Science

nesf

themole wrote:

access was added september last year.

under some sfi/hea scheme for journel access.

also included access to the journal Science

Ahh, that would explain it then.

Access to Science, cool, that's useful. There's "full" collections of both in the library, but having net access would be very handy, esp for post grads. Or just curious browser type people.

CiDeRmAn

Aren't particles and anti-particles perpetually being created and destroyed all around us, is that what they said could be happening at the event horizon of a black hole where the pair are seperated from mutual destruction by the barrier and this results in a radiation of excess particles, then reacting with matter around the event horizon, creating detectable energy? Or did I read something all wrong?

Spear

CiDeRmAn wrote:

Aren't particles and anti-particles perpetually being created and destroyed all around us, is that what they said could be happening at the event horizon of a black hole where the pair are seperated from mutual destruction by the barrier and this results in a radiation of excess particles, then reacting with matter around the event horizon, creating detectable energy? Or did I read something all wrong?

The first part is sometimes referred to as the quantum foam or vacuum. When it occurs near an even horizon you get the second part called Hawking Radiation. Hence also why black holes can evaporate away.

Panserborn

CiDeRmAn wrote:

Aren't particles and anti-particles perpetually being created and destroyed all around us

Excuse my lack of physics understanding, I only know what old popular science books tell me. Anyway - my question: when particles hop in and out of existance how does this fit with the "matter can neither be created or destroyed, only converted from one form to another" law?

Spear

Panserborn wrote:

Excuse my lack of physics understanding, I only know what old popular science books tell me. Anyway - my question: when particles hop in and out of existance how does this fit with the "matter can neither be created or destroyed, only converted from one form to another" law?

It doesn't, that law was wrong, though it can still hold true on a large scale or long enough time frame. The sum of the mass's and energies created by a vacuum pair is still zero when considered as a total, and when they mutually annihilate you're back to zero. Taken on a particle by particle case it simply doesn't apply.

CiDeRmAn

Its all too weird to contemplate really!
There are so many things going on following both relativistic and quantum descriptions of the universe that at our scale seem bizarre in the extreme.
Spooky action at a distance, singularitys, space topology, branes, its quite enough to make your brain itch and make one want to have a wee sleep 'til it all goes away.

Panserborn

Spear wrote:

It doesn't, that law was wrong, though it can still hold true on a large scale or long enough time frame. The sum of the mass's and energies created by a vacuum pair is still zero when considered as a total, and when they mutually annihilate you're back to zero. Taken on a particle by particle case it simply doesn't apply.

Can any of the other thermodynamic laws be somewhat "bypassed" like this? For instance, the "entropy is always increasing" law?

Spear

Panserborn wrote:

Can any of the other thermodynamic laws be somewhat "bypassed" like this? For instance, the "entropy is always increasing" law?

I wouldn't have thought that the laws of thermodynamics really applies to a system that wipes out it's own existence.

mindurownbusnes

I am interested thread to know what antimatter is. I am doing a little chemistry research at the mo.

Spear

mindurownbusnes wrote:

I am interested thread to know what antimatter is. I am doing a little chemistry research at the mo.

http://en.wikipedia.org/wiki/Anti-matter

Does a pretty decent explanation.

Capt'n Midnight

BTW only about 1 gramme of matter was converted to energy in the A-Bombs dropped on Japan. ie. the same a a 1/2 gramme of anti-matter being anihilated with the same amount of ordinary matter. By comparison you'd fit about 100g of Plutonium in a level tea spoon.

solas

be gentle with me, my mind goes to places sometimes...

Is it possible that human physiology can produce anti matter?
Now, I know your automatically thinking why would our brains produce anti matter, but I mean in very teeny weeny small doses that could act as a fuel for thought processes or create subjective experiences.

I should explain why I'm asking. Was reading a regular article in a local rag which touches on strange topics occasionally, this week the question posed was it's an ancient human question, one of the toughest ever: how can the material brain, which is an aggregate of nerves tissues and whatnots be capable of subjective experience? Does science have a modern answer

A: Perhaps in another century or two the "exactly how" of this may be adequately answered, though some believe it never will say's harvards Allen Hobson in "13 dreams freud never had"
But the question can be turned on its head to ask how the brain would not be conscious when it has over 100 billion neurons, each oncnected to 10,000 others and firing at rates of 2-60 times every second. The information processed is more than 10^29 bits/second, or 100,000,000,000,000,000,000,000,000,000!

"Thats enough information to support both perception and the perception of perception and enough to support awareness and awareness of awareness." In a word, it's enough to support consciousness, which emerges once the brain reaches a sufficiently high level of organisation.


anyway...I understand that "Antimatter is not found naturally on Earth, except very briefly and in vanishingly small quantities (as the result of radioactive decay or cosmic rays). This is because antimatter which came to exist on Earth outside the confines of a suitable physics laboratory would almost instantly meet the ordinary matter that Earth is made of, and be annihilated." wiki

I was just wondering theoretically, can anyone imagine human biology having the capacity to produce anti matter, which when annihilated becomes a form of fuel for our eh..existance?

Son Goku

solas wrote:

be gentle with me, my mind goes to places sometimes...

Is it possible that human physiology can produce anti matter?

Yes, very short lived antimatter.
Although everything does, human's in particular wouldn't be anything special in this regard.
(Assuming virtual particles have a reality outside the Feynman diagrams)

Permanent anti-matter, no never, I'd imagine.

I was just wondering theoretically, can anyone imagine human biology having the capacity to produce anti matter, which when annihilated becomes a form of fuel for our eh..existance?

Even if we produced it, matter-antimatter collisions produce raw energy as an output. Our brain has no mechanism for using this form of power.

Professor_Fink

Hi,

Long time no see.

Son Goku wrote:

Yes, very short lived antimatter.
Although everything does, human's in particular wouldn't be anything special in this regard.
(Assuming virtual particles have a reality outside the Feynman diagrams)

Actually, they don't have a reality outside Feynman diagrams. At least not in the way you think. It's a way of looking at the different order terms when you quantize a field.

If you add a bit of energy, though, like in the field of an atom for example, then they can have a fleeting existance (being promoted to real rather than virtual particles).

Son Goku wrote:

Permanent anti-matter, no never, I'd imagine.

Even if we produced it, matter-antimatter collisions produce raw energy as an output. Our brain has no mechanism for using this form of power.

I'm sorry to have to call you on this, but it is wrong. There is no such thing as raw energy. When matter and antermatter interact, they tend to produce photons and some other things. Momentum and energy both need to be conserved, and smashing an electron into a positron must yield other particles.

Not everything is matter, only the heavy stuff :-) (I know that you know this , Son Goku, but I thought I'd clear it up for anyone else reading the thread)

Son Goku

Professor_Fink wrote:

Actually, they don't have a reality outside Feynman diagrams. At least not in the way you think. It's a way of looking at the different order terms when you quantize a field.

I don't know. I certainly don't think they're definitely real, but I also don't think they're definitely solely perturbative artefacts. The physical interpretation comes so easily as to make me suspicious. I understand that if we had a more complete knowledge of integrability we would never have actually known about them.
Of course you're an actual Ph.D. student, so your knowledge will be more extensive then mine, I'm still in the early "what does stuff mean" stages of coming to grips with the mathematics of QFT.
I've also only studied QED, so maybe it's more blatant in QCD that their sole reality is as tools perturbative expressions.

Actually, isn't interesting that mathematically QFTs themselves haven't been shown to "exist".
(e.g. Hagg's Theorem, "The interaction picture doesn't exist unless there is no interactions")

Professor_Fink wrote:

I'm sorry to have to call you on this, but it is wrong. There is no such thing as raw energy. When matter and antermatter interact, they tend to produce photons and some other things. Momentum and energy both need to be conserved, and smashing an electron into a positron must yield other particles.

Yeah, lax language on my part. I just wanted to basically say that there is no way for our brain to utilise whats produced (i.e., it's too raw), but I should have phrased it correctly.

What area of physics are you in? You go to Oxford if I remeber correctly.

Professor_Fink

Yes, I'm in Oxford. I'm in quantum information.