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Thread: Antimatter containment

  1. #1 Antimatter containment 
    Forum Freshman Steve Griffin's Avatar
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    I recently read an interesting thing in NASA Tech Briefs...success in extended storage of anti-protons, from minutes (previous record) to weeks. It seems from the design of the "bottle" that weeks were not a limit, either...just had no reason to keep it up longer.

    The stated purpose of the research will appeal to Trekers...or is it Trekies? I know one is considered derogatory, but I forget which one...

    for fuel in matter-antimatter driven spacecraft.


    Dr. Silica

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    The question is, what does it get you in the end? Will a bucket of anti matter and $5 buy you a cup of coffee? Does a sudden mix of matter and anti matter actually do anything cool?


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  4. #3  
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    Quote Originally Posted by (In)Sanity
    Does a sudden mix of matter and anti matter actually do anything cool?
    I thought it was supposed to cause some kind of explosion or implosion... something bad.
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  5. #4 Anything Cool? Are you kidding? 
    Forum Freshman Steve Griffin's Avatar
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    My God! What are they teaching in science classes these days?

    I assume that you are familiar with E=MC^2, where E is energy, M is mass and C is the velocity of light (300,000,000 meters per second). This equation accurately predicts the amount of energy released when matter is converted into energy and vice versa.

    The units are mass in grams and energy in Joules (one watt is one Joule/second). Since the velocity of light is a large number and this is squared, even tiny amounts of matter converted into energy releases massive energy. This is how nuclear weapons work, but in nukes, only a tiny fraction of the fissionable or fusionable material is converted into energy in the transmutation of one element to another. Nukes are extremely inefficient in comparison to matter/antimatter.

    In matter/antimatter reactions, 100% of the mass is converted into energy so if you combine 50 grams of matter with 50 grams of antimatter you get 9,000,000,000,000,000 Joules of energy. That, my friends, is a lot. In fact, it is more energy than released by burning about a million gallons of rocket fuel, and it weighs a hell of a lot less.

    So, matter antimatter is the perfect fuel for space travel since you get huge energies without having to accelerate lots of fuel mass.

    Does it do anything cool? What a question!
    Dr. Silica

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  6. #5  
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    I just assumed it was Star Trek crap, have they tested this yet?

    So how does one get the two to mix without the anti-matter converting back?

    I can see it now, the anti-matter bomb. "When it really doesn't matter, use anti-matter."
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  7. #6 good one 
    Forum Freshman Steve Griffin's Avatar
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    Like your ad copy for the bomb!

    As to antimatter converting back, you get one big "HUH?" from me. Antimatter does not convert to matter, it annihilates matter. The problem is that it will annihilate ANY matter that it comes into contact with, which is why one needs the magnetic and static electrical field “bottle” to contain it. To produce energy, all one need do is stop containing it and WHAM. The “trick” would be to make sure that the first matter that the antimatter encounters is within a chamber designed to direct the energy and to make sure that the antimatter leaks into the reaction chamber slowly, to control the energy release. These problems are relatively simple to solve, using existing magnetic field technology akin to that used in mass spectrometers. The BIG problem has always been storage. Well, there is another one: making antimatter is no mean trick either. It is naturally occurring, but there is no mine on this planet.

    As to the Star Trek science…a great deal of the technology used in the series is based upon extrapolations of known technology and very well may come into fruition in our lifetimes. The RESULTS of the technology are the fantasy, e.g. faster than light travel does happen just because you have matter/antimatter propulsion.
    Dr. Silica

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  8. #7  
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    The BIG problem has always been storage. Well, there is another one: making antimatter is no mean trick either. It is naturally occurring, but there is no mine on this planet.
    So, if this happens in nature and of course it's not contained then what happens when it encounters matter? I mean it would sound like we would have little bursts of energy at random all over the planet.
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  9. #8 the air force wants it 
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    Air Force pursuing antimatter weapons / Program was touted publicly, then came

    http://sfgate.com/cgi-bin/article.cg...NGM393GPK1.DTL
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  10. #9  
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    There are very probably tiny bursts of energy all through the universe, and some not so tiny, due to naturally occuring matter/antimatter reactions.

    As to the USAF program, it will also be advanced by the latest "breakthrough" in containment, but one must keep in mind that containment requires considerable and continuous energy to be applied to the containmnet field and even minor disruptions have catastrophic results...this is not technology that I would be terribly worried about being deployed in the Gulf...
    Dr. Silica

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  11. #10  
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    If you are really interested in anti-matter, I suggest reading Dan Brown's prequel to The Da Vinci Code, it's called Angels & Demons. It's just as good at Da Vinci Code, with the same main character. As always, I strongly endorse what Dan Brown claims in his book (besides the actual fictional story and characters). Brown researches his books to an extend not many understand. In Angels & Demons he talks about anti-matter, CERN (which is a real company), and an anti-matter bomb. Interestingly enough, it also deals with the Vatican and a new pope, but thats just part of the fictional side.
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  12. #11 Da Code 
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    CERN is not a company of any kind. It is the world's largest facility for the study of particle physics with BIG particle accelerators (atom smashers to you lay folks), akin to the Stanford Linear Accelerator Center near San Jose (for you Californicators), but bigger.

    As for the rest of your message, Huh? I thought this was a science forum, not a para-science forum.
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    So, if this happens in nature and of course it's not contained then what happens when it encounters matter? I mean it would sound like we would have little bursts of energy at random all over the planet.
    Antimatter is very rare.
    Which is interesting.
    The reason why this is interesting is that in a more homogenous big bang, then equal amounts of matter and antimatter would have been formed and would have pretty much annihilated each other completely out of existence by now. (Soon after the big bang, in fact.)

    Instead, what happened was that more matter than antimatter was created and thus after the war of annihilation, there was still matter left over. And a whole mess of radiation (from other sources as well.)


    Now. The question is how much antimatter did survive those early days when everything was so close together? Might there be antimatter galaxies out there? That'd be a hell of a bang if an antimatter galaxy collided with a matter galaxy. In most galactic collisions, there is very little contact between large bodies in the galaxies, instead it's more like a mixing of the dust and gas which kick starts star formation in a big way. But generally leaving the two galaxies somewhat intact afterwards. But, in the case of a matter/anti-matter collision. BOOM! The dust and gas mixing wouldn't create stars but massive amounts of radiation which would likely cause a jostling that would cause far more sun to sun collisions. Or at least that's what I'm thinking. I wonder if there's ever been any mathematic simulations of such a thing?
    Hmmm.


    Anyway.
    Antimatter is actually constantly being formed as quantum fluctuations.
    Particles and antiparticles pop into being and promptly annihilate each other leaving a net charge of 0. Except in the case of when they form near black holes and the anti-particle is drawn into the black hole and the particle is ejected. This is hawking radiation and explains the dwindling of black holes over time. (Actually, the real explanation is far more mathematical than that, I've been told. And the particle/anti-particle thing isn't even hinted at by the calculations. But it is the common method of explaining it. Would be nice if some of our physics gurus would show up. I've been wanting to ask about this.)


    I recall Piers Anthony using Anti-Matter in his Bio of a Space Tyrant series. He used iron so that it could be easily manipulated using magnetism. I take it that this new method removes the need for the anti-substance to be magnetic? What element is it? Hydrogen?
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  14. #13  
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    Quote Originally Posted by invert_nexus
    I recall Piers Anthony using Anti-Matter in his Bio of a Space Tyrant series. He used iron so that it could be easily manipulated using magnetism. I take it that this new method removes the need for the anti-substance to be magnetic? What element is it? Hydrogen?
    I believe they just suspend the anti-protons and run them around in circles using electromagnets. A lot like the containment system in a fusion reactor.
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    As far as I can see there can be no useful matter/antimatter device unless we could find an actual hunk of anti-matter which could be (very, very carfully!) mined. Otherwise the only antimatter we can produce (for use as a fuel) is by using the ginormous amount of energy that will be yielded by the matter/antimatter reaction, in fact more probably many many times more. Unfortunately, it's not likely that such a resource would ever be found, particularly not in our solar system.
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  16. #15  
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    Quote Originally Posted by Silas
    As far as I can see there can be no useful matter/antimatter device unless we could find an actual hunk of anti-matter which could be (very, very carfully!) mined. Otherwise the only antimatter we can produce (for use as a fuel) is by using the ginormous amount of energy that will be yielded by the matter/antimatter reaction, in fact more probably many many times more. Unfortunately, it's not likely that such a resource would ever be found, particularly not in our solar system.
    Let me see if I get what your saying. You expect to find a large chunk of antimatter stuck in the side of a hill someplace surrounded by normal matter, hmm. If you said floating in space I could go with it, but not anywhere we would be mining it

    Booom!!! That's all I can say.
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  17. #16 wow, the discussion takes off!!! 
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    OK, lots of action in a short time -- like a M/AM meet. I like the matter/antimatter galaxy collision and agree that it would very probably be more eventful than the humdrum collisions we've all seen before But how much more eventful, that is the question and while I apreciate your "gut" feelings that the dust interactions would stir the pot enough to really make things go, I think the opposite is more likely -- that the initial interactions would begin to repel the collision and the entire thing would stop.

    Could go either way or half between, i suppose, but as to calcuating the enormity of the POTENTIAL, well I doubt if a googleplex would be sufficient.

    Where did the antimatter of the big bang go? is my query. I have not seen a treatment that adequately explained the imbalance at creation, but I have seen radio images of the "universe" that indicate there is a huge imbalance of matter in space -- hardly uniform distribution -- so escaping matter and antimatter collisions in the first seconds does not seem all that implausible.

    As to Hawking radiation -- good treatment: simple, to the point. Do you teach for a living? Or is that you, Stephen?

    Hum, what else -- ah, yes. Mining need not be terrestial. We can mine the meteors with the right equipment. Why not antimeteors? But barring a boon like that (Bill Gates' wealth is meaningless in comparison to a meteor or AM), the price for producing AM is very well worth it as a fuel where the mass is the problem (see beginning of thread).

    And finally, you are right, it is currently antiprotons that are made, exclusively. The containment of youre was mere magnitism and the AM only could be stabilized for short periods...very, very, very short...when the protons random non-symmetrical Brownian motions coincide enough to slip out and POOF!

    The breakthrough reported in NASA Tech Briefs is coupling electrostatic and magnetic bottling (if I recall correctly -- it has been a couple of months since I read it) with both fields rotating or one...memory slips with age...

    But the result was, again, WEEKS of containment...

    But antimatter ain't all that is missing from this universe, by far. There is missing matter, too...more than we do know if, at that.
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  18. #17  
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    Quote Originally Posted by Locke
    If you are really interested in anti-matter, I suggest reading Dan Brown's prequel to The Da Vinci Code, it's called Angels & Demons. It's just as good at Da Vinci Code, with the same main character. As always, I strongly endorse what Dan Brown claims in his book (besides the actual fictional story and characters). Brown researches his books to an extend not many understand. In Angels & Demons he talks about anti-matter, CERN (which is a real company), and an anti-matter bomb. Interestingly enough, it also deals with the Vatican and a new pope, but thats just part of the fictional side.
    Bought it yesterday. First of all, I can't help noticing that it begins exactly the same as The DaVinci Code. In a prologue, someone has a secret and is in the process of being killed for it. In the first chapter, Robert Langdon is in a hotel and is woken at an ungodly hour by a telephone call from a mysterious person who wants his help. I think Brown has a plot-generating program which is evidently stuck.

    I stepped back a few pages to a page marked FACT. I'm wary of these, because there was a page of such FACTs at the end of one of Stephen Baxter's novels, and all the facts he mentioned were things that I understood entirely to be facts from his book, and why make a big deal out of it? Well, Brown's FACTs are no different.

    FACT

    The world's largest scientific research facility - Switzerland's Conseil Européen pour la Recherche Nucléaire (CERN) - recently succeeded in producing the first particles of antimatter. Antimatter is identical to physical matter except that it is composed of particles whose electric charges are opposite to those found in normal matter.

    Antimatter is the most powerful energy source known to man. It releases energy with 100 per cent efficiency (nuclear fission is 1.5 per cent efficient). Antimatter creates no pollution or radiation, and a droplet could power New York Ciy for a full day.
    There is, however, one catch....

    Antimatter is highly unstable It ignites when it comes into contactwith absolutely anything...even air. A single gram of antimatter contains the energy of a 20-kiloton nuclear bomb - the size of the bomb dropped on Hiroshima.
    If I never again read such a farrago of ill-understood physics and misleading statements posing as "FACT" it will be too soon. I mean, "Even air"
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    Insanity, you actually did entirely misunderstand me. I was referring to a hunk floating in space, yes. If we find a hunk of antimatter floating in space (not likely, in case you thought I thought it was), we would mine it. We would obtain the antimatter from it, which would be the equivalent of extracting a resource from our planet, ie mining it. My use of the word "mine" was not meant to imply that the antimatter was on Earth surrounded by matter, an impossible situation as I am aware of as much as you.
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  20. #19  
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    Quote Originally Posted by Silas
    Insanity, you actually did entirely misunderstand me. I was referring to a hunk floating in space, yes. If we find a hunk of antimatter floating in space (not likely, in case you thought I thought it was), we would mine it. We would obtain the antimatter from it, which would be the equivalent of extracting a resource from our planet, ie mining it. My use of the word "mine" was not meant to imply that the antimatter was on Earth surrounded by matter, an impossible situation as I am aware of as much as you.
    "Mine" may have been better expressed with "Collect". Mining in space still implies extraction from within some other solid object.

    Would be pretty wild if we had basketball sized pieces of antimatter floating around in space, once in a while impacting matter at high speeds. I'm not sure, but I think the resulting impact would be extremely powerful. How about an anti matter comet.
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    "Mine" may have been better expressed with "Collect". Mining in space still implies extraction from within some other solid object.
    Sure. A radio controlled antimatter robot.

    There could also be other methods to extract antimatter from a natural source as well, I'm sure. Most science fiction treatments of antimatter powered devices treat the antimatter as a created object. Passed through an artificial singularity or some such (I'm not saying that this will make antimatter so don't go disputing it. This is just one of the methods I've seen in scifi). But, that doesn't mean that mining (or collecting, semantics) from a natural source is impossible. Use your imagination.
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  22. #21  
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    Quote Originally Posted by invert_nexus
    "Mine" may have been better expressed with "Collect". Mining in space still implies extraction from within some other solid object.
    Sure. A radio controlled antimatter robot.

    There could also be other methods to extract antimatter from a natural source as well, I'm sure. Most science fiction treatments of antimatter powered devices treat the antimatter as a created object. Passed through an artificial singularity or some such (I'm not saying that this will make antimatter so don't go disputing it. This is just one of the methods I've seen in scifi). But, that doesn't mean that mining (or collecting, semantics) from a natural source is impossible. Use your imagination.
    Well I suppose we could Mine a small piece from a larger piece. The question is how would one do so. Matter and anti matter don't like to mix, so if we had an antimatter rock floating around using matter based mining tools on it would sound kind of dangerous. Correct me if I'm missing something.
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    if we had an antimatter rock floating around using matter based mining tools on it would sound kind of dangerous.
    A radio controlled antimatter robot.
    Antimatter is just like regular matter. Only backwards. You could construct anything you wanted from antimatter. Mining tools galore.

    The question would be how to begin. There could be various methods of manipulating antimatter with enough precision to make simple robotic tools that could then be used to create more complex robotic tools that could create even more complex tools. Don't ask me methods, cause I don't have any. But it could be done.

    Necessity is the mother of invention.

    (Isn't Star Trek based on mined antimatter? Dilythium? Is that antimatter or is it used to create antimatter? I've never been a star trek nerd. My nerdishness lies in other areas.)
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  24. #23  
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    Quote Originally Posted by invert_nexus
    A radio controlled antimatter robot.
    Antimatter is just like regular matter. Only backwards. You could construct anything you wanted from antimatter. Mining tools galore.
    I understand your theory, but I'm not really sure it can be done. The thing is that anti-matter is just that, the opposite of matter, it's not a solid thing. We can't make anything out of antimatter because we can't touch it with anything other than magnetic fields. You can't raio-control it because that would require antimatter to be...well matter.
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  25. #24  
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    Locke,

    The thing is that anti-matter is just that, the opposite of matter, it's not a solid thing.
    Uh. No. You've got mistaken ideas about antimatter obviously. Not surprising considering where you've derived your knowledge of it from.

    If you lived in an antimatter universe, you wouldn't be able to tell the difference between that universe and this universe. The only difference is in polarity of elementary particles but that doesn't mean crap to how you perceive or work with the world.

    In fact, I don't think that there would even be a way to determine if the Andromeda Galaxy (which is hurtling towards us on a collision course) is matter or antimatter. Not by visual means, surely. Perhaps there are other means that I'm not aware. I'm far from an expert.

    Electricity would most likely be changed. Instead of electrons it would utilize positrons. And several other technologies would require modification as well. But they could all be worked out.

    We can't make anything out of antimatter because we can't touch it with anything other than magnetic fields.
    This would be the biggest problem. The initial construction of the simple robotic devices. However, I have no doubts that something could be worked up to accomplish this. Consider a society advanced enough to use antimatter as a power source. There would be a whole technology of antimatter containment fields and manipulation fields. It would be necessary for the technology to be viable at all.

    So. As I've said, I don't have the technical methods but am rather taking them for granted. It's an old sci-fi ploy, you know. Think 'hyperspace'.

    You can't raio-control it because that would require antimatter to be...well matter.
    Uh. Yeah you can.
    Stop getting your physics knowledge from a religious hack.
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  26. #25  
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    I don't know which religious hack you are refering to, and I don't really care. I based my knowlege of anti-matter from what I've seen on CERN's website and other internet sources. Where are you getting your information from?
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    At the risk of making Invert even angrier at me, I'm going to reiterate my argument. Even if we could, as Invert keeps violently trying to explain to me we could, create an antimatter 'robot' it would be of absolutely no use to us. Nothing on earth made out of matter (AKA everything) could touch the robot nor what it has 'mined' from whatever source. The only way I can think of is if that 'robot' put the antimatter into a gravitational field and sent it to earth, although I don't know how that robot could do that because the containter would have to be made out of matter, would it not cost less for us to just make antimatter the way we are already doing? I just don't see how having antimatter anything could be any use to us except to be a danger to anything that it's around.
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  28. #27  
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    Quote Originally Posted by Locke
    At the risk of making Invert even angrier at me, I'm going to reiterate my argument. Even if we could, as Invert keeps violently trying to explain to me we could, create an antimatter 'robot' it would be of absolutely no use to us. Nothing on earth made out of matter (AKA everything) could touch the robot nor what it has 'mined' from whatever source. The only way I can think of is if that 'robot' put the antimatter into a gravitational field and sent it to earth, although I don't know how that robot could do that because the containter would have to be made out of matter, would it not cost less for us to just make antimatter the way we are already doing? I just don't see how having antimatter anything could be any use to us except to be a danger to anything that it's around.
    It would need a magnetic containment docking station. This would suspend it and it's cargo for transport. It would never touch matter. Just don't sneeze
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  29. #28  
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    Quote Originally Posted by (In)Sanity
    It would need a magnetic containment docking station. This would suspend it and it's cargo for transport. It would never touch matter. Just don't sneeze
    Yeah, I guess you could work out a way to do it. I just don't think that it would be worth the risk having antimatter and matter working in such close proximity to each other.
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    Locke,

    I don't know which religious hack you are refering to, and I don't really care.
    "If you are really interested in anti-matter, I suggest reading Dan Brown's prequel to The Da Vinci Code, it's called Angels & Demons." -Locke

    It was you who said this, right?
    And. You do care.

    I based my knowlege of anti-matter from what I've seen on CERN's website and other internet sources.
    I think I know what your confusion is. (Hint: I'm giving you a means to save face.)

    The antimatter under discussion is not really antimatter. It's anti-protons. Anti-matter would be an anti-proton and neutron core (I think that it uses regular neutrons... not entirely sure about that) with a positron cloud around it.

    It's identical to matter with the single change of the charge differences.

    There is a possibility that different isotopes might be likelier to form in an anti-matter universe as opposed to a matter one, but the anti-matter goes through all the same elements that matter does.

    Hydrogen, Helium, Carbon, Oxygen, Iron, Uranium. All of the elements would be represented in the anti-matter universe just as they would in the matter universe.

    Anti-matter is matter. Just matter composed of elementary particles of an opposite charge.

    (Know what I'd be interested in? What about quarks? How do they differ?)

    Anyway, your confusion is thinking that anti-matter is what is being trapped in the CERN trap. What they have is the elementary particles of anti-matter.

    I could easily see an anti-matter person having the same argument about matter not being solid for the same reasons.

    Where are you getting your information from?
    I actually am posting to you from an antimatter universe.
    Kidding.

    Here and there. I don't recall any specific sources, but I've read several books which touched upon anti-matter down the years. And I'm not talking science fiction books. I've already said I'm no expert, but I am sufficiently sure of my knowledge in this. If I'm shown to be wrong, then so be it. I'd prefer knowing the truth than hanging on to false knowledge through pride.

    Edit:

    as Invert keeps violently trying to explain to me we could
    Violently?
    God, you're a pussy.

    Yeah, I guess you could work out a way to do it. I just don't think that it would be worth the risk having antimatter and matter working in such close proximity to each other.
    Yeah. I guess you could figure out a way to do it.
    And the dangers are well known and would have to be weighed against the benefits and the technology available to harness that potential.


    Steve Griffin,

    I think the opposite is more likely -- that the initial interactions would begin to repel the collision and the entire thing would stop.
    I had the same thought. But, on the way out of the collision area, the various bits and pieces would collide even more.

    I suppose it all comes down to how far the two galaxies could intermingle before the reaction began, and I suppose the answer to that would be practically nill. In the case of young galaxies, the reactions might even begin before the disks touch. As the bits in the halo touch. At least as soon as the gaseous disk began to touch. So, it might act to drive the galaxies apart again.

    But, consider the force necessary to move a galaxy. These are huge things pushing towards each other at immense speeds. I suppose much of the calculation would have to consider the weight of the dust and gas (which would be the prime reaction agents) with the weight of stars and planets. Would the power derived from the dust and gas reactions be enough to divert the more solid aspects of the galaxies?

    I have the feeling that this would be the old "irresistable force vs. the immovable object" scenario. It'd definitely be a sight to see.... from a nice safe distance. Surely someone has done computer simulations of such an event. Must search.

    And, in the case of old galaxies with the dust and gas already used up, they might go whizzing through each other with only the barest hints of collisions.

    Where did the antimatter of the big bang go? is my query. I have not seen a treatment that adequately explained the imbalance at creation
    Me neither. It all comes down to random chance, basically. Miniscule fluctuations in the early universe spreading out to larger scale fluctuations. Chaotic effects.

    so escaping matter and antimatter collisions in the first seconds does not seem all that implausible.
    It's been awhile since I've read into this area, but matter didn't form until later than a few seconds, right? Or was it just a few seconds? I know that it functions on a logarythmic scale, but I forget when matter formed. And I'm too lazy to go looking for it right now. It's not really necessary for the discussion.

    As to Hawking radiation -- good treatment: simple, to the point. Do you teach for a living? Or is that you, Stephen?
    Ha.
    Stephen Hawking? Not even.
    No. I don't teach. As I said, that was the common popular science explanation for Hawking Radiation, but the real explanation centers wholly around math and doesn't really translate into the physical in such a neat, orderly manner. I wish some physics gurus were around to explain it in their own words.

    But antimatter ain't all that is missing from this universe, by far. There is missing matter, too...more than we do know if, at that.
    Don't look at me. I didn't take it.
    Heh. Yeah. There's a lot of unfinished business in this explaining business.
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    Yeah, I think you are right about matter forming after some time...can't recall how long either, though. The longer ti was, however, the more plausible the escape from collisions proposition becomes since the expansion was very rapid and 1/r^3 helps prevent interactions a great deal.
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    Anti-matter is very hard to come by in this galaxy. It would cost billions of dollars just to conger up a small amount of it. Sometimes I wonder if maybe there are galaxies out there composed of anti-mater.

    Could you imagine what would happen if one of these theoretical anti-matter galaxies collided with a galaxy composed of matter?
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    Could you imagine what would happen if one of these theoretical anti-matter galaxies collided with a galaxy composed of matter?
    Gee can we say "Big Bang"
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    Quote Originally Posted by invert_nexus
    The antimatter under discussion is not really antimatter. It's anti-protons. Anti-matter would be an anti-proton and neutron core (I think that it uses regular neutrons... not entirely sure about that) with a positron cloud around it.

    It's identical to matter with the single change of the charge differences.
    Ah, that's actually something incorrect that Dan Brown says! If antimatter were identical to matter with the single difference of charge direction, then how is it that matter and antimatter mutually annihilate? No, the charge difference is merely the most obvious sign that what you have is an antiproton or a positron. Despite being chargeless, there are antineutrons, too. The "equal and opposite" property of the anti-neutron can best be described as "that which will mutually annihilate with a neutron".

    Also, you're a little incorrect. Matter is not "that which is made of atoms", matter is that which is matter as opposed to energy; that which has mass; and consequently includes all protons, neutrons, electrons and other particles.
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    [quote="Silas"]
    Quote Originally Posted by invert_nexus
    The antimatter under discussion is not really antimatter.
    Yeah I wouldn't compare Invert_Nexus to Dan Brown, I don't think he's a fan.
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    That's why I was at pains to put him right.

    I'm sorry, Locke, but I'm just barely getting through this book, there is scarcely a page on which DB doesn't just make me laugh out loud. The idea that the director of CERN would be disbelieving, shocked and amazed that someone created antimatter from streams of pure energy is nothing less than ignorant, in fact it's totally idiotic. As is (although I lean towards science more than the arts) the concept that there could exist a highly educated man, an arts major, sure, but a Harvard Professor, who would a) have never heard of CERN, b) be unaware until told that they have a particle accelerator there in the form of a kilometers-wide ring, and c) that matter and energy are equivalent would apparently be news to him! I can see why the daughter of an RC priest-scientist would make a statement like "When the Catholic Church created the Big Bang theory" (factually incorrect as that may be - its first espouser may have been a Catholic monk, that does not make it the discovery of the Catholic Church), but there is no way in hell this distortion would be endorsed by a highly placed scientist like Kohler.

    He's no better on the arts side. DB's statement that "symbologists had struggled in vain for years to make an ambigram from the word Illuminati and had declared it impossible" is patently nonsensical, particularly when he has just shown you what it looks like, and you can see how easy it is to do. I really don't know how he ever got this book past a remotely competent publisher's reader.
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    Hehe, well you see, when I read it, I was a lot more ignorant than you in the matters that he was talking about. I took it as total fiction, and so I enjoyed it so much. I didn't really stop and say, hey that can't be right. Just try to pretend you know nothing about....well anything.
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    But what annoys me about Dan Brown is that he gets this stuff published, and then someone whose opinion you formerly respected states that the guy did "phenomenal research"! Anyway, this is all by the by and totally off topic, I'm willing to close the subject.
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    Quote Originally Posted by Silas
    But what annoys me about Dan Brown is that he gets this stuff published, and then someone whose opinion you formerly respected states that the guy did "phenomenal research"! Anyway, this is all by the by and totally off topic, I'm willing to close the subject.
    Lol, maybe they were just trying to get onto the back of the book...assuming they actually read the book...hehe.
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    Silas,

    If antimatter were identical to matter with the single difference of charge direction, then how is it that matter and antimatter mutually annihilate?
    Of course there are differences, but what differences? I'll admit that I generalized a bit much in saying they are identical. I mostly meant in appearnce. The fact that they mutually annihilate is not evidenced in their appearance, is it? I suppose there must be some way of discerning matter from antimatter otherwise we wouldn't be able to say there's more matter than anti-matter in the universe. But, is it done with the naked eye? If so, how? What does anti-matter look like as opposed to matter?

    Another thing I was saying (basically my main point refuting Locke's idea of anti-matter being some type of formless nothing), is that anti-matter behaves like matter in that it forms into various elements. (Thank you for telling me about anit-neutrons, I wasn't sure about that at all. An opposite neutral charge... see? That's interesting. Now. What about the quarks? How do they differ?) Anyway, they from elements just like matter does. Some would be gaseous, some would be liquid, some would be solid. All these would be states of the elements at various temperatures. They obey laws of physics. They have properties which would show themselves apparent. Some would be metallic. Some would be flammable. Etc...

    The question, I suppose, is how similar would they be? Would anti-hydrogen behave identically with hydrogen? Would anti-copper conduct electricity (posicity?) in an identical manner as copper? What about isotopes? Would different isotopes be more common in an anti-matter universe?

    I fully realize that there are differences. But at the same time there are similarities. And these similarities are vast while the differences (as far as I know) are few. In an antimatter universe, you could go billions of years without ever seeing matter. So, these differences evidenced by mutual annihilation wouldn't be seen. Right?

    Matter is not "that which is made of atoms", matter is that which is matter as opposed to energy; that which has mass; and consequently includes all protons, neutrons, electrons and other particles.
    Heh. Yeah. I know this too. In fact, I was even thinking of this after I posted. Again, it was because of the argument that I was contradicting. Locke was stating that anti-matter wasn't solid (i.e. matter) so I was sort of using matter in a more general sense of being solid matter. Yes. Protons are matter. They're particles. But they're not solid seeming. They can't even be seen with the naked eye. According to Locke's earlier viewpoint, protons wouldn't be matter. But, then again, neither would Oxygen or Hydrogen...

    So. Think solid. In this sense, even anti-matter (some types) are matter. I know. I know. Crappy semantics. Sue me.
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  41. #40 back to the original notion 
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    This thread originated with my bringing up the success at NASA in extending antimatter containment by orders of magnitude, limit unknown, as promising for a highly efficient fuel for space travel. That it evolved into a discussion of particle physics and pseudo-religious quackery is understandable.

    But another news snippet adds to the original -- the last issue of Chemical and Engineering News has a brief article describing discovery that low level H2S (50ppm or so) induces reversible stasis in mice, where their metabolic rate is dropped by 90%. That is oxygen consumption drops 90%, energy requirements drop 90%, and in theory, aging drops 90%. The discovery is to be studied for stabilizing/postponing patients for surgery or therapy, (slows the growth fo tumors, stabilizes metabolosm awaiting organ donation as well as stabilizes organs for longer viability in transport for transplantation) but could well apply to long space flights.

    The future is now, my friends!
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    invert_nexus, I did understand that what you were actually combatting was Locke's misapprehension about the potential solidness of antimatter.
    Of course there are differences, but what differences? I'll admit that I generalized a bit much in saying they are identical. I mostly meant in appearnce. The fact that they mutually annihilate is not evidenced in their appearance, is it? I suppose there must be some way of discerning matter from antimatter otherwise we wouldn't be able to say there's more matter than anti-matter in the universe. But, is it done with the naked eye? If so, how? What does anti-matter look like as opposed to matter?
    I just didn't express myself very well. I believe there is no evidence in the "appearance", and the only difference in behaviour arises from the opposite charge if there is one present. The only way of knowing that you have an anti-particle is if it annihilates a particle, and then you've lost both of them. But this mutual annihilation based on nothing more than "anti-ness" if you think about it, almost takes on a mystical or magical dimension, doesn't it? I never really thought about it like that before, I just took on board the fact that matter and anti-matter mutually annihilates, creating pure energy out of pure matter. But it's weird to actually think about it happening like that.

    Antimatter frequently gets explained on science TV programs with the presenter looking at a mirror image of himself, and says something like, "If I were to shake hands with my anti-self over there, the explosion generated would......" It makes it sound like a whole object is annihilated by its anti-object. Also it makes it sound like there's an entire anti-Universe exactly the same as this one, with an invert_Silas .... and a Nexus. (:P). What would actually happen I suppose is that the cloud of electrons which form the front line of every surface would interact with the cloud of anti-electrons, and the energy generated from that alone would suffice to reduce the participants to gas - ionized gas, of course, whereupon the freed protons and anti-protons would whoosh together and cause a second 1,836 <sup>2</sup> times as great explosion.
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  43. #42 OK, so it's wierd... 
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    Yes, electrons and positrons have different charge, but the differences are total, not just charge. What is that total? Well, to answer that question we have to know what an electron is and that is a really tough question. So we have to settle for the "mirror image" analogy, for now. Alternatively, CERN describes forming an electron-positron pair from high energy collisions as stamping a coin from sheet metal...the coin can be though of as the electron and the hole the positron. Combine them and you are back to sheet metal (vacuum).

    As to antimatter being exotic, I disagree completely since I have had it formed in my own brain. It is called a PET scan. Positron Emission Tomography. Radioactive decay of a drug given before the scan supplies energy to produce electron positron pairs that then annihilate and release gamma rays that are detected for imaging...or so the technician explained (badly). I wanted to know what the mechanism for the image contrast was...but never got around to searchin it out, figuring it was differential uptake of the radionuclide and let it go.
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    My God - you've got positrons in your brain? You're a ROBOT!



    (I hope it wasn't me that implied that antimatter was exotic. Dan Brown evidently thinks so, since "CERN recently succeeded in creating the first particles of antimatter" )
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    I prefer the term Cyborg...we automatons find the term "robot" offensive.
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    Can antimatter ever be used as a form of rocket fuel instead of liquid oxygen? It seems nuclear power is now a possibility for rocket fuel, but surely if there is an accident with a spacecraft then there will be major problems with radiation globally? Will it ever happen?
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    Even better can matter/anti matter be used to counteract the forces of gravity making mass not exist yeilding a break in the law of e=mc<sup>2</sup>
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    It could do, but we have a long way to go before we can do that. The first step is being able to store antimatter for long enough.
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  49. #48 rocket fuel 
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    Antimatter is the ideal rocket fuel, which was the initial subject for this topic: I had read in NASA Tech Briefs of a simple solution to long-term antimatter containment which had been a HUGE problem with respect to using antimatter as rocket fuel. Sure, there are other problems, like it is terribly expensive to produce, but matters of economics are not "deal breakers" where matters of physics are. In short, there is no remaining major, physical obstacle to stop the use of antimatter as a rocket fuel any longer.

    The advantages are massive (pun)...in that the mass of fuse required to propel a ship is many, many orders of magnitude less than for standard, chemical fuels and even orders less than nuclear fuels. There is no long-lived radiation issue. The gamma rays that are produced in matter/antimatter reactions are EM, not particulate, so once emitted, that is it, and they fall off in intensity with the cube of the distance, so once the ship is at any appreciable altitude, there is no long-term risk to the Earth environment. In fact, one could use standard solid chemical boosters to lift the ship high enough for safety before kicking-in the M/AM engines...

    But the best bet is to build such a ship in space in the first place and, better yet, generate and store the anitmatter fuel in space as well (or take small amounts up with each routine trip to the space station).

    This potential, coupled with the recent discoveries that N2O can produce a fully recoverable, stasis-like condition in mammals, offers the possibility of missions to other stellar systems, if not planetary systems. The practical limits of the distance one can travel depends mostly upon the maximum speed one can attain in the trip. If it is 0.10 C, with relatively constant acceleration to reach that speed, even Alpha Centauri is fairly impractical. (Average speed would be roughly 1/2 of 0.10 C (or about 33.5 million miles per hour which is roughly 1000 times escape velocity), which is a fantastic speed -- but at ~4.5 light years distant, the round trip would take about 180 years. While this, in and of itself, may not preclude making such a trip, getting folks to pony-up hard-earned duckets to fund something that can not possibly give them any benefit in their lifetime is economically difficult.)

    But then, we guage such things upon the current lifespan of man and this is far from a fixed quantity as well...recent developments in the study of senescence in C. elegans (flat worm), and D. melanogaster (fruit fly), as well as a mammal model (mouse) show that we can manipulatre the aging process in these animals quite effectively, increasing or decreasing their life spans by about an order. If this proves translatable to man, the average lifetime would be increased to almost 800-years making 180 years no such a big deal.

    We live in fantastic times, my friends.
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    Steve,

    This is a very nice thread. I've read the same reports in SciAm regarding the reversible "suspended animation" induced by H2S.
    --------------------------------
    It takes an enormous amount of energy (E= mc<sup>2</sup> plus losses) to make antimatter. I've heard of ideas where you build a giant solar powered accelerator "ring" completely encompassing the sun in close orbit, as an antimatter factory. Might be feasible for an advanced society...

    Insanity,

    There is no reason to expect antimatter to posess "antigravity" if that's what you're thinking.
    Huh?
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    You know, it might have been H2S that I read about in Chem and Eng. News...my old brain is deteriorating...parhaps from too much N2O as a youth...can't remember details like I used to.

    Canadian lab, right?
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    There is no reason to expect antimatter to posess "antigravity" if that's what you're thinking.
    I was thinking if it could be used in some other way to yield such a result. Don't ask me how.

    Correct me if I'm wrong here as this is not really my field. Is it not mass that causes limitations on the speed we can travel. Also is it not gravitational forces that produce mass? In other words if all gravitational forces could be canceled out would it not impact e=mc<sup>2</sup> when it comes to maximum velocity? Enlighten me if I'm off base. In other words if something had absolutely no mass would it not be able to reach beyond light speeds? This would assume that the mass was somehow negated down to zero. Then one has to question what is the mass of light that makes it only able to reach a certain speed.
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    You are WAY off base...

    Mass is gravity independent. Weight is the metric for gravitational effect on mass.
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  54. #53  
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    Quote Originally Posted by Steve Griffin
    You are WAY off base...

    Mass is gravity independent. Weight is the metric for gravitational effect on mass.
    So what is the force that produces mass within an object? For that matter a single atom? Why does mass exist?
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    In other words if something had absolutely no mass would it not be able to reach beyond light speeds?
    A photon has no mass. And it only travels at the speed of light.

    So what is the force that produces mass within an object? For that matter a single atom? Why does mass exist?
    The Higgs Boson, the so-called "God Particle", is conjectured to be the mass-conferring particle in the Standard Model.

    From a recent article in Discover magazine:
    <blockquote>In Weinberg's synthesis the Higgs field is like a sea of molasses that fills all of space. It resists the movement of particles ot varying degrees. The more a particle interacts with the Higgs field, the greater the resistance and the heavier the particle. The symmetry of the standard model is thus restored because mass is no longer seen as an intrinsic property of matter. All elementary particles weigh nothing until they interact with the Higgs field. Variations in Higgs field interactions are the only explanation physicists have for the fact the heftiest known particle weights 200,000 times as much as the lightest one, while photons weigh nothing at all*.</blockquote>

    I haven't really looked much into the Standard Model and particle physics aren't exactly my bag. But this Higgs Boson will be the find of the century if it's ever found.

    To relate this to antimatter, we come back to the constituents of the antimatter. The quarks and things. Are they different than the quarks that make up matter or do they simply have a different spin? How far down does the totallity of difference range? And what effect do these differences have? Does an "anti-Higgs Boson" convey antigravity for regular matter? Unlikely else there would be discussion of antigravity effects from antimatter. So. What does it mean?


    *"Nothing at all." Every time I hear this I think of Ned Flanders in a skin-tight ski suit shaking his ass for Homer and saying, "It feels like I'm wearing... nothing at all... nothing at all... nothing at all..." I think it might have been the episode where Lisa needs braces....
    Anyways...
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    Steve,

    Yep, it's hydrogen sulfide.

    Insanity,

    Our current understanding of gravity is described by General Relativity (GR). Matter (mass) causes the spacetime surrounding it to "curve". Don't try to visualize it, it's impossible. And the curvature of spacetime around a mass changes the way other masses move near it. Not only mass is affected. Light will move differently in the presence of curved spacetime.

    So in that way we really don't think of gravity as a force, but as an effect of matter on the shape of spacetime. Yes?
    Huh?
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    Our current understanding of gravity is described by General Relativity (GR)
    And isn't this sort of a small problem? We're discussing particle physics and then we have to jump over to relativity when we want to talk about gravity. When(if) the Higgs Boson is found, then we won't need to 'switch frames' in this way.
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    Would it not be interesting to find out that a Photon does in fact have mass and that's why it's limited in speed. Would it not also be interesting to find out that there are things all around us traveling so much faster speeds then light that we simply can't detect them
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    Photons DO have mass, just not very much. You all have heard of the particle-wave duality conundrum of light, eh??? Well, particles have mass and we can even show the particle nature of light easily enough for a first-grader to understand it...the device that I first saw that demonstrated this particle nature is called a radiometer. It left a very large impression on my young (at the time) mind and I had one spinning in my window for most of my youth.

    http://www.howstuffworks.com/question239.htm

    But the crux of the problem with the original question is that gravity is no the problem for space travel. Sure, it was a BIG problem in the 1950s but it is not the BIG problem for modern space exploration at all. Once out of the gravity well that surrounds us, the problems are acceleration and deceleration. And the Newtonian equation (that works fine until one approaches relativistic speeds) is F=MA. E=MC^2 is another matter altogether.

    That is, Force = Mass times Acceleration. We want to accelerate and decelerate quickly so mass is THE problem that we can address most easliy. The issue with increasing force is that it generally takes mass to do so...the fuel itself has to be accelerated. Come on, guys, this is not rocket science!

    Antimatter generates HUGE forces from very little matter so it is very attractive as a fuel.
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    Ya I get it Steve, small light ship accelerates and decelerates with ease and can even make a turn or two. So are we still calling the force that makes an object stay in motion inertia, or have they renamed that to something else

    So we don't need to overcome gravity we need to overcome inertia ? Still it seams to me that having a ship that has no mass would be the ideal solution all around. Perhaps a way to fake out the laws. Still if it has no weight then it would also have little to no mass correct? Also until we are 100% sure what gravity is we can't rule out that defeating gravitational forces would not somehow impact the effects of inertia and mass. Possible? I'm referring to 0 G on earth in a vacuum without magnetic levitation. To the best of my knowledge that would require an object that weighs nothing..
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    Steve,

    Photons have no rest mass (i.e. no mass) which is the only mass we're talking about.

    Radiometers do not work by photons "mass" (which they don't have)moving the vanes. The vacuum inside the radiometer is not perfect. Light heats the black side of the vane more than the white side. Molecules of air that contact the black side are heated and so rebound with more kinetic energy, thus imparting a "kick" to the black side.

    Edit:

    Photons have no mass but they do posess momentum:

    p = h/wavelength
    Huh?
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    AH, but I believe that we are now reaching an area of some considerable controversy...

    Stating that photons have no rest mass is kinda cheating in that slowing photons to a stop has only been accomplished very recently (Bose-Einstein trap) and even there, one could argue that they were only 'relatively' motionless since the experimental apparatus was hurtling through space at considerable speed (it ws done on Earth).

    And arguing that the radiometer works by heating vs. rebound also has been its detractors...if this were true, one would think that a bit more air (less perfect vacuum) would make the thing work better since the signal (rotational forces) to noise friction of the bearing) would be larger for more atmosphere, but the opposite is true.
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  63. #62  
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    And arguing that the radiometer works by heating vs. rebound also has been its detractors...if this were true, one would think that a bit more air (less perfect vacuum) would make the thing work better since the signal (rotational forces) to noise friction of the bearing) would be larger for more atmosphere, but the opposite is true.
    Have they not tested one of these in space yet? Where the chance of air is pretty slim. I mean without the glass of course.
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  64. #63  
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    Well Steve,

    A photon has no mass. I'm not willing to debate this even for one more picosecond.

    As for radiometers, there is a critical amount of air - too much and drag prevents the vanes from spinning, too little and the paltry few molecules don't have enough juice to move the vanes.

    In a complete vacuum, with a high enough intensity light source, the vanes would move due to momentum transfer (p=h/wavelength).

    Look at your radiometer. The vanes rotate with the white side forward. Something is pushing on the black side (hot molecules). If it were photons, the black side would absorb them while the white side would reflect them and it would rotate black side forward.
    Huh?
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  65. #64  
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    Quote Originally Posted by superluminal
    Radiometers do not work by photons "mass" (which they don't have)moving the vanes. The vacuum inside the radiometer is not perfect. Light heats the black side of the vane more than the white side. Molecules of air that contact the black side are heated and so rebound with more kinetic energy, thus imparting a "kick" to the black side.
    Crooke's Radiometer gave Maxwell a real headache: How does a light-mill work?
    See also Wikipedia
    The way it works is intricate indeed.

    Nichol's Radiometer, on the other hand, does in fact work by light pressure.
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    Thermal transpiration. Hmmm...

    I think I got it essentially right, right? Sort of... maybe...
    Huh?
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    I concede that the Crooke's radiometer was a poor example and is, in fact, driven by heat. I was remembering observations from childhood...and from one who continues to confuse east and west, reversal of rotationis probably not my major fault.

    BUT photon mass is another issue altogether. Crooke's radiometer may be too crude to show photon mass, but other, more modern devices are capable of showing some mass must exist -- just not precisely how much since it is exceedingly low.

    I'll not conceed that one at all. To state difinitively that a photon has no mass is to ignore a mass of research and publications wrt attempts to narrow the limits on the photon mass...and the implications of there being no mass? Aaarrgghh...mathematically, no mass creates problems from Maxwell forward.
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  68. #67  
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    Steve,

    I would love to see any reputable scientific documents (web site links) that claim or show in any way that photons have mass. I'll wait...

    PS: Maxwell's equations have no terms for mass.
    Huh?
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  69. #68  
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    Dr. Silica

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  70. #69  
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    Quote Originally Posted by Steve Griffin

    http://arxiv.org/PS_cache/astro-ph/pdf/0205/0205331.pdf

    We show that, in a locally-de-Sitter inflationary
    spacetime and in the presence of a light, minimally coupled,
    charged scalar field, the polarization of the vacuum
    induces a photon mass at the one-loop level.
    and,

    Thescalar propagator goes like 1/x2 in 3+1 dimensional
    flat space, and the photon stays massless. In de Sitter
    background the scalar propagator has a logarithmic tail
    which is responsible for our mass generation effect.
    http://arxiv.org/PS_cache/hep-th/pdf/0203/0203271.pdf
    We discuss the impact of a bulk photon mass in a Dvali–Gabadadze–Porrati type brane model with Maxwell terms both on the brane and in the bulk,
    Steve,

    The first paper seems to describe how, in inflationary space (very early universe) vacuum polarization may have induced photon mass at that time.

    The second is a speculation on how a photon mass may affect a particular brane model and seems to imply that this would be well outside our current Hubble horizon anyway.

    If I'm wrong, please enlighten. Photons in our current universe are massless entities.
    Huh?
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  71. #70  
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    I freely admit that the discussions in these papers are too advanced for me to skim them and make the determination if they actually addrsss photon mass, physically, or only in bstract n-dimensional theory. I am a chemist, not a physicist.

    However, as a chemist I am familiar with the Compton effect wherein a photon transfers part of its momentum to an electron, reducing its total energy and thus shifting to a longer wavelength. As I recall from the minimal physics I did take, momentum is the product of mass and velocity so one can't have momentum without mass...

    Am I being overly simplistic? If so, please advise as to how a photon can have momentum but no mass?
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  72. #71  
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    Steve,

    Here's a good one:

    http://math.ucr.edu/home/baez/physic...ight_mass.html

    and,

    http://van.hep.uiuc.edu/van/qa/secti.../950669105.htm

    and,

    http://scienceworld.wolfram.com/physics/Photon.html

    This is what I meant when I said in an earlier post:

    "Photons have no rest mass (i.e. no mass) which is the only mass we're talking about."
    Huh?
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  73. #72 Ah 
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    Ah, I think that I am seeing the issue more clearly now. In the strictest of terms, that is rest mass, I can agree that at least there is no apparent mass to photons, yet. I do have some trouble with stating categorically that photons do not have mass but do have momentum, however...I suppose I am polluted by Newtonian physics.

    But when one observes phenomena like black holes sucking up light, one has trouble with light being massless -- at least this one has this trouble -- but if a photon has relativistic mass, I have no trouble any longer. I work with high energy lasers and am intimately familiar with the pressures exerted by coherent light at high fluence. Fortunately (or sometimes unfortunately), I am even more intimately expreienced with laser tissue interactions...not really, really high energy density, but my most powerful CW system has tagged me at ~5GW/cm^2 and that is high enough for my tastes. (Actually, the raw semi-collimated output does much more long term damage, but that is another story for another time.)

    I suppose my issue is with the distinction between relativistic mass and rest mass -- I like all my mass to be treated equally...and I have a dream...a dream that one day little relativistic masses will be judged by gravitational effects and not by the speed of it's travels

    In the inflationary universe, all bets are off for my comprehension as it seems the conditions were in the realm of the fantastic at that time, form anyone's point of view.

    You seem extremely adept at deciphering these cosmological physics topics...have you any insights as to dark matter?
    Dr. Silica

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    Steve:

    ...have you any insights as to dark matter?
    The latest one I like is the Higgs field and its accociated particles. SA had a good article recently that proposed that dark matter may be an, as yet undetected, supersymmetric partner particle(s) that arise due to certain interactions of Higgs fields. This stuff is predicted as part of the Standard Model and Supersymmetric Standard Models of particle physics.

    Discovery of the Higgs boson would cinch this.
    Huh?
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  75. #74 Re: Ah 
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    Quote Originally Posted by Steve Griffin
    I do have some trouble with stating categorically that photons do not have mass but do have momentum, however...I suppose I am polluted by Newtonian physics.
    Set E = mc<sup>2</sup>= hf and
    p = mc, then
    p = E/c = hf/c

    But when one observes phenomena like black holes sucking up light, one has trouble with light being massless
    If you allow yourself to think of the gravitational field distorting space-time, then anything travelling through space time, mass or no, will be affected equally. Which is also, incidentally, why objects of different mass appear to "fall" at the same rate.
    but if a photon has relativistic mass, ..... I suppose my issue is with the distinction between relativistic mass and rest mass -- I like all my mass to be treated equally
    Actually, nobody uses that term any longer, they simply call it "energy".

    If you were taught physics in the way I was, the confusion is understandable. At elementary level I was told light has effective mass p/c, meaning the interaction of light with matter had an effect equal to mass = m. Then I was told, later, no, no, it's relativistic mass through E = mc<sup>2</sup>, then finally to be told there's no such thing as relativistic mass. Confusing.
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  76. #75  
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    Higgs bosons...thanks, that helps Physicists have been looking for those for quite some time now...elusive little buggers. Bigger and better detector schemes had been proposed when I kind of drifted away from that area of instrumentation (could not get LLNL to guarantee payment in a timely enough manner to actually pay for the raw materials before getting sued, so I bowed out after prototyping a dozen segments of several thousand proposed; never found out if any were actually built).

    I'll track the SA article down, given time. Thanks
    Dr. Silica

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  77. #76  
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    Steve,

    The earliest indication I've seen is now 2007 before anyone achieves collision energies that could conclusively yield a Higgs.

    PS: Did you work at Livermore? Designing accelerator segments? Pretty cool!
    Huh?
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  78. #77  
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    One need not understand particle physics to develop detectors, and while I have worked with acellerators (in generating isotopes of Rf for study), I did not at LLNL.

    In fact, what I was told was that the detector segments that I was building were for a large array detector for bosons...the lead investigator referred to them as Pi bosons, but what he meant precisely by that I do not know since I only know of Gauge and Higgs...

    Anyhow, the detector was to be built of several thousand segments like the prototypes that I made. The prototypes were synthetic fused silica boxes, 10cm X 10cm by 1cm, with silica egg crates inside to shore them up when a high vacuum was pulled on them. There was a short stem tube in one corner to pull the vacuum through and to then fill and seal with a perfluorocarbon liquid (3M Fluorinert FC-75). As a boson passed through the liquid it was to generate gamma rays of characteristic energy...it was 15 years ago so I may have muddled the memory abit by too much tequila...

    The problem was that the plate stock (Heraeus Suprasil) used to build the boxes cost about $250 per box. We used a CO2 laser to cut the egg crates and weld the seams and had to anneal after each 10cm seam weld or the stresses would cause fracture during the next weld, i.e. they cost a great deal of money and time to make and I only had net 30 day terms with my silica plate supplier but Uncle Sam would not agree to pay for them until they were all finished...which meant I had to pony-up ~$2M for the couple of years it'd take to make them all. I passed -- told them to take the next higher bid (Japanese).

    I did some other interesting work on a liquid metal wire detector for ion beam positioning...
    Dr. Silica

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  79. #78  
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    Sounds pretty interesting Steve.
    Huh?
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  80. #79  
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    It can be...but in essence I am nothing but a scientific glassblower who uses lasers instead of flames with most of my work being done on the millimeter to micrometer scale. (The silica boxes were, by far, the largest things I'd ever fabricated in silica.)

    The acellerator related work was in grad school but even that was really work on the chemistry end that happened to require an acellerator to make the element of interest. My interest was in the heats of solution for Rf in fused salt eutectics for indication of whether or not it was "eka-Hafnium or something else -- that is Rf, as then modeled, had some inner shell electrons whose calculated "orbits" were too tight to exist unless the electrons were "orbiting" at speeds faster than light, so something had to be different than predicted.

    I built the detector -- high speed, high temperature inorganic gas chromatograph -- got the radiation training and was all set to go but never got enough funding to pay for the production run -- bombarding an Am target with a Ce ion beam.
    Dr. Silica

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  81. #80  
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    Steve,

    Was this part of your thesis work? Did you get to complete it?
    Huh?
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  82. #81  
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    Yes, it was a part of the thesis and not, I could not complete that one. I had to move on to Materials Science.
    Dr. Silica

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