Talk:Antimatter/Archive 2

Antimatter in fiction

This section is truly awful. I really think that we should apply the Wikipedia notability criteria to the entries there. As the template says, lists should not be just a collection of miscellaneous items. I propose that we require entries to have a reference to a WP:RS which cites their notability in connection with antimatter.

For instance, the first mention of antimatter in SF, the first use on TV or movies or a work that has played a part in bringing antimatter to the attention of the general public would all be notable. On the other hand, The Man from U.N.C.L.E. might be notable as a TV series (it had a cult following) but its use of antimatter as a plot device is devastatingly non-notable.

As far as I can see, all the current entries do not meet this criteria, at any rate there are no references other than self-refs. The only one that could conceivably be relevant was Asimov's positronics which he came up with shortly after the discovery of the positron, but this has already been deleted as irrelevant.

Any comments before I wipe it? SpinningSpark 17:06, 22 September 2008 (UTC)

I don't have any objections to wiping the whole "Antimatter in fiction" section. I did some repairs on it, but I agree it is pretty much a random collection and doesn't add much value to the article. However, I don't think it will stay wiped - there will always be editors who want the page to mention that their favourite sci-fi TV series has an anti-matter plot device. Maybe this needs a separate spin-off article, like List of fiction containing teleportation or List of references to cold fusion in popular culture. You could perhaps consult the folks at Wikipedia:WikiProject Science Fiction on how best to handle this - I see they have put their tag above. Gandalf61 (talk) 08:31, 23 September 2008 (UTC)

One thing I have seen done on other pages is to put in some hidden text reminding editors of the requirement for inclusion in the list. Of course, as you say, this will still not stop it, but removal then becomes a mere mechanical operation on the grounds of "against consensus", no emotional investment required. Not noticed the Science Fiction template before, bit of a stretch for them to include it in their scope IMO but I will take up your suggestion and drop them a note. SpinningSpark 18:24, 23 September 2008 (UTC)

I liked the section "Antimatter in fiction", epecially the part about Stanislav Lem, and I want to recover it. Most of people know about antimatter, lasers and black holes from fiction. They may look for explanations, we should send them to the correct place. How about to move the contert to Antimatter in fiction? dima (talk) 04:01, 4 October 2008 (UTC)

You look like an experienced editor, I'm sure you know how to extract the material from the history. If you are going to use the material as-is (rather than a coherent article), I would suggest a title like List of fiction with references to antimatter since it is largely a list of otherwise unconnected items. SpinningSpark 10:00, 4 October 2008 (UTC)

I think we need to have some mention of Star Trek, given that it's perhaps the most notable science fiction TV show ever, and the fact that antimatter is central to the functionality of nearly all of its fictional science. 71.203.209.0 (talk) 22:09, 3 December 2008 (UTC)

I know it played a major roll in a book called Angels & Demons. I don't know if you wish to add that or not. I was going to until I saw that it told me to take it to the talk page so I'll let you guys & gals decide if I should add it or not. Money2themax (talk) 08:23, 24 January 2009 (UTC)

Yes, Star Trek is notable, yes, Angels & Demons is notable, and yes, they both feature antimatter in the plot. It is certainly appropriate to mention antimatter in those articles. What is not appropriate is to list every occurence of antimatter in fiction in the antimatter article. That would be as silly as listing every occurence of "car" in the car article. Only works of fiction that are of special significance to antimatter should be mentioned, and only when there is a source saying it is of special significance to antimatter in fiction. Otherwise you just end up with unmanageable listcruft. As a point of information, Dan Brown's book has been deleted from that section multiple times already, and not always by me. SpinningSpark 12:50, 24 January 2009 (UTC)

Ok well I figured I would mention it and at least see what you would say. Money2themax (talk) 10:18, 1 February 2009 (UTC) Money2themax (talk) 10:20, 1 February 2009 (UTC)

Jack Williamson's first Seetee story in 1942, "Collision Orbit," was not the first science fiction story to feature antimatter. The earliest story I have found is "Minus Planet" by John D. Clark. [1] and [2] are two sources. Nevertheless, because Williamson published a long series of antimatter stories in the most prominent SF magazine, his work brought attention to antimatter in a way that previous stories had not, and may still be worthy of mention in this article. See further disussion here: [3]Beamjockey (talk) 00:24, 24 March 2009 (UTC)

I agree, those are good references. Your first ref seems to also be saying that there was an even earlier story by Frank Long and that Arthur C was the first to propose antimatter as a propulsion system. SpinningSpark 10:26, 25 March 2009 (UTC)

I see talk but no action. This section is still very out of place and does not really enhance the article in anyway. Someone can write a better one in later if they wish but I am wiping it as I have been encouraged to be more bold in my edits. If you don't like it you can undo the wipe and I won't argue. Skeletor 0 (talk) 15:51, 9 April 2009 (UTC)

Mass?

I recently heard that antiparticles have a negative mass, so that when a particle-antiparticle pair forms on the event horizon of a black hole, and the antiparticle falls in, it adds a negative mass to the black hole. Also, E=MC^2 supposedly should be changed to E=+_MC^2 (positive/negative mass) in order to derive antiparticles. Additionally, if antiparticles are normal particles travelling back in time, then the have a negative speed to an outside referencer (which in the equation may be converted to negative mass). However, everything else says that the antiparticle has the same (not opposite) mass of its particle partner. Also, how does the black hole "know" which particle is falling into it, and therefore "decide" to grow or shrink appropriately? Last, I have also heard that the particle that escapes, gets a "kick" from the blackhole, stealing some energy. Are these just different paradigms? Also, the partners are antiparticles to eachother but not to themselves, so does that mean in their own frame-of-reference, they have a positive mass and the other has a negative; just as someone cannot travel back in time in their own frame of reference? Thanks 98.27.163.42 (talk) 01:04, 10 October 2008 (UTC)

Mass is positive for both particles and antiparticles, never negative. Before anything along those lines could be put in the article, you would need to cite a reliable source; "I recently heard . . " cannot be checked up by other editors. For your other questions, I highly recommend the science section of the Reference Desk where the volunteers there will be delighted to answer all knowledge questions. This page should only be used for discussing improvements to the article. SpinningSpark 08:38, 10 October 2008 (UTC)

calculation given for the amount of antimatter created by CERN per year

The calculations given for the amount of money it would take to create 1 gram of antimatter given CERN's annual production of "several picograms" is off.

If I assume "several picograms" is seven trillionths of a gram, and this costs $20 million, then the calculation (20 * 10^6) / (7) * (10 ^ 12) = 2.86 * 10^18, which is much more than the figure of 100 quadrillion dollars given.

I have no idea what the correct numbers are, however, I can't reconcile the two numbers given in the article.

Please fix. —Preceding unsigned comment added by 98.14.225.194 (talk) 03:25, 26 October 2008 (UTC)

These are pie in the sky calculations and should not be taken too seriously. Also, it is a quote (but unfortunately not referenced) of what someone has said. It may be wrong, but if that's what they said, then that's what they said. The numbers: you are not entitled to re-interpret several picograms as meaning seven. It is vague and could mean anything from "one and a bit" to a thousand. Looking on the CERN Q&A (ref 10) they say one nanogram in ten years. That's 100 picograms in one year. A gram will thus require 10¹⁰ years. The 10 year cost is stated as "a few hundred million swiss francs". That's few x 10⁸ SF. Multiplying by the number of ten year periods required gets a few x 10¹⁷ SF. One hundred quadrillion is 10¹⁷ (short scale) if I am not mistaken, which puts it in the right ballpark. I don't think the change from swiss francs to dollars is going to be significant on such a vague calculation, but the current rate is 1SF = 86 cents US. You would need to evaluate 0.86few to actually make the conversion. SpinningSpark 14:21, 26 October 2008 (UTC)

At Fermilab (where I work) the rate has steadily improved; as of June 2008, according to this article [4] the rate in 2007 was about 20x10¹⁰ antiprotons per hour and in 2008 is 25x10¹⁰ per hour. This is about 0.4 picograms per hour or 10 picograms per day. Fermilab does not run every day of the year, but in 2008 we have probably exceeded 2 nanograms and possibly exceeded 3. I find $10¹⁷ per gram to be a reasonable guess for the cost of antiprotons, approximately consistent with the CERN estimate.

Beamjockey (talk) 22:39, 31 October 2008 (UTC)

I am just wondering about the discrepancy in the article about the cost of Antimatter. In the Artificial Production section Sub Section Cost it is referenced that it would cost $62.5 trillion per gram. Whereas in the Uses section Sub Section Fuel it is mentioned it would cost 100 quadrillion dollars to produce a gram. Obviously these figures are completely different and would confuse anyone trying to research the area.

I believe these two figures should be clarified further to lessen the confusion people may have reading this article. As I understand the CERN figure comes from actual production of Antimatter; where does NASA obtain their estimates from?

Also maybe place the CERN figure inside the Cost section as they are related.202.81.18.30 (talk) 02:34, 2 June 2009 (UTC)

New Breakthrough in Production

In an acticle on Nov 17, it states thats they have discovered a new method of creating antimatter in a laser experiment on the order of billions of particles of positrons, Billions of particles of anti-matter created in laboratory, this is the most antimatter produced with the least amount of energy input.--Crab182 (talk) 15:45, 18 November 2008 (UTC)

That's interesting stuff, they used gold but perhaps other high-Z elements like tungsten would work? Is there any discussion on the theoretical basis for this experiment? Aksel89 (talk) 11:43, 21 November 2008 (UTC)

I wouldn't suggest changing the main page based on that - similar to WP:MEDRS, news reports generally don't describe science well (though a physics-dedicated news source might), and until this has been replicated and confirmed (and reported in a peer-reviewed journal) I would consider it undue weight to put a lot of emphasis on it. WLU (t) (c) ^{(rules - simple rules)} 11:53, 21 November 2008 (UTC)

Discovery?

Who "discovered" antimatter and how? Is this real or one of those theories that scientists tell us is just as good as fact? After looking into modern scientific theory I've lost faith in the Scientific Community. This article needs specific info on how antimatter was discovered, and how it was proven to be actual. This is just a list of "facts" and features of antimatter with no real context to show how these conclusions were reached or observed. 69.3.84.236 (talk) 19:04, 5 January 2009 (UTC)

The positron article has a fairly good discussion about antimatter discovery. may be a link would suffice? To the point of your question: The existence of antimatter was first proposed by Dirac in 1928. It is believed that its first observation happened in 1930, but that was not realized at the time. The official discovery date was 1932. I hope that helped. PS don't lose faith in science. Dauto (talk) 22:54, 5 January 2009 (UTC)

Antimatter is very real. Positrons (anti-electrons) were first observed in cosmic rays 1932, antiprotons were first created artifically by colliding beams of protons in 1955, and antihydrogen atoms were first created artifically in 1995. It even has a few practical applications, such as positron emission tomography. But other possible applications such as antimatter rockets and antimatter weapons are likely to remain theoretical for the forseeable future, because they require much larger amounts of antimatter than can conceivably be produced or collected. There is an interesting quote towards the end of the article that says that all of the energy in all of the antimatter ever produced at CERN is only enough to light a light bulb for a few minutes. Gandalf61 (talk) 09:59, 6 January 2009 (UTC)

Antimatter as fuel

This bit here seems a little suspect: "In fact, the energy in a few grams of antimatter is enough to transport an unmanned spacecraft to Mars in a few minutes." Doesn't *light* take a few minutes to get to Mars? I had heard of ideas for a manned antimatter-powered ship that would take about 3 days to get to Mars; although I don't have a source for that. Kyle90 (talk) 19:25, 22 January 2009 (UTC)

Yes, very suspect. That whole paragraph was unsourced, so I have re-written and shortened it. Gandalf61 (talk) 09:35, 23 January 2009 (UTC)

Antimatter Production Versus Antimatter Collection/Refining

Most people would not state that Gold, or other valuable commodities are Produced. Rather, they are refined or concentrated or collected from pre-existing starting materials. The article by Bickford "EXTRACTION OF ANTIPARTICLES CONCENTRATED IN PLANETARY MAGNETIC FIELDS", which looks promising (though is far from containing ideas which I would say have been verified) indicates a scheme of antimatter concentration.

ConcernedScientist (talk) 00:55, 18 February 2009 (UTC)

Can you explain then, why "gold production" gets 537,000 ghits but "gold extraction" only gets 39,900? Of your other terms only "gold collection" gets significantly more hits but most are for a different meaning of the term, as in jewellery collection. SpinningSpark 13:40, 12 March 2009 (UTC)

"Ante matter"

Ante matter was just created as a redirect to this page. Is this really a "common misspelling or misnomer" for antimatter? Otherwise CSD R3 applies. decltype (talk) 12:38, 12 March 2009 (UTC)

I very much doubt it is a common mispelling. But in fact the article was turned into a redirect to get rid of this: Matter from other realities. Also called Exotic Particles, Z Matter, which is nonsense and the redirect is an improvement, but it does indicate that the author thinks that it is something different from antimatter. The origianl should have been AfD'd, but the conversion to a redirect is a good excuse to speedy it. In either case I agree it should be deleted. SpinningSpark 13:26, 12 March 2009 (UTC)

Yep, I was about to speedy it as nonsense, but then I noticed that exotic particles actually "exist", and in the meantime, another editor made a redir. decltype (talk) 13:55, 12 March 2009 (UTC)

Yes, exotic particles do exist, and so does the Z boson and who knows what exists in alternate realities, but none of them are (or need to be) anti-matter. SpinningSpark 14:02, 12 March 2009 (UTC)

On second thoughts, having now done a google search and got a surprising number of hits, perhaps the redirect should stay, even though a lot of those hits are from game playing sites which seem to have a concept of "ante matter" rather similar to the original article. SpinningSpark 13:57, 12 March 2009 (UTC)

Just wondering

I may be mistaken but it is my understanding that matter antimatter reactions are the only reactions that are exempt from entropy (in other words they are 100% efficient). I was wondering if this should be put in the article as it is a very interesting characteristic that has an effect on many of the applications of antimatter. Skeletor 0 (talk) 15:41, 9 April 2009 (UTC)

The statement "matter antimatter reactions are the only reactions that are exempt from entropy" doesn't strike me as being very meaninfull. If you mean that those reactions somehow avoid the second law of thermodynamics, that is incorrect. Dauto (talk) 06:03, 10 April 2009 (UTC)

But they do (I think...) They produce pure energy with no waste products whatsoever. No matter or antimatter is left (assuming there was equal amount of both to start with. Thus you get 100% of equivalent energy of those masses as described by E=Mc2. Right? Skeletor 0 (talk) 18:00, 14 May 2009 (UTC)

Mistakes... and difficulties correcting them :(

According to this article, Tsar Bomba required the use of hundreds of kilograms of fissile material. This is nonsense - Tsar Bomba was a fusion weapon and as such, did not contain hundreds of kilograms of fissile material. The energy was from fusion, not from fission.

Later in the article, this brilliant conclusion: "But cold antihydrogen is far more difficult to produce than antiprotons, and so far not a single antihydrogen atom has been trapped in a magnetic field." Another nonsense, since you obviously can't trap a neutral atom in a magnetic field.

But worst of all, it's very difficult to actually remove such crap from wikipedia articles. If I try to delete it, it gets automatically restored. If i write a comment in the article, it gets deleted (the comment, not the nonsense). If I write a comment in the discussion, nothing happens. It took me several days to remove an obvious fraud from the radiation poisoning article (a story about natural radium mine...), now I don't even want to try again...

fusion weapon contains a fission bomb as a primary stage or "trigger", and may also contains fissile material within the secondary stage. The "hundreds of kilograms" may be an exaggeration, though. Gandalf61 (talk) 14:35, 24 June 2009 (UTC)

Technically, yes. However, the article says "Tsar Bomba... reacted an estimated yield of 50 megatons, which required the use of hundreds of kilograms of fissile material (Uranium/Plutonium)." For someone who is not already competent in the subject (it's the target audience of the encyclopedia, yes?), this phrase means that "hundrers of kilograms of fissile material" generated the yield of 50 megatons. Which is wrong.