Talk:Zero-point energy
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[edit] Conservation of energy
If the universe is expanding as commonly believed, and vacuum has energy, then the first law of thermodynamics is violated. —Preceding unsigned comment added by 90.242.67.71 (talk) 12:55, 6 February 2008 (UTC)
Assuming its a constant, or assuming that there is energy. Here it states that it is the lowest possible energy. Which could be zero. Not laws would be broken. Crakker (talk) 02:57, 26 February 2008 (UTC)
If you want to consider conservation of energy being violated, you need to consider everything - not just the thing that's gaining energy. Anyway, this is a comment to make in a physics classroom, not the discussion board. 151.151.73.165 (talk) 17:33, 20 May 2008 (UTC)
[edit] I thought Zero-point energy is an alleged source of "free" energy?
The intro of the current version of this article doesn't seem to be saying much of anything. It is my understanding that Zero-point energy is actually an alleged source of "free" energy, I think the intro and/or article should specifically state that people are researching/theorizing using or tapping zero-point energy for energy production [1] [2] zen master T 20:45, 29 December 2005 (UTC)
- Note: I just gave the article a lot of simple-to-read intro, I don't know if it addresses the problems discussed here because I don't have time to read them or read the rest of the article. Therefore, I leave the discussion as is, below. -- Efilnickufesin 07:05, 3 January 2006 (UTC)
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- Dear Efilnickufesin, if you "don't have time to read them or read the rest of the article", please don't edit the article. Besides that, there are several problems with the things you wrote: (1) In the Casimir effect, the force between the plates is attractive, not repulsive; (2) In the Casimir effect, the plates are brought close to each other since then the force is bigger (see formula), and not because air molecules cannot fit between the plates; (3) There is a separate article on the Casimir effect, so we shouldn't describe it again here; (4) You don't need the Casimir effect to provide an example for the zero-point energy - even the hydrogen atom is good enough; (5) It is an inaccurate statement that particles appear out of nothing in the vacuum. Vacuum is an eigenstate of the Hamiltonian, therefore nothing changes there; (6) It's not the place to discuss 'fights' between classical and quantum mechanics. An article on quantum mechanics or articles linked from there are the appropriate place. For these reasons, I undid your changes. If you still think that some of them should be included, let's discuss them here first. Yevgeny Kats 07:53, 3 January 2006 (UTC)
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- "At a cavity-resonance frequency the radiation pressure inside the cavity is stronger than outside and the mirrors are therefore pushed apart. Out of resonance, in contrast, the radiation pressure inside the cavity is smaller than outside and the mirrors are drawn towards each other." [3]
- Re vacuum == nothing, yes, hamiltonian says it isn't nothing, but most people see the world through perceptual organs that perceive aggregate, classical-type phenomena, and believe vacuum == nothing. That is why it needs explaining in the first part or two, and why it is darned appropriate to explain the difference between classical and quantum physics also, in the brief human-readable intro.
- If you ignore my suggestion, and put a bunch of what others have termed 'gobbeledegook' first, in order to be scientist-like and impress your learned colleagues, then most readers, who come here to learn something they don't already know, will continue to describe it as gobbledegook and see the technically literati as a bunch of white-tower mystics engaging in so-much hand-waving. Their appropriate reaction would be to engage in the same behaviour, and produce more and more of these 'zero point energy' devices and other mystical toys that they don't understand, and won't have explained to them - since they can see, and rightly so, that your arguments consist mostly of ego, with a bit of hocus-pokus thrown in, and stop reading before you get to the actual point.
- The fact is that if you do not present a simple example, that is "intuitively" understandable, at the start, people won't read the page. If you put such an example later on, they won't read the page. The intuitive example will be missed.
- I think it was inappropriate of you to reverse the change. You should have fixed any small errors I introduced ...
- Because it is an example which uses human-scale objects, and produces completely counter-intuitive results, the Casimir effect is a much better example than some hydrogen-atom thingo -- which you didn't even bother to describe or replace my example with -- and because of the counter-intuitive results and the fact that zero point energy is a qm phenomenon, of course it is necessary for a non-qm-educated person to be informed that there is a difference between qm phenomena and intuitive/classical descriptions of the world, and briefly have summarised for them what that difference is and what type of difference it is, and the relative newness of qm.
- You need to learn that communication, and especially wiki, is about cooperation between disparate people, with differing skills and knowledge. So you believe you know more physics than me. But you can't write for shit if you reversed my changes. You need to learn to accept useful input, and improve it. I didn't scratch the entire page, I added my contribution, adapting a small part and fleshing it out. You shouldn't have removed my entire contribution, you should have adapted a small part and refined it or corrected it.
- Note I wrote most of this before I confirmed that I was in fact not completely wrong about the Casimir force, and so I have perhaps been more polite than I should in responding. But since I don't have time to completely satisfy myself of the correctness of my argument or the incorrectness of Yevgeny's, I will leave my reply somewhat ambiguous. Someone needs to check carefully whether the Casimir effect is accurately described, and whether there is a better candidate for an example. Please take into account that the example should be understandable and "of consequence" to people who are not yet educated in subatomic physics.
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- To repeat myself, for the benefit of those trying to follow the flow of this discussion (could anyone do some work to tidy up this page?): Note: I just gave the article a lot of simple-to-read intro, I don't know if it addresses the problems discussed here because I don't have time to read them or read the rest of the article. Therefore, I leave the discussion as is, below. -- Efilnickufesin 07:05, 3 January 2006 (UTC)
- Yes, it is. This article needs to be torn down and re-written from scratch. It needs to describe zero-point energy as taught in undergrad physics, zero-point energy as conceived by particle physicists and cosmologists, zero-point energy as conceived by the over-unity and free energy crowd, and finally the other miscellaneous cultural references. Quite possibly, this should be split into two or three distinct articles, so that we don't have the scientists warring with the pseudoscientists over the topic. Right now, its a hopeless mish-mash of all of these topics, and is, as you point out, throughly uninformative. linas 21:15, 29 December 2005 (UTC)
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- Perhaps this article was intentionally made as an ambiguous mish-mash to ease the portrayal of something like free energy as "pseudoscience"? I agree we need disambiguation and disassociation here but I am wary of your "pseudoscience" comment. zen master T 21:42, 29 December 2005 (UTC)
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- Oops, I meant Free energy suppression. linas 02:05, 30 December 2005 (UTC)
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- Where is the article that describes just the zero-point energy hypotheses for "free energy" outside the dismissive "conspiracy theory" label? If an article only contains hypotheses surrounding the details of zero-point energy directly, and leaves out speculation as to someone's possible motivation for supressing that technology then it can't possibly be labeled a conspiracy theory. Critics of the "conspiracy theory" label claim it is used, often subtly, to pejoratively confuse and misclassify an actual theory that alleges a conspiracy with the type of eccentric folklore for the purpose of obfuscation and to thwart a scientific and factual analysis. The label may even be considered inappropriate if used to dismiss theoretical speculation in any form. I think the same case could be made for "pseudo-science" as it is seemingly also used to discourage a scientific and factual analysis. zen master T 02:28, 30 December 2005 (UTC)
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- You are quite right. This article needs to be torn down and re-written from scratch. It needs to describe zero-point energy as taught in undergrad physics, zero-point energy as conceived by particle physicists and cosmologists, zero-point energy as conceived by the over-unity and free energy crowd, and finally the other miscellaneous cultural references. Quite possibly, this should be split into two or three distinct articles, so that we don't have the scientists warring with the pseudoscientists over the topic. Right now, its a hopeless mish-mash of all of these topics, and is, as you point out, throughly uninformative. linas 06:23, 30 December 2005 (UTC)
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- Who is alleging something or someone is pseudoscience or a pseudoscientist here and what exactly is this alleger's criticism? zen master T 06:48, 30 December 2005 (UTC)
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I am alleging that the topics of zero-point energy and "free" energy attract a lot of cranks and kooks; this is fairly common knowledge, and if you google around, you will see that this is true. This article should describe not only the legitimate meanings of these terms, but it should also describe the the crank community and its researches and findings. linas 06:39, 31 December 2005 (UTC)
- I am afraid wikipedia policies require us to state who believes the "free energy" aspect of zero-point energy is "crank". It is inappropriate to label theoretical speculation as "pseudoscience" as that will thwart and discourage a scientific analysis. The "free energy" aspect of zero-point energy isn't even mentioned directly in this article ("cultural references" doesn't count), labeling something as fiction is a great way to dismiss and obfuscate. zen master T 06:56, 31 December 2005 (UTC)
- "I am afraid wikipedia policies require us to state who believes the "free energy" aspect of zero-point energy is "crank". " - Not when it's the majority of mainstream science that considers it as such. Take Intelligent design, a large number of its supporters are very successful acredited high profile scientists, but the mainstream scientific community consider it Pseudoscience, thus it is labeled as such. What seperates ZPE from a protoscience like String Theory is that the majority of ZPE supporters and reserarchers dont use the scientific method and even believe in its practical application for free energy and have patented thousands of machines for it over the years... You dont see such similar patterns in the majority of string theory String Theory. You can determine easily when something is psuedoscience when the majority of supporters make claims that have no grounds in science yet pretend to be, thats why established fields like chiropractic care and Reflexology are psuedoscience because the claims put forth have no grounds in science, and yet claim to be scientific. - UnlimitedAccess 18:35, 2 January 2006 (UTC)
- If theoretical speculation follows sound scientific practices, then it is scientific discourse. If it contains numerous flawed or mistaken arguments, ie is based on incorrect factual assumptions, then call it what you like, but don't call it science. Same if it uses unsound maths. Science and maths, contrary to popular belief, are not magic, and not religion. That many superstitious pricks dress up their religiously-maintained self-delusions as science is not science's fault. Scientific method is a simple and commonsense technique, of think, test, (refine, retest ad infinitum) ... present results for critique, analysis, and use. Maths is similarly derived from commonsense, real-life observations, using logic, and if not provable by robotic, mechanical deductions, deemed to be unsound and bogus and offensive to humanity. Please refine the article (and the discussion of the article) according to these linguistic criteria, which might be said to be fact, were it not for the case that so many speakers of the words science and maths speak them vacuously or with mal intent. -- Efilnickufesin 06:27, 3 January 2006 (UTC)
- To say that "Science and maths, contrary to popular belief, are not magic, and not religion" may not be quite so true as they were once perceived. If one reads "The Field" by Lynn McTaggart as an introduction to zero point energy and related physics, biology, physiology and medical topics, then much of what is described about the action of the brain as a mechanism for interacting with The Field (aka zero-point energy) seems to go some way towards explaining aspects of religion and aspects of magic.
- I offer one example for each in support of this proposal.
- Some religions acknowledge a god, some acknowledge multiple gods, some point to a being of vastly greater intelligence / presence (e.g. Gaia), astronomers refer to the mising mass, Einstein talked about E=mc². All of these have a common factors - not visible to the eye, significant energy, vast size, not easy to understand. The prevalence of religion among human cultures, together with the associated links to spirit, points to thought as a causal and linking factor. With the brain acting as a complex store cum energy manipulation device, it is in effect acting as a transducer, sensing (receiving) and interacting with (sending) the zero-point energy field. (my regrets if the simplification has glossed over or missed out much of the underlying logic).
- For Magic, the matter is both simpler yet more complex. If we take the Magic (paranormal) definition of Magic from Wikipedia itself, the first entry in the Examples box is about Healing Others. Elisabeth Targ and Fred Sicher showed in their 1988 study of distant healing that some effect of human activity on others - by thought alone - had produced a statistically significant effect. If we accept that the human brain is an (unreliable) transducer to link with the zero-point energy field, this would go a long way towards explaining a) why the experiment succeeded and b) why zero-point energy manipulation is "Magic".1stonery 03:26, 2 February 2007 (UTC)
- If theoretical speculation follows sound scientific practices, then it is scientific discourse. If it contains numerous flawed or mistaken arguments, ie is based on incorrect factual assumptions, then call it what you like, but don't call it science. Same if it uses unsound maths. Science and maths, contrary to popular belief, are not magic, and not religion. That many superstitious pricks dress up their religiously-maintained self-delusions as science is not science's fault. Scientific method is a simple and commonsense technique, of think, test, (refine, retest ad infinitum) ... present results for critique, analysis, and use. Maths is similarly derived from commonsense, real-life observations, using logic, and if not provable by robotic, mechanical deductions, deemed to be unsound and bogus and offensive to humanity. Please refine the article (and the discussion of the article) according to these linguistic criteria, which might be said to be fact, were it not for the case that so many speakers of the words science and maths speak them vacuously or with mal intent. -- Efilnickufesin 06:27, 3 January 2006 (UTC)
- "I am afraid wikipedia policies require us to state who believes the "free energy" aspect of zero-point energy is "crank". " - Not when it's the majority of mainstream science that considers it as such. Take Intelligent design, a large number of its supporters are very successful acredited high profile scientists, but the mainstream scientific community consider it Pseudoscience, thus it is labeled as such. What seperates ZPE from a protoscience like String Theory is that the majority of ZPE supporters and reserarchers dont use the scientific method and even believe in its practical application for free energy and have patented thousands of machines for it over the years... You dont see such similar patterns in the majority of string theory String Theory. You can determine easily when something is psuedoscience when the majority of supporters make claims that have no grounds in science yet pretend to be, thats why established fields like chiropractic care and Reflexology are psuedoscience because the claims put forth have no grounds in science, and yet claim to be scientific. - UnlimitedAccess 18:35, 2 January 2006 (UTC)
I don't have the knowledge to even attempt to edit this article but I do think it's pretty dismissive of the idea of using Zero Point for energy, as some people have already said. I agree that it's wrong to label this pseudoscience. For example, ZPE does not as far as I'm aware violate any laws if it gets the energy from other dimensions which I believe many physicists speculate exist. There appear to be a number of unexplained over-unity phenomena out there (e.g. "cold fusion" and ZPE may well be the underlying cause. Rhm01 13:27, 7 March 2007 (UTC)
[edit] for dummies?
I have to say I'm with Linas on this one. A "for dummies" section is not very encyclopedic. Having separate headings for each why/what/etc. is not encyclopedic, and a lot of the actual writing is questionable (in particular the Casimir effect is most cerainly not due to "spontaneously forming partical/energy fields resonating between the plates.") All of the stuff in there can be probably rewritten as a one-to-two paragraph part of the introduction. I will try to get to it soon. ObsidianOrder 20:13, 6 January 2006 (UTC)
- Well, now someone has replaced the intro with some jargon again. This is why I clearly labelled it. Please find a solution if you didn't like mine, since the article is going to continually be reverted so that it starts off like a technical handbook, when a large number of non-technical users have expressed a need for something understandable.
- Perhaps put a link at the very top, to a separate article which is written for non-technical readers. Make a note next to the link, in the source, that the link is not to be moved from the top.
- Readers who encounter something they don't understand at the start of an article stop reading straight away -- they don't find a simple explanation unless it is at the start. Even if you put one single, short, accurate, succinct paragraph of technical gobbledegook at the start, then a simple lay-explanation the lay-readers won't read it because they don't know if they understand it correctly, since they didn't understand the first paragraph. This is what makes them non-technical readers -- they often don't have the ability to parse technical jargon for meaningful terms. It is not always just a lack of knowledge, often a lack of developed ability as well. -- Efilnickufesin 03:40, 12 January 2006 (UTC)
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- I re-wrote/re-organized the article; I am hoping that it is now more readable and more comprehensive. I managed to delete the Reuda-Heisch paragraphs, which I invite someone to put back, ideally in the form of one or two paragraphs that link off to a larger article on the topic. linas 07:35, 12 January 2006 (UTC)
- Well I'm no Sam Carter and in fact didn't understand most of the article, but the opening paragraph didn't deter me from continuing, so it's not that bad. [Haliski]
[edit] Ground state energy
Linas, according to your new definition, the zero-point energy is the energy of the ground state (or the lowest eigenvalue of the Hamiltonian). You know, however, that one can add a constant to the Hamiltonian (w/out gravity) and it still provides the same description of the behavior of the system. However, all the eigenvalues will be shifted by this constant. Therefore, your zero-point energy is defined up to an arbitrary constant. I'd rather say that what is meant by the term "zero-point energy" is the difference between the minimal quantum-mechanical energy and the minimal classical energy, as the old definition said. (On the other hand, the vacuum energy, which is relevant for cosmology, does include the constant term. The zero-point energy is then only one of the contributions to the vacuum energy, the purely quantum-mechanical contribution.) Yevgeny Kats 11:08, 12 January 2006 (UTC)
- I believe you have that reversed: in classical physics, you may add a const to the classical hamiltonian without changing the resulting equations of motion. In quantum mechanics, you may do so also, by lumping the const in with the potential (so that K.E.=mv^2/2 is preserved). Note that for QM, this is less-than satisfying, since the constant gets pushed into the operator, which is not so beautiful; adding a const to all the matrix elts of an operator is not really right, although it can be sort-of excused. In QFT, the hand-waving is worse, because now you have to preserve E^2=p^2+m^2 so there's no where to lump the constant. In QFT, in a hand-waving way, the mass is the zero-point const; you can't adjust that. You can hand-wave it away because it doesn't affect e.g. one-loop and multi-loop mass corrections to propagators, but its "still there" in a deep sense. This is exactly why the string and M-theory guys take this all so very seriously: they really do equate the zero-point energy with the cosmo const, and desperately want to explain how it can be so small. linas 15:28, 12 January 2006 (UTC)
- This is particularly evident in solid-state physics, where the mean-square displacement of an atom in a crystalline lattice doesn't shrink to zero as temperature (number of phonons) goes to zero. I believe they've even made electron microscope pictures/measurements of this. linas 15:34, 12 January 2006 (UTC)
- I thought about this on the drive in to work. For the classical pair of orbiting electrical charges, the classical minimum energy is minus-infinity. So saying that the zero-point energy of the hydrogen atom is plus-infinity minus 13.7 is kind-of-weird if not outright wrong.
- Compare this to the zero-point energy of hydrogen derived from the uncertainty principle: the Bohr radius of hydrogen is R=0.53 angstroms. Thus, momentum uncertainty of electron = R/hbar. The average velocity of the electron in the hydrogen atom is momentum/electron mass = speed of light/137. Cool, huh? The non-relativistic energy of something moving at that speed is mv^2/2. Plugging in numbers, using 511 KeV for the electron mass, and 1/137 for the fine struct const, we get E = 511KeV / (2 (137)^2) = 13.6 eV. So the uncertainty principle applied to the atomic radius gives us exactly the ground state energy of hydrogen. Cool, huh? Its quite amazing that this jig-saw fits together in this way. linas 17:35, 12 January 2006 (UTC)
- typo. Should be momentum uncertainty of electron = hbar/R . Other than that, what you say is pretty groovy, but isn't it the case that the Bohr radius was DEFINED as that distance such that this calculation you're doing does come out exactly? The electron cloud is a fuzzy ball, so to give it a nominal radius, you pick Bohrradius = hbar 137 / mc. Or am I missing something? GangofOne 20:00, 12 January 2006 (UTC)
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- The Bohr radius isn't normally defined to make this relation come out; (although I suppose one could, if one really wanted to). I believe that the current "textbook definition" would be that it's the RMS radius of the ground-state solution to the Schroedinger equation for hydrogen. As Yevgeny points out below, the sign is wrong, and contemplating that can yield further interesting insight. linas 00:32, 14 January 2006 (UTC)
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- Linas, regarding your last paragraph above, where you calculate the energy of the hydrogen atom: it's a nice example, but for the article "ground state energy" rather than "zero-point energy". And your sign is wrong (positive instead of negative). The reason for the sign error is that you don't take the potential energy into account. Energy eigenvalues in quantum mechanics describe the sum of the kinetic and the potential energy, not just the kinetic energy.
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- Is the zero-point energy of the hydrogen atom "infinity minus 13.7", like you interpreted my approach? I would say yes. (There could be some cutoff in that classical theory though.)
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- Sorry, I didn't understand the claim at the beginning of the first paragraph of your response, but I won't argue, since it ends with the words "it can be sort-of excused" :). Then you're talking about E^2=p^2+m^2, but this is true only while the particle is not interacting. Description of interacting particles is described by a Hamiltonian involving fields, and you can add a constant to the Hamiltonian (and this wouldn't affect the equations of motion of the field). An example of a situation where a constant is naturally added to the Hamiltonian is a spontaneous symmetry breaking. This constant contributes to the vacuum energy together with the zero-point energy.
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- I agree with your solid-state example, but I don't understand how it is relevant to our controversy. Yevgeny Kats 21:07, 12 January 2006 (UTC)
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- I didn't realize it was much of a controversy. I did get nervous by the claim that the zero point energy is the differerence between the classical and quantum systems. It's not clear to me that this is the correct definition, but it certainly does raise interesting questions. If you insist, I suppose it can go into the article, but I'm not sure what purpose it serves. Certainly, I'm having trouble understanding how to compare the energy of classical and quantum systems, and I'd like to think of myself as a bit smarter than the average reader. I'm willing to compare the energy of classical and quantum harmonic oscillators, and also for SSB/Higgs-type mechanisms, since the interactions are quadratic. It's not clear that taking such a difference works for more complex systems; I find the "infinite" energy difference (or Planck-scale energy, if you wish) between the classical and quantum hydrogen/planetary system to be ... strange .. and thought provoking. linas 00:32, 14 January 2006 (UTC)
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[edit] Bell Labs show Casimir force on nano machine
http://www.trnmag.com/Stories/021401/Quantum_effect_moves_machine_021401.html
A very interesting article about the work Bell Labs has been doing to look into the potential problems of "Nano bots" due to zero-point energy.
[edit] Extracting energy
took out 2006 agreement about zero-point because i found no evidence to back it up, please produce some proof from a peer reviewed journal. (User:80.6.42.220 on 22 feb 2006)
- The above comment concerns the phrase:
- As of 2006, mainstream science does not believe that it is possible to extract usable energy from the vacuum.
- which appears in the introduction. I re-inserted this sentence, its deletion was absurd at best. linas 19:49, 26 February 2006 (UTC)
Why absurd? I have seen no proof for this statement other than this article. Please provide a link to a reputable source for this. If you cannot, i will continue to remove it.
- Don't do any such thing. Instead, cite a counterexample. I think it's quite fair to say that if pseudoscientists claim something about physics, and mainstream scientists don't write any papers about it, that it's because the mainstream scientists don't think it's possible. -- SCZenz 02:50, 12 March 2006 (UTC)
That is not necessarily true. Mainstream scientist know that it exists by the Casimir effect and it being measured in 1959. But I am happy with the improvement. It claims that we cannot harness the energy for usable purposes yet, rather than claiming that there is no energy there to be harnessed for practical uses. Thank you for the correction
- The 1984 paper by Robert Forward (Phys. Rev. B 30: 1700) explicitly states that you can in principle extract energy. This is straight from the references section of this article btw. I'm not sure why this is even an issue? Nobody is claiming that this is a practical possibility today. At the same time, nobody is claiming that it is not a theoretical possibility - are they? Can we get a counter-reference? ObsidianOrder 00:26, 14 March 2006 (UTC)
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- Can you articulate Forward's argument that energy extraction is possible? linas 01:01, 14 March 2006 (UTC)
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- Best look up the original article: [4]. Forward talks about a reversible ZPE battery charge-discharge cycle, but the battery starts in the charged state as initially constructed (and without any corresponding energy input during construction). The energy in the first discharge apparently comes straight from the vacuum. A more recent analysis (Cole & Puthoff, 1993, Phys. Rev. E 48, 1562–1565, [5]) confirms that conclusion. ObsidianOrder
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- I once read Forward's paper. I was wondering if *you* could articulate the argument. I agree that in principle, it is possible to build this "battery" and discharge it, and therefore suck energy out of it. However, this neglects the energy used to construct the thing in the first place. In particular, Forward's device is not a perpetual motion device. linas 02:25, 14 March 2006 (UTC)
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- "neglects the energy used to construct the thing in the first place" - Not true - as I said there is no relation between the energy that can be extracted and the energy needed to build it. What is the physical lower limit on the energy needed to build it, anyway? (I would suggest that can be arbitrarily close to zero, but that depends on your definition of "build" as well - let us say "bring the components together into the correct configuration"?). "not a perpetual motion device" - Obviously, since in any cycle of build-discharge-charge-unbuild energy will be exactly conserved. Nonetheless, it is a device which extracts usable energy from the vacuum, which was the whole point. You can argue that the components of the device are "fuel" which is consumed, but that would not be exactly correct: yes, they are consumed, but the energy does not come from them. ObsidianOrder 02:32, 15 March 2006 (UTC)
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- The intent of the phrase "does not believe that it is possible to extract usable energy from the vacuum" was to say "mainstream science does not believe it's possible to build perpetual motion machines based on ZPE". It was not the intent to exclude Forward's device, which, if I remember it correctly, struck me as a reasonable device. The problem is that the phrase "extract usable energy from the vacuum" sounds like "something for nothing"; Forward's device doesn't actually give you something for nothing (because there was a real energy cost to manufacture the thing). linas 02:35, 14 March 2006 (UTC)
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- they wouldn't be "perpetual motion machines" since they don't violate conservation of energy, the energy just comes from the ZPE ;) ObsidianOrder 02:34, 15 March 2006 (UTC)
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- Linas, your assumption that extracting useable energy from the vacuum has to be "something for nothing" strikes me as odd. Solar power, wind power, and tidal harnesses are just as effectively "something for nothing," yet nobody argues that they violate thermodynamics. Forward's device demonstrates that extraction of energy from the ZPF is possible without violating thermodynamics, and this result is confirmed by Cole/Puthoff later. The "zero" in zero-point energy is really arbitrary, with the Dirac Sea, and particular geometrical configurations of matter can create negative energy densities, as in a Casimir Cavity, thus providing a potential energy gradient for energy extraction. DanFarnsy (talk) 21:56, 18 January 2008 (UTC)
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[edit] caption correction
In the equation for the average energy of a harmonic osciallator in the "History" section, the notation "h-bar is Planck's constant" should be "h-bar is Planck's constant divided by 2 pi"
DoctorD 20:57, 13 March 2006 (UTC)
- Yes. linas 01:00, 14 March 2006 (UTC)
[edit] ZPE papers
H. E. Puthoff, "Ground State of Hydrogen as a Zero-Point-Fluctuation-Determined State," Phys. Rev. D 35, 3266 (1987).
Tommy Mandel 08:17, 16 March 2006 (UTC)
[edit] Merge with Vacuum energy
I placed the merge tag on the article. As far as I understand the two articles are about the same issue. The article in fact states: "In quantum field theory, it is a synonym for the vacuum energy...". If the two issues are different, then the articles should make this difference clear. At the moment they do not. They are hardly even aware of each other, except for the "synonym" reference. Petri Krohn 00:52, 29 March 2006 (UTC)
- (I copied this comment from my talk page. Petri Krohn 01:10, 29 March 2006 (UTC))
- Please do not place merge tags on random pages unless you can articulate clear reasons why said articles should be merged. As they appear to be on distinct topics, I see no reason to merge them. Linas 00:26, 29 March 2006 (UTC)
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- I thought the reason is clear, the two words are synonyms (or near synonyms). Also, most article referring to these articles do not see the difference, and the selection as to which to refer to seems to be random. I stated my point by placing the tag. I hope you can state the differences between the two concepts. If there are real differences, then these should be integrated into the articles. Petri Krohn 01:10, 29 March 2006 (UTC)
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- I suggest not merging. I am about to begin reading (next week) Lynne McTaggart’s, top-500 Amazon, book: The Field. I assume the book is going to be a lot of stretched science; hence, as a preliminary, I was doing a Wiki-search for “Zero Point Field”, and I got a redirect here? If I would have gotten a redirect to vacuum energy that would have been totally a dead-end search. --Sadi Carnot 00:22, 30 March 2006 (UTC)
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No to the merge, as the suggestion is based on a faulty premise. The terms "vacuum energy" and "zero-point energy" are not the same. This article explains how these terms differ. You say so yourself: "In quantum field theory, it is a synonym for the vacuum energy..." however, in other caes, they are *not* synonyms. In particlar, simple oscillators have a zero-point energy. Also, there is a concept of zero-point energy in solid-state physics, as the zero-point motion of atoms near absolute zero. Its implicated in sperfluid/superconductivity effects; there is definitely no "vacuum". The term "vacuum energy" applies to quantum fields, and not to individual oscillators. Finally, the idea of "zero-point energy" attrcts a lot of crank science types, I wish to keep these sepeated and corralled in this article, as opposed to letting them run loose through legit articles. linas 01:04, 30 March 2006 (UTC)
- I still think the Vacuum energy contains material that is about/should be in this article. (If we remove all Zero-point energy stuff I do not know if there is very much left.)
- I am making a new merge proposal, this time more spesific: Material about Zero-point energy in the Vacuum energy article should be moved here. Petri Krohn 02:34, 30 March 2006 (UTC)
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- Look, I really don't understand why you are being so pushy about this. Zero-point energy and vacuum energy are not the same thing, and they should not be confused with one another. All I get from your arguments is that you seem to think that they are the same thing. What is the scientific basis for your editorial desires? Do you actually have any credentials in quantum field thoery? For the record, my PhD thesis was on the vacuum energy of the quark field in the chiral bag [6], so I feel that I have a pretty good grasp on the topic. I am not trying to block good edits; I am trying to block edits of questionable merit that do not actually make WP a better place. If you think you can expand one or he other article in some meaningful way, please do so. However, if you cannot, then please desist in dragging on a long argument that has no particular merit. linas 01:36, 1 April 2006 (UTC)
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- Please don't be impatient with us, Linas. Many of us don't have PhD's, and these distinctions are not obvious to us. Your clarifications are most appreciated. However, our name policy says that "Names of Wikipedia articles should be optimized for readers over editors; and for a general audience over specialists." I would say that most readers who look up "Zero-point energy" would be primarily interested in the lowest energy state of vacuum. Petri's original proposal makes sense to me.--Yannick 05:40, 9 April 2006 (UTC)
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These merge requests waste a lot of time for all involved. If the Encyclopedia of Particle Physics (Gibbon, 2000) can have separate, almost full-page, entries on these topics, I don’t see why Wikipedia Encyclopedia can’t as well have separate entries. From what I quickly read, we have two separate non-merge-able topics:
- Zero-point energy is the energy associated with a particle or system, over and above its mass-energy, at the absolute zero of temperature.
- Vacuum energy is the lowest-energy state of spacetime filled with virtual particle energy fields related or due to quantum uncertainty.
Furthermore, whenever someone puts up a questionable merge; then later, down the road, when the article goes over 32 kilobytes, someone else will have to spend time breaking up the article. --Sadi Carnot 23:15, 10 April 2006 (UTC)
- The Encyclopedia of Particle Physics is a specialised text, whereas Wikipedia is aiming for a general audience. I don't have a problem with two separate articles, but I still maintain that Zero-point energy should refer to the lowest-energy state of spacetime, reflecting common usage, or at least to a disambiguation. The zero point energy of an arbitrary quantum oscillator (not spacetime) is a specialised topic of interest to a much smaller audience, so a title such as Zero-point energy (quantum mechanics) would be more appropriate. Vacuum energy would then be merged to Zero-point energy.--Yannick 02:25, 13 April 2006 (UTC)
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- I disagree with the last statement. WP serves not only a general-interest audience, but also high-school students, college students, grad students and working academics/professors/engineers/specialists. In fact, it is the specialized content of WP that is attracting the most capable authors. The article can certainly be written so that it serves the general interest reader as well as the student. I see no point in intentionally using loose language and confusing different concepts. linas 03:29, 20 April 2006 (UTC)
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- In that case, you should propose a change to the name policy. I don't know how strongly people feel about the "general audience" clause, but it's currently part of the policy.--Yannick 03:16, 27 April 2006 (UTC)
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- I'm not proposing a change to the name policy. I am suggesting that just because you mistakenly confuse a Ford with a Chevy doesn't mean that the WP article on Fords should be merged with the WP article on Chevys. linas 03:30, 29 April 2006 (UTC)
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- Let me add some support to Linas. This is a silly discussion, and as an astrophysics student I'm baffled by the request to merge two things manifestly deserving of separate treatment.--astroflyby
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- I'm going to assume that this argument is over (as the last message was in April, it's now July) - I'm going to remove the merge tag as the majority of posts disagree with the proposal. Furthermore, it's just plain silly! Your one true god is David P. A. Hunter, esq. III Talk to me! 09:38, 1 July 2006 (UTC)
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[edit] ZPE vs. ZPF?
Why aren't there pages on both Zero Point Energy [ZPE] and Zero Point Field [ZPF] in WP? Both of these topics are new to me; hence, I am wondering why I have to go "outside" of WP to find information on ZPF? Such as the following:
Can someone explain this to me?--Sadi Carnot 01:27, 12 April 2006 (UTC)
- 1) For whatever social/cultural reasons, the rate of participation by physicists in WP is considerably lower than the participation rate of mathematicians. Many articles haven't been written yet, or are in poor condition.
- 2) Articles on popular or general-interest topics are difficult to create and maintain (witness conversations above). The subject specialists are often overwhelmed by the onslaught of entropy, degeneration and decay, as well-meaning but ill-informed editors make detrimental edits. Its exhausting to monitor these and beat them back. (Its a lot more satisfying to write highly specialized articles; as so the unwashed masses leave one alone. This is why the WP articles on arcane topics are excellent, while those on high-school-level topics are a wasteland of misinformation.) linas 03:52, 20 April 2006 (UTC)
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- I agree; however, a stub on Zero-point field would be nice if you have the time? I may be able to contribute a little if you start it. There are a lot of new age writers out there trying to make a ramshackle connection between the ZPF and concepts like Akashic field, Morphogenic field, The field, Quantum field, Electromagnetic field, etc. Hence, it would be nice to get some straight scoop on the essentials of the topic. Or are ZPE and ZPF the essentially same topic?--Sadi Carnot 18:54, 25 April 2006 (UTC)
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- I redirected Zero-point field to Vacuum state, and gave it a brief definition there. It's a peculiar term, not widely used, but roughly it is the empty quantum field, of which the quantized Electromagnetic field would be an example. Although I admit that, like many, I get a lurid thrill from reading new age philosophy, spiritualism, ESP, UFO's and the rest, and its all quite fun, I'll also be hard-nosed and state that these topics, as well as Morphogenic field and Akashic field, are scientific hokum. Fun hokum, but still hokum. On the other hand, if there is one lesson from science, it is this: truth is stranger than fiction. linas 04:29, 29 April 2006 (UTC)
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- By the way, the two articles that you quote above, on halexandria.org,
appear to be mostly correct,although I did not actually read them. (on second look, they seem to veer off-course a bit). Unfortunately, none of this stuff has any easy explanation, and you really do have to get a graduate degree in physics to understand it. That's just the way it is ... linas 04:34, 29 April 2006 (UTC)
- By the way, the two articles that you quote above, on halexandria.org,
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[edit] Apparent conflict of interest
Several recent anon edits of this article have been made by an anon using the IP 69.107.99.133 (talk · contribs), aka the pltn13.pacbell.net anon. This domain has also been suspected of providing IP anons for Jack Sarfatti. Haisch and Sarfatti do know each other IRL; Haisch apparently resides in Redwood City, CA (in the Southern Bay Area) and Sarfatti apparently resides in San Francisco, CA.
From this edit, it appears that this domain has been used by Haisch (talk · contribs), who has added a citation of
- Haisch, Bernard. The God Theory. York Beach, ME: Weiser Books. ISBN 1-57863-374-5.
and thus would appear to be in real life Bernard Haisch, whose proposals regarding zero-point energy is discussed in this article. If true, this would appear to violate the spirit of guidelines and policies such as WP:AUTO.
See also this edit (which was reverted by someone else before I came along). It appears possible that Haisch was an anon for some weeks before registering, so the anon edits might represent a newbie who didn't realize how these edits would appear once his identity became known. Although, to point out the obvious, from his choice of handle, User:Haisch cannot have been attempting to hide his identity, so these edits, which I think may have been in questionable taste, cannot represent an attempt to shill or anything like that. I've probably been oversensitized by some recent incidents I've noticed which appeared far more sinister. ---CH 02:52, 28 May 2006 (UTC)
See also these articles:
- Digital Universe, a joint venture of Haisch and Joe Firmage
- Stochastic electrodynamics, a fringe theory due to Haisch, Alfonso Rueda, and Harold E. Puthoff
- Vacuum energy
- Polarizable vacuum, a fringe theory of Puthoff
- Institute for Advanced Studies at Austin; see Ibison (talk · contribs) (in real life Michael Ibison, an employee of IASA, whose pages happen to be held at the website of EarthTech, a company founded by Puthoff, but Ibison says these two organizations are otherwise independent; Ibison does seem to have taken the point about the appearance of a possible conflict of interest after I pointed this out)
See also these links:
- The God Theory, web page for the book
- The God theory contents, from the Library of Congress
- California Institute for Physics and Astrophysics, a fringe science organization founded by Haisch
- Freeing Imagination, from theisticscience.org, which rather incredibly is registered to Ian Thompson (Physics, University of Surrey)
- Freeing the Scientific Imagination from Science & Theology News, which is apparently registered in Quincy, MA
- Preliminary Discussion of New Science from pureinsight.org, which is registered in Duluth, GA
- ZPEnergy, website promoting Haisch, possibly registered in British Columbia
- Weird Science, a newsitem about Haisch
I have noticed a recent increase in the frequency of this kind of incident. ---CH 08:31, 25 May 2006 (UTC)
- After a long discussion with some other users, I can see that I probably should have started by leaving a message in the user talk page of User:Haisch, as I did with User:Ibison. Alarmed by the sudden space of related edits by persons involved in this stuff, I may have overreacted to the Haisch edits. I don't yet have a firm opinion about this since I still haven't had a chance to closely examine all the edits not to mention all the relevant eprints. I am formulating a draft guideline to help suggest possible courses of action to future Wikipedians who notice a suspicious pattern of edits, in which I hope to incorporate my discussion with several other users concerning this incident. ---CH 02:36, 28 May 2006 (UTC)
[edit] History section
The following section of the article looked suspect to me, so I moved it here, for discussion:
- ===History===
- The concept of zero-point energy originated with Max Planck in 1911. The average energy of a harmonic oscillator in thermal equilibrium with its surroundings is:
- Here, is Planck's constant, ω is the natural frequency, k is Boltzmann's constant, and T is the temperature.
- At the same time Albert Einstein, L. Hopf (1910) and Otto Stern (1913) were also studying the properties of zero-point energy. Shortly thereafter Walther Nernst (1916) proposed that empty space was filled with zero-point electromagnetic radiation. Then in 1925 the existence of zero-point energy was shown to be “mathematically required by quantum mechanics, as a direct consequence of Heisenberg's uncertainty principle” (which in turn follows from the definition of operators) (Sciama 1991).
This section survives from one of the oldest versions of this article; it was added on 17:16, 19 April 2004 by User:68.166.190.130 in this edit: [7]
The problem here is that these people couldn't have been studying what we call zero-point energy back then, because zero-point didn't exist as a concept until after the formulation of quantum mechanics. This section almost makes sense if we substitute "black-body radiation" for "zero-point energy". Unfortunately, the study of black-body radiation predates Planck; what Planck did in 1911 was to derive a formula for its spectral density.
Of course, Einstein and others were studying black-body radiation at that time; the famous UV catastrophe had been singled out by Lord Kelvin years earlier as one of the great unsolved problems for the 20th century. I'm not at all clear what it is that Nernst may have claimed. The magic unreferenced 1925 date is utterly un-illuminating.
Last but not least, the connection between black-body radiation and zero-point energy in such a historical way is vague at best; a real connection doesn't come until the discovery of Unruh radiation in the 1970's... it seems that there is little or nothing to salvage here that's appropriate for this article. linas 16:22, 27 May 2006 (UTC)
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- Plancks equation really should be explained in the article.
- Here, is Planck's constant, ω is the natural frequency, k is Boltzmann's constant, and T is the temperature.
[edit] Survey of the ten most recent anon editor's contribs
In reverse chrononical order:
- the Dial1.Chicago1.Level3.net anon (possibly somewhere near Cornell, MI) has used
- 4.254.113.242 (talk · contribs) legit addition
- the hstntx.swbell.net anon (registered to Southwestern Bell; geolocated near Houston, TX has used
- 70.253.99.146 (talk · contribs) legit correction
- 65.68.73.156 (talk · contribs) deleted merger suggestion
- the dhcp.sprint-hsd.net anon (possibly somewhere near Kinston, NC) has used
- 71.2.147.254 (talk · contribs) minor legit diction improvement
- the Montreal area Bell Canada anon (near Dorval, Quebec) has used
- 207.164.171.98 (talk · contribs) several rude vandalisms
- the Geneva College anon (near Beaver Falls, PA, which is indeed the location of Geneva College) has used
- 63.172.105.84 (talk · contribs) well-intentioned (?) but questionable edits
- the hsd1.mi.comcast.net anon (near Grand Rapids, MI) has used
- 24.11.20.99 (talk · contribs) added a cultural reference
- the dynamic.dsl.as9105.com anon (registered to Tiscali UK Ltd; geolocated near Manchester, England) has used
- 88.104.215.225 (talk · contribs)
tried to introduce minor but easily overlooked vandalismlegit correction
- 88.104.215.225 (talk · contribs)
- the exetel.com.au anon (registered to Exetel Pty Ltd.; geolocated near Sydney) has used
- 220.233.16.174 (talk · contribs) added a cultural reference
- the demon.co.uk anon (registered to Demon Internet's ADSL Service; geolocated near Eastbourne, England)
- 80.177.20.202 (talk · contribs) added apparently legit paragraph
- the btcentralplus.com anon (British Telecom; geolocated near Bournemouth, England) has used
- 81.153.28.94 (talk · contribs) added inappropriate link to the website of one Robin Jones (curiously enough, there is a Robin Jones' Latin Jazz Sextet based in Bournemouth)
This gives
fivesix who made legitimate edits,- two who made questionable but probably well-intentioned edits,
threetwo who made bad edits.
Much better than any results I've seen so far in similar survey! Helpful anons, thanks, and please help us keep the nasty anons in line by reverting obvious vandalism, etc.! ---CH 22:07, 4 June 2006 (UTC)
- An interesting survey with encouraging results. I'd like to make a comment in defense of the Manchester, England anon, numbered 7 above. As the article on Planck's constant makes clear, the constant is given in two forms. The usual Planck's constant is 2π times bigger than the so-called reduced Planck's constant; the former is written with an ordinary letter h, while the latter is written with an h plus a crossbar. So rather than subtle vandalism, the anon was exactly right: h-bar is (the unreduced) Planck's constant divided by 2π. If my understanding is right, this changes the stats to 6, 2, and 2, rather than 5, 2, and 3. Oh, and we should put the 2π back.
You are quite right; basically, I misread [[Planck's constant]/2/π as 2 π.---CH 17:59, 5 June 2006 (UTC)
- Right; the anonymous editor did flub eir markup, by getting the /2π inside the outer pair of wiki-brackets (does anybody else call these "wickets"?), which made it hard to see what was going on. Anyway, an editor deemed the whole section dubious, and moved it to this talk page, so the question is moot, at least for the moment. (And thank for covering for me forgetting to sign.) ACW 12:00, 6 June 2006 (UTC)
[edit] Edit by the Tele Norge anon
193.216.163.239 (talk · contribs) (Tele2 Norge AS. Dynamic IP pool near Oslo) added this paragraph:
"Despite these circumstances, the search for devices tapping the zero point energy has a certain fundamental scientific basis, given that in the Casimir effect, zero point energy is translated into work on the macroscopic scale by the movement and welding-together of the metal plates. Those supportive of the idea of free energy devices argue that although the zero point energy may or may not be removed from the system, it is already proven to do actual work in physical experiments, and hence is a viable area of research."
Tele2 Norge, can you explain what you have in mind? If zero-point energy cannot be removed from "the system", how can it be used to generate electric power or whatever? (I.e. transmitted over power lines to light a bulb in someone's study.) ---CH 07:17, 17 June 2006 (UTC)
[edit] Article's statement not entirely clear
The article states, without any explanation
- "Because zero point energy is the lowest possible energy a system can have, this energy cannot be removed from the system."
And goes on to prove from that that no device could ever "tap" a particles zero-point energy, or extract energy from it. However, to a non-physicist, this doesn't seem entirely obvious. If a trapped elementary particle is required by Heisenberg's principle to have some finite momentum, then it would seem to me (a non-physicist) that it's momentum could never-the-less be lowered, without it ever hitting zero. That is, Heisenberg's principle doesn't appear to state that the particle's momentum must necessarily be the smallest possible momentum of that particle.
This isn't to say that anything in the article is incorrect, just that it doesn't make clear why this is not the case. Could some explanation for the statement quoted above be inserted? — Asbestos | Talk (RFC) 16:58, 22 June 2006 (UTC)
[edit] Don't forget to Spellcheck
The header "Fondational Physics" does not do wonders for your credibility. Use your spell-checker!
[edit] Pop Culture References List
Can we add a popular media sightings section? Although this would allow a non scientific section to an all physics page, zero point energy IS very widely recognised as one of the most falsified claims by fakers (perpetual motion and free-energy machines)
If so, I offer my sighting - The Incredibles, Pixar film, Buddy Pine/Syndrome has created a zero point energy wrist weapon.
- See Zero-point energy in popular culture, which should be summarized in a section of this article, if you ask me.--Yannick 02:54, 15 September 2006 (UTC)
[edit] Two more references:
Also your link seems to go to a nonexistent page, with no new section in this article either.
Kd5npf (talk) 04:38, 16 March 2008 (UTC)
[edit] Weblinks
The article has four sections about physics and a (as usual) rather messy "free energy" section. But the "external links" contains almost exclusively dubious "free energy" sites. As my first removal of these got reverted, I wanted to point this out here. Also, I've shortened the "free energy" section. This topic can be covered at free energy suppression and Perpetual motion. --Pjacobi 10:01, 22 November 2006 (UTC)
Have re-added the stuff on propulsion with references from physics institutes and NASA please leave it in this time as it is relevent to the topic and is not fringe science. Rob
[edit] Merge Null oscillations into this
I think the Null oscillations page should be merged into the Zero-point energy page; unless that article is expanded to show how it is different from ZPE, it appears to be about the same thing. -- Whitepaw 22:15, 30 December 2006 (UTC)
- I simply redirected, there was nothing to be saved. linas 16:00, 22 May 2007 (UTC)
[edit] Lowest state of energy ?
I understand that zero point energy is not a usable energy source. Energy can not come out of it, its no perpetuem mobile.
Its a state discription and not a flow or drain where our energy can freely endup
But in physics particles can arise from nothing in a vacuem, together with their anti particles. At the quantum scale this happens so frequently that our world as we know it would not exist without this effect. Altough even hard to imagine to me, those 'virtual' particles are needed in the quantum mechanics world.
The Einstein formula is an 'atomic' formula not a quantum formula.
So does this concept of zeropoint energy only aply to atom physics in the old physics model ?
Or is zero point energy not that zero perhaps a noisy zero As other wise i cannt imagine what would drive these virutal particle creations. If that is true what would then be the 'new' Quantu mechanics (QM) concept of the lowest energy state of an cubic empy space of a given size?. —The preceding unsigned comment was added by 82.217.143.153 (talk) 15:00, 12 March 2007 (UTC).
- You are attempting to distinguish "first quantization" (sometimes called "atomic physics") from second quantization, which is the quantization of fields. This is a good distinction to make. The idea of a zero point energy appears in both, although in dramatically different form in each. linas 16:04, 22 May 2007 (UTC)
[edit] Graphs in history section?
12:05, 17 March 2007 91.153.144.149 wrote in the history section: Why not add a graph of these functions, to visually descrbe the behaviour of the "energy radiator"? It would make this article much less dry and lifeless. Martin62 01:34, 18 March 2007 (UTC)
[edit] Casimir Effect not proof of ZPE
Although the Casimir Effect was postulated on the hypothesis of ZPE, there are other explanations for the effect. R Jaffe, at MIT, recently argued that it could be explained in classical E/M terms. See http://arxiv.org/abs/hep-th/0503158.
Maybe the section that mentions Casimir should be a litle more circumspect on this. --lutin 21:43, 25 April 2007 (UTC)
- I skimmed the preprint, and Jaffe is, in a certain sense, correct. The Casimir effect is "just" a one loop correction, just as the Lamb shift is, or other common one-loop corrections. The cosmological vacuum energy is a different beast. Surely, even Steven Weinberg would agree; unfortunately, in the past, Weinberg, along with almost all traditional, mainstream authors, have helped confuse the concept of a one-loop correction with the concept of the vacuum state: and for good reason, as they are not unrelated. However, untangling these properly, and doing so in a forum like wikipedia, may prove somewhat difficult. So while Jaffe has a point, its may be too subtle to try to incorporate this into the current article. linas 16:18, 22 May 2007 (UTC)
[edit] Rewrite rejected
I tried to rewrite this article to clarify the whole Casimir thing. Casimir forces are Van-Der Waals forces in the limit that the separation of objects is big enough. Big enough is compared to the distance light travels in a typical excited state period. This is the difference between London force and Casimir force, and this is what Casimir calculated in 1947.
The casimir force can be calculated as the difference in zero point energy of the electromagnetic field in different boundary conditions. All these boundary conditions do is take into account the different polarizabilities of the different materials which are now too far to be entangled. So they contribute a local boundary condition to the E-M field, and the attraction becomes universal.
That this calculation can be calculated from differences in the field energy in different boundary conditions is not contested. But the idea that this tells you something about the vaccuum energy is ridiculous. The vaccuum energy can always be defined to be zero, and only differences between different states are defined. The different states are different boundary conditions.
Perhaps it is impossible to get this page changed to reflect these facts. But they are facts, and they will not change.Likebox 21:09, 8 September 2007 (UTC)
[edit] too technical
Yes, I can't for the life of me understand this article, as I am not a PhD quantum physicist. Unless there's no way to describe it in layman's terms without first learning about all the terms it discusses and spending years in university this belongs in a science wiki somewhere. Anyway, this is what I wanted to find out http://www.nasa.gov/centers/glenn/research/warp/possible.html.
“ | Zero Point Energy (ZPE), or vacuum fluctuation energy are terms used to describe the random electromagnetic oscillations that are left in a vacuum after all other energy has been removed. If you remove all the energy from a space, take out all the matter, all the heat, all the light... everything -- you will find that there is still some energy left. One way to explain this is from the uncertainty principle from quantum physics that implies that it is impossible to have an absolutely zero energy condition.
For light waves in space, the same condition holds. For every possible color of light, that includes the ones we can’t see, there is a non-zero amount of that light. Add up the energy for all those different frequencies of light and the amount of energy in a given space is enormous, even mind boggling, ranging from 10^36 to 10^70 Joules/m3. In simplistic terms it has been said that there is enough energy in the volume the size of a coffee cup to boil away Earth’s oceans. - that’s one strong cup of coffee! For a while a lot of physics thought that concept was too hard to swallow. This vacuum energy is more widely accepted today. |
„ |
I don't see how they relate, what energy are they talking about that is this 10^36 to 10^70 joules/m3 what does it have to do with zero point energy? Anyway, I wonder what could be done with that energy if could harness it, if it could be used for making wormholes and the like, or getting a ship up to near light speed The snare 07:44, 10 September 2007 (UTC)
- This is the central problem with this article--- it misinforms almost purposefully. The zero point of energy is, putting gravity aside, a matter of convention. I could say that "empty space has 50 zillion megajoules per micron cubed" or I could say "empty space has 0 energy", or I could say "empty space has minus 50 zillion megajoules per micron cubed" and I would be right.
- Gravity changes things, because energy makes gravity. So if there's gravity you can measure the energy content of empty space. This is called the "cosmological constant", or the "dark energy", and it is measured to be very close to zero, but not quite. This is not important for anything on this page.
- It is not possible to harnass the energy in space, because to harnass the energy you need another state where there is less energy. You get energy when you move something from a state where it has high energy to a state where it has low energy. In order to harnass the energy of space, you would need to be able to change space to a state of lower energy. If this were possible, nature would have done it long ago, nucleating a bubble of "true vaccuum" out of quantum fluctuations, and destroying our universe.
- But when you look at empty space, there are things in it. This is a fact, and nobody contests it. The things we know about in empty space for sure:
- 1. Pion condensate--- there's a bunch of quarks and antiquarks which have made a relativistically invariant superfluid in which everything sits. This superfluid is detectable because it shakes, and the shaking we call "pion emmission". This was discovered by Nambu in 1960. Nobody contests this. The energy density of the pion condensate can be estimated by the difference in energy between different values, and its something like 100th of a nuclear mass in every nuclear volume, where a nuclear mass is the mass of a proton and a nuclear volume is the volume of a proton.
- 2. Higgs--- there's a field in space which gives everything mass. We know it's there because the ratio of the mass of two particles, the W and the Z, is predicted with perfect accuracy by assuming they both get their mass from this field. The masses of the quarks and electrons and the masslessness of neutrinos is completely explained by the interactions with this field. No doubt about this one either. Although you could think maybe it's made of some new "techniquarks", like the pion condensate is made of quarks, but who knows. We'll measure it soon.
- 3. Flucuation energy--- If we look at fields in space, we see that they have fluctuations. What that means is that it is impossible to have zero electric fields and magnetic fields at the same time, by the uncertainty principle. Electric fields and magnetic fields are complementary, because the electric field and the vector potential are like position and momentum. So there's energy in these fluctuations, which is naively infinite.
- But again, since only energy differences are defined, there is no way to harnass any vaccuum energy unless you have another state to move the vaccuum into. There is no such state. For example, maybe there's an enormous value of the Higgs field where it has slightly less energy than in our universe. Then the universe would be unstable to nucleation, a process where a big bubble of Higgs in the true vaccuum would be formed.
- This page is concerned with producing the misimpression that vaccuum energy means something else than what it does. It is trying to make it sound like you can run your car on empty space. This is unfortunate, because it associates the name of a good honest physicist (Casimir) with a radical and implausible idea that I don't think he would ever hold.Likebox 01:39, 11 September 2007 (UTC)
You said we would have to be a lower point than zero point energy to be able to use it, but isn't that possible if we are at a negative energy state? Just asking here, don't really know, but does the Casimir effect show that negative energy does exist when you put two uncharged plates so close together that not even an atom can fit between them, that there will be "less than nothing" between them, causing them to be pulled together?
Here's something else I thought of, what if you had several uncharged plates at that distance from each other, but they were firmly attached to the ground/surface, etc. So that it could try to pull them together but couldn't? The snare 02:05, 12 November 2007 (UTC)
- You can't get to a negative energy state - that's the entire point. Now, the Casimir effect pulls two plates together because there are fewer virtual particles between them than outside, but that doesn't let you do work - you can make a very lousy battery by pulling the plates apart, doing work in the process, and holding them there, then letting them collapse back when you want to get the energy out. Michaelbusch 04:05, 12 November 2007 (UTC)
You can get a negative energy state if you define regular open vacuum to be the zero state. In the consideration of zero-point fields as electromagnetic radiation (uniform and Lorentz invariant, therefore undetectable), then lower frequency radiation is forbidden between two conductive plates due to its long wavelength. Thus, the energy density between the two plates is negative if open vacuum is zero, since the lower end of the spectrum is forbidden. It's this difference in energy densities that pushes the plates together. It's pure speculation on my part that the enormous density of the zero-point energy doesn't make the universe collapse on itself because the zero-point field is the ether (again, Lorentz invariant), and gravity is only mass perturbations of the zero-point field. I'm not sure about what utility that point of view has. However, it's clear that specific boundary conditions change the behavior of the vacuum energy which has physical consequences, like the Casimir effect.DanFarnsy (talk) 12:35, 17 January 2008 (UTC)
[edit] may be helpful, may be not
http://www.newscientist.com/channel/fundamentals/mg18925331.200-take-a-leap-into-hyperspace.html
Does Burkhard Heim's work have anything to do with zero-point energy? --Emesee 15:31, 10 October 2007 (UTC)
[edit] Might be neat
It might be neat to include some popular/news references to Zero Point.
I know Tori Amos has a song called Zero Point and I've heard it a few other places. —Preceding unsigned comment added by 161.38.223.228 (talk) 23:38, 22 October 2007 (UTC)
Other references include the Zero-Point Energy Field Manipulator, or gravity gun, from Half-Life 2, and the weapon of choice of the main villain in The Incredibles, if the references are ever added. They're actually the reason i looked this up. If references are NOT ever added, then just ignore this. --IntriguingPotato (talk) 21:36, 23 December 2007 (UTC)
[edit] Dark Energy is not Vacuum Energy
The term "dark energy" is associated with an unknown energy that has been found to be accelerating the expansion of the universe. This term was coined around 1998 when the effect was discovered from measuring the distance to supernovas of a type with a known brightness, and measuring their red shift, whereas quantum field theory dealing with vacuum energy started in the 1930s and 40s. These are separate ideas and should not be conflated.
The predicted (though probably wrong) energy of the ZPE is over 10^100 times more than it should be according to the CC. However the dark energy, including the energy in dark matter (another subject) is only 10 times more than CC predicts. These are very different things, nor should one automatically assume just one or the other is the real answer to the ZPF energy question. It deserves far more thought than a quick off the cuff answer. 75.6.245.24 (talk) 06:05, 10 January 2008 (UTC)
Part of Bernard Haisch's theories, IIRC, is that the vacuum energy/fields can provide a mechanism for acceleration of particles in the cosmic voids, like cosmic rays at 10^21 eV, and also claims that this accounts for apparent acceleration of expansion without a need for invoking vague (but popular) dark energy. The status of this is speculative, but does provide a potential link between dark energy and vacuum energy. DanFarnsy (talk) 12:42, 17 January 2008 (UTC)
[edit] Removed uncited paragraph
I have removed the following paragraph from the article, because it is uncited.--Srleffler (talk) 04:43, 15 April 2008 (UTC)
Another area of research in the field of zero point energy is how it could be used for propulsion. NASA and British Aerospace both have programs running to this end though practical technology is still a long way off. For any success in this area, it would have to be possible to create repulsive effects in the quantum vacuum, which according to theory should be possible and experiments to produce and measure these effects are planned for the future.