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Archive 1 | Archive 2 |
This is pretty much a ramble showing the sort of thing that might be included. I find that in conversation with smart non-physicsts, they light up when I can get the unifying reason for using the concept of energy across to them.
There might be better examples to include, a satellite launch lower bound is orders of magnitude lower than practice, maybe energy in oscillators (pendulum, LC etc) would be good.
What do you think?
A Noob's first wiki contribution. Sorry about the link out to a new page, I didn't spot the next section [+] until I came to this Talk area, too late at night to change it now. NeilUK 00:39, 11 January 2006 (UTC)
Sigh.... Terry King 23:25, 26 February 2006 (UTC)
My history of physics is a bit rusty, but if I remember correctly, didn't Huygens first suggest a way of quantifying kinetic energy (albeit not knowing it was energy)? As I recall, he felt the need to introduce a new scalar quantity for mechanics. And then didn't Young find that work equals the change in energy? I felt compelled to suggest this, as the history section is a bit nebulous when it comes to the history of the topic before thermodynamics. Gershwinrb 07:36, 27 February 2006 (UTC)
this link in the bottom of the page:
What is that? it's a page full of ads with a very doubtful photo of what seems a spot on the lens of the camera and claims to be an "energy ball"
It's obviously a marketing trick. I think it should be removed right away. I don't do it myself cause i'm just a newbie, who just happened to reafd the article, and i leave it to discussion.
Apologies to all the scholars; this is a question from the masses...
The initial definition of energy appears to be a description of how matter behaves; not a definition of energy in its own, intrinsic nature. If I accept this definition; then energy has no individual existence - it is merely a concept of activity, a way to place a generic definition on the many ways in which matter can and does interact with itself.
Following on from this (pardon the macro-leaps in logic) if quantum particle physics claims that matter seems to be a result of the interaction of energy, confined into extremely small, relativistic volumes of space/time - this would suggest that energy is the action of matter; that (in itself) is the action of energy confined; that is matter in action; that is energy confined.......
See my dilemma?
Can Science actually explain to me: What is matter and what is energy, without referring one to the other? To explain away the actual definition of matter, by suggesting that it is some form of 'confined energy' - simply places the responsibility back on science to define energy. However, as energy seems to be defined as an action of matter -- you can see why I am dissatisfied with this definintion.
Please note; This is a genuine request for further explanation. I am not being silly. I am an individual who represents the readers/consumers of the Wikipedia experience. Although I appreciate the depth of knowledge being provided for me to use; I feel that there is both room for scholars to better explain their claims to the uninitiated AND use this forum to carry on their important work at the forefront of human knowledge. Sincerely, Greg Chalmers. cool!
---unfortunately, the only way to define energy is by mentioning matter. I know this may bug you but there is a reason: energy is relative. Think of it this way: from the frame of a person standing on the road, a truck has huge amounts of energy, this energy can only exist because the truck has mass. To say that anything relative to anything else has energy, that thing needs to have mass. In fact, Einstein noticed this relationship and found that mass itself is energy. The formula "E=mc(sq)" states that all matter is energy. In the same sense that time was found to be another dimension like space, space and time became the space-time, when mass was found to be another relative view of energy, mass and energy became mass-energy. Energy is nothing more than what matter is doing compared to what you are doing.
DEFINITION of ENERGY: "Energy is a fundamental property of a physical system and refers to its potential to maintain a system identity or structure and to influence changes (via forced interaction) with other system by imparting work (forced directional displacement) or heat (forced chaotic displacement/motion of a system molecular or related structures). Energy exists in many forms: electromagnetic (including light), electrical, magnetic, nuclear, chemical, thermal and mechanical (including kinetic, elastic, gravitational, and sound), where, for example, electro-mechanical energy may be kinetic or potential, while thermal energy represents overall potential and chaotic motion energy of molecules and/or related micro structure. "... Energy is the ‘‘building block’’ and fundamental property of matter and space and, thus, the fundamental property of existence. Energy exchanges or transfers are associated with all processes (or changes) and, thus, are indivisible from time." by M. Kostic: "Work, Power, and Energy" article in the Academic Press/Elsevier's Encyclopedia of Energy < http://www.kostic.niu.edu/energy>
See: [1] Also see: [2] and [3]
World Energy: At present, most of the World energy consumption is supplied by the fossil fuels (about 85%). However, the proven fossil fuel reserves are limited, and if continued to be used at the present rates, it is estimated that the coal (as used under current conditions) will be depleted in about 250 years, oil in 60, and natural gas in about 80 years. We have to keep in perspective that ‘proven reserves’ refers to the customary and economical ‘mining’ and utilization of fuels, but new reserves and more efficient technologies are being discovered, and make new fuel reserves economical. At present, a substantial amount of World electricity is obtained from nuclear and hydro energy, about 17% and 18%, respectively, and use of other renewable energy resources is increasing, namely geothermal, wind, biomass and solar, as well as development of alternative synthetic fuels, including development of hydrogen fuel cells, etc. It is worth noting that some countries produce almost all or most of their electricity from hydro energy (like Norway, Brazil, New Zealand, Austria and Switzerland), and France produces most of its electricity from nuclear fuel (76%). The nuclear fuel reserves are orders of magnitude higher than fossil fuels, and it does not contribute to CO2 and green-house pollution.
Furthermore, advances in energy conversion and utilization technologies and increase in efficiency, including computerized control and management, contribute to energy conservation, increase in safety, and reduction of related environmental pollution. Actually, per capita energy use in the U.S. and other developed countries is being reduced in recent years. However, the increase of World’s population and development of many underdeveloped and very populated countries, like China, India and others, will influence continuous increase of the World energy consumption.
Energy Future Outlook: The two things are certain: in not distant future (1) the world population and their living-standard expectations will substantially increase, and (2) fossil fuels’ economical reserves, particularly oil and natural gas, will substantially decrease. The difficulties that will face every nation and the world in meeting energy needs over the next several decades will be more challenging than what we anticipate now. The traditional solutions and approaches will not solve the global energy problem. New knowledge, new technology, and new living habits and expectations must be developed to address both the quantity of energy needed to increase the standard of living world-wide and to preserve and enhance the quality of our environment.
A probable scenario … in the wake of a short history of fossil fuels’ abundance and use (a bleep on a human history radar screen), the following energy future outlook is possible:
1. Creative adaptation and innovations, with change of societal and human habits and expectations (life could be happier after fossil fuels’ era)
2. Intelligent hi-tech, local and global energy management in wide sense (to reduce waste, improve efficiency and quality of environment and life)
3. Nuclear energy and re-electrification for most of stationary energy needs
4. Cogeneration and integration of power generation and new industry on global scale (to close the cycles at sources thus protecting environment and increasing efficiency)
5. Energy conservation and regeneration have unforeseen (higher order of magnitude) and large potentials, particularly in industry (also in transportation, commercial and residential sectors)
6. Renewable biomass and synthetic hydro-carbons for fossil fuel replacement (mobile energy, transportation, and chemicals)
7. Advanced energy storage (synthetic fuels, advanced batteries, hydrogen…)
8. Redistributed solar-related and other renewable energies (to fill in the gap…)
However, the outlook for future energy needs is encouraging. There are many diverse and abundant energy sources with promising future potentials, so that mankind should be able to enhance its activities, standard and quality of living, by diversifying energy sources, and by improving energy conversion and utilization efficiencies, while at the same time increasing safety and reducing environmental pollution (by M. Kostic).
M. Kostic, Treatise with Reasoning Proof of the Second Law of Energy Degradation, Manuscript, Northern Illinois University, 2006.
M. Kostic, Treatise with Reasoning Proof of the First Law of Energy Conservation, Manuscript, Northern Illinois University, 2006.
"A new scientific truth does not, generally speaking, succeed because the opponents are convinced or declare themselves educated, however because they die and the new generations from the beginning learn about it as the truth." by Max Planck (+) [at: Electrons.html ]
M. Kostic, Energy: Global and Historical Background, Manuscript for Encyclopedia for Energy Engineering and Technology (B. L. Capehart, Editor)], Taylor & Francis/Dekker, 2006.
M. Kostic, Energy: Physics, Manuscript for Encyclopedia for Energy Engineering and Technology (B. L. Capehart, Editor)], Taylor & Francis/Dekker, 2006.
Kostic, M., Irreversibility and Reversible Heat Transfer: The Quest and Nature of Energy and Entropy, IMECE2004, ASME Proceedings, ASME, New York, 2004.(ppt)
Kostic, M., "Work, Power, and Energy," Encyclopedia of Energy (C.J. Cleveland, Editor-in-Chief), Volume 6, pp. 527-538, ISBN: 0-12-176480-X, Elsevier, 2004.
Proposal : | Energy (physics)/Archive 2 → Energy (Physics) |
Rationale : | At the moment the title is too general, and the article is tainted with off-topicness about emotional energy and human energy supply. |
Proposer : | User:DavidHOzAu |
I agree to the proposal, with a minor correction, let there be a general page, for example, that on action, with links to various pages dealing with specific contexts. Charlie 09:12, 18 April 2006 (UTC)
Please add * Support or * Oppose followed by a brief explanation, then sign your vote using "~~~~".
Interestingly, majority of voters also suggested creating some sort of disambiguation on the topic. As per WP:D#Primary topic, Energy (physics) will redirect to Energy, and the top of this article will contain a note about Energy (disambiguation). -- DavidHOzAu 11:16, 28 April 2006 (UTC)
I have created
Energy (disambiguation) as a simple redirect to the Energy category for the time being, as that contains virtually the same information. If one
edits that page, you will see some starter text there for the disambigation. It is in need of someone with more experience creating disambiguation pages to further expand the text that is there. I'd have a more sophisticated hack at the page myself, but it is almost bed o'clock where I live. --
DavidHOzAu
12:53, 28 April 2006 (UTC)
Get the details here. The beginning was too unweildy, so I cleaned it up to just a raw definition, moved the remaining content to a new section, and glued the paragraphs together to make it more readable. -- DavidHOzAu 13:27, 11 April 2006 (UTC)
I have been attempting some cleanup lately. I believe that any word is not a propriety of any community. Discussions, about this page are often biased in favour of reserving its usage in the context of physics. I would advocate, an inclusive and comprehensive discussion of the use of the word, as it is used in various contexts, physics, technology, economics and spiritualism. Wikipedia should not repeat what is available in any textbook of physics, it has a much wider readership and contributers should keep that in mind. Too often, topics get biased in favor of a particular community. Charlie 09:24, 18 April 2006 (UTC)
To mathematicians, engineers, physicists and scientists, the word "energy" has a strict and quantifiable definition. Mixing of the non-scientific and scientific definitions of the word is deprecated and leads to confusion. Despite this, the fact remains that the word Energy is often used in contexts that are not as specific as the natural sciences.
For example, in the context of economics, the term energy is used in discussions related to resources, such petroleum products and electric power generation that enable us to use machines.
In the context of psychology, sociology, politics etc., energy can be in in the form of emotional energy, embodied energy, and perhaps psychic energy.
In the context of colloquial language, that is in common speech, the word energy is used to describe the behaviour of individuals. This may be similar to the physical use of the term work (force x distance), although this form is in fact quite different. Energy can be used to describe someone with a vigorous, enterprising, hard working or ambitious drive, or to describe someone’s physical and mental capacity when applied to a particular activity, or to describe someone with an vivid imagination implying vitality and intensity of expression. Similarly, The term "energy" is widely used in a spiritual or non-scientific way that cannot be quantified or even defined. The term energy, in such contexts, is used in traditional and New age mysticism and in fields such as parapsychology, acupuncture, IRECA method and reiki, prana anf yoga. Paranormal researchers will often refer to " psychokinetic energy" when attempting to explain paranormal phenomena or the concept of a spirit or soul. These forms of 'so called' energy are not quantifiable and are therefore unacceptable to the scientific community.
In traditional Chinese culture, energy is referred to as Qi.
Also, In my opinion, physical energy is the most common meaning when people think of energy, the article should focus on that -- Sullevon 17:40, 29 April 2006 (UTC)
There was a hidden comment at the top of the article that removing the link to Energy (disambiguation) was vandalism. However, that page is now a redirect to Category:Energy. Also, there is no meaning of the word "energy" which is not covered by the article. So, I think I'm removing it for good reason. -- Beland 01:49, 7 May 2006 (UTC)
Please see WP:DAB. The disambiguation is going to be there eventually, especially when someone fixes up Energy (disambiguation) sot that it is not a redirect and looks like the Rome (disambiguation) page. Better get used to it now. -- DavidHOzAu 05:59, 7 May 2006 (UTC)
As Energy (disambiguation), thanks to me. -- DavidHOzAu 07:12, 7 May 2006 (UTC)
I like the disambiguation page but it should be here under the main Energy article and this article sould be under Energy(physics). An encyclopedia should educate a reader to all uses not direct them into on particlar use. The current arrangement is a kind of POV pushing. Lumos3 08:16, 18 May 2006 (UTC)
Where should this equation go:
Where P=Power and t=Time? Isn't kind of crucial in showing how electrical and kinetic energy can be connected?-- The i kiro id ( talk)( Help Me Improve) 03:22, 19 May 2006 (UTC)
So should I add it in under something like "Electrical energy?"-- The i kiro id ( talk)( Help Me Improve) 20:49, 19 May 2006 (UTC)
from an inexperienced wikipedia user - under the heading Work, its stated that F=-mg. Now this is incorrect because the vector quantities F (gravitational force) and g act in the same direction. If down is taken as the negative direction then g=-g, F=mg and F=-mg. Right?
I am not sure about the context, but Acceleration has "speed change" and "direction", and is a vector in and of itself. It is convention that g always points to the local gravity sink, so I would think that the article best be changed to reflect convention. -- DavidHOzAu 06:03, 5 June 2006 (UTC)
This article was nominated for inclusion into the Version 0.5 release of Wikipedia, but it was failed due to a complete lack of references. Tito xd( ?!? - help us) 05:55, 31 May 2006 (UTC)
Consider an ideal monatomic gas in a container. If it is allowed to do (adiabatic) work on a piston (ie, it is transfered out of the system as work), the gas cools (loses thermal energy) by exactly the amount of work done on the piston. This does not represent an example of previous potential energy storage in the gas, since all energy transfered to the piston has come out of KINETIC energy of the gas molecules. No potential energy is involved at all, and the whole process only proceeds spontaneously because the amount of entropy created in expansion, is equal or more than the amount of entropy destroyed when the heat is destroyed to become work.
This process can be reversed, but not spontaneously. Work can be done to push the piston back in to compress the gas adiabatically, and in that case the work appears as heat (which again increases entropy over all). But again it's all kinetic energy (monatomic ideal case) and no potential is involved.
You'd think that rubber as in a rubber band would be a good example of potential energy due to intramolecular forces in the band. For a metal spring this is approximately true, but for a rubber band, it's not. Rubber acts very much like an ideal gas, evolving heat at about equivalent to work done on it, and absorbing heat with work that it does. Thus, no work is ever stored as potential or released from potential, unless you cause the heat to remain in the rubber and count the 50% of heat in solids which is potential. But even that isn't stored as potential if you isothermally cool the rubber as it is being stretched (say, with a flow of ideal gas), or isothermally warmed it as it is doing work. Which is to say that the rubber itself simply converts heat to work (and vice versa). If heat is supplied or conducted away isothermally, the rubber band stores no energy as potential at all, like the monatomic ideal gas.
Careful consideration of free energy will show that this can only be possible if the rubber has a lot of internal entropy change associated with stretching or de-stretching, such that the TΔS term is so large that all W can appear as Q. When rubber is stretched the isoprenoid polymers are pulled into alignment, and the methyl groups line up to look more like a crystal. This causes so much entropy decrease that all the work must appear as entropy-increasing heat, to make up for the TΔS. Thus, none can be stored as potential. The same happens on de-stretch.
All of this makes a nice illustration of why energy per se doesn't drive natural processes, and not even energy conversion to heat, if what is stored is "orderliness". A stretched rubber band can do work, and absorb heat to do it with. That's only possibile because a stretched rubber band is essentially a reservoir of stored LOW ENTROPY, not stored potential energy. Sbharris 22:17, 8 June 2006 (UTC)
The definition of energy, located at conservation of energy, is just plain wrong. It says that any transfer of energy results in a change in entropy. Entropy changes according to the Gibbs equation, which for a simple compressible system contains two terms, (1) work; and (2) the change in the internal energy. If these two terms are equal and opposite, the process is isentropic. Adiabatic expansion involving work being performed by the system on its surroundings will produce no change in entropy. -- PotomacFever 15:13, 28 June 2006 (UTC)
The description of the expanding universe found at Energy in Natural Sciences as it relates to entropy is not correct. Here's the passage:
I'd suggest we make these fixes to the above passage: (1) Since I'm not sure that "spontaneous diffusion of concentrated energy" is widely used, I'd suggest it would be better to describe the phenomenon as the expansion of the cosmic background radiation, which is the remnant of the matter-energy decoupling that occurred when the universe cooled to a temperature of 3000K. Since that time, the universe has been coextensive with a photon gas in frozen thermal equilibrium and whose wavelengths therefore fit a Planck distribution (see Planck distribution.) (2) Increased volume does not necessarily lead to increased entropy. For the expansion of the universe in particular, it would not be correct to say that entropy inceases owing to the "diffusion of concentrated energy into the volume available to it." (This last locution could be improved to say that the photon gas which comprises the Cosmic Background Radiation undergoes adiabatic expansion.) Adiabatic expansion would leave entropy unchanged.
I don't mean diffusion "powers" as in provides power for. I meant "drives". Most energy transformations in the universe are irreversible (entropy increases) and what drives them is their very irreversibility-- once they happen, they can't go back. We can say entropy increase drives these transformations, and that's the shorthand. If you want to say something more you need a brief description of entropy, or the kinds of things that entropy increase causes. Energy turns into heat and from that state, some of the energy must STAY as heat. Energy diffuses into volumes and some must then stay diffused. Radiation thermalizes and then is stuck as black body radiation. Heat flows from high to low temperatures (high to low energy concentrations) and then cannot flow back. And so on. It does no good to say that energy "transforms." WHY does it transform and why is it still transforming? I had something to say about that in the original version of the article (basically, it's because the big bang created volume faster than energy could equilbrate within it), but it got reverted. That's bad Wikipedia style-- the rule of Wikipedia is: Don't delete, improve. If you don't like my explanation and delete it, it's becoming on you to do better. Then I'll critique YOU. Energy transformation happens for a reason. You don't like my explanation, then have at it yourself. But simply blanking out my explanation and NOT providing your own substitute, is not much better than vandalism. I fully admit I may not explain it perfectly, but my explantion was certainly better than none, and none is what we presently have. S B H arris 21:08, 15 August 2006 (UTC)
Ireally do not understand the sentence "Energy also tends to be converted into heat over time, and part of this process is irreversible." Is energy different from heat. So far as I know heat is another word for thermal energy, a form of energy. Charlie
Were you talking about me when you said It appears some users believe that they can have an unchecked free run, that is they can make any inaccurate statement and get away with it.? What was inaccurate about what I said? I've said what was inaccurate about what you've said. It was simply wrong. Contact you? Here's your contact. You say it's "childish" to assert that heat is not a form of energy like any other form? Again, your adult explanation will be most amusing. But you owe us your best scientific explanation, not petulant reversions and deletions. And please leave out the unfactual "fixes" this time. S B H arris 05:00, 22 August 2006 (UTC)
Whatso ever editing I did is a result of many years of experience in science communication and not because I hold a PhD degree in science. 59.180.234.124 04:09, 19 August 2006 (UTC)
If one puts a small amount of perfectly pure water vapor into a container and waits, after a time a tiny amount of H2 and O2 will appear, and heat will be absorbed to form them, and the system will cool. WHY? Once the reader understands this, the reader will understand that reactions happen for reasons other than heat, and that not all energy winds up as heat. One can wait as long as one wants, and that last bit of hydrogen and oxygen will not recombine to release heat. You didn't like my explanation, so here's your chance. I think you're already handicapped because you believe that all energy winds up as heat (in this case the chemical potential of the hydrogen and oxygen). So I'll be entertained to see how you handle it. S B H arris 04:32, 22 August 2006 (UTC)
Saying that heat is an example of the form to which other forms of energy are converted does not amount to saying "all energy winds up as heat" Charlie 05:36, 22 August 2006 (UTC)
By the way I'm still waiting for you to explain the hydrogen and oxygen forming from the water. How is the student trying to understand energy, to understand the role of energy in such processes? S B H arris 09:15, 22 August 2006 (UTC)
We have to get some basic concepts of entropy into this thing, because otherwise there's NO explaining why energy transforms at all! If you don't do that, this whole article becomes purely descriptive, like talking about ballistic paths without mentioning gravity. Golly, stuff just does stuff!
And by the way, I'm not married to the word "transmutation," I was simply explaining how I happened to use it. If you like "transformation" better, feel free to use that. S B H arris 22:18, 22 August 2006 (UTC)
Has anyone noticed that "Energy in Natural Sciences" is taking up the entire page, while other uses of energy are curiously absent? It would be nice if we could get all these equations off the page and into another article, because this article occaisionally feels slightly too specific. I suggest that this article needs one or more of the following:
-- DavidHOzAu 10:01, 18 August 2006 (UTC)
This reaction, with a cite, has been added to the article by somebody else. Since it improves the quantitative aspect of the article enormously, and since it's a good statement of just WHERE the energy involved in making living protoplasm goes, including the the elements which are involved, I think it should stay. One editor is simply deleting it, saying it's irrelevant. May we have some votes on the issue to reach concensus? Meanwhile, it stays. If nobody else likes it, I'll abide by concensus view. Perhaps a shortened version is more appropriate. I am tired of one editor assuming he's in charge of this article. As noted, the material in question was NOT written by me, but I happen to like it. So that's two votes in favor of keeping. S B H arris 18:39, 21 August 2006 (UTC)
The equation you removed did have a reference, and here it is again, since you missed it the first time you removed it: [1]. In taking it out, you managed to remove 50% of the references of an already badly under-referenced article. Congrats! If you believe the equation obsolete, say why.
I do not automatically revert edits. I do tend to object when people delete quantitative material without putting anything of substance back in. The result tends to be very bland. This article, rapidly losing quantitative material and references, becomes increasingly bland. I'm amused that you seem to see yourself as the only "sane" person working on the topic of explanation of energy, but I assure you that you aren't. S B H arris 04:16, 22 August 2006 (UTC)
Propose this whole section be deleted as irrelevant and biased. Money is NOT clearly related to physics energy in any way which can be quantitated. Second, here is not the place to argue about whether or not denizens of a democracy "consent" to democratic actions taken by their system (including wars and taxes) by choosing to continue to live there and not immigrate to someplace else. Finally, whether you agree with the US attack on Iraq or not, that wasn't about Iraq's energy. It would have been far easier to take over Kuwait or Saudi Arabia. Nor is the US ever likely to see any large fraction of the money it spent on that war (hundreds of billions so far), in oil. Basically, this section is a bunch of nonsense which contains no physics. And what politics it contains is muddled. S B H arris 17:34, 17 September 2006 (UTC)
I have shortened this section to something less than the personal essay which occupied it. Lumos3 11:23, 21 September 2006 (UTC)
There's more to Energy than formulas. -- DavidH Oz Au 06:53, 25 September 2006 (UTC)
The following comments were embedded in the Politics section but were not written by me. Moving them here. Lumos3 11:48, 26 September 2006 (UTC)
I suggest the creation of page called Energy resources, similiar to Water resources, leaving the more elementry stuff here. We could place most of "energy in practice", and have a politics section and talk about conflict on that page. See also List of energy resources. - Shiftchange 06:20, 29 September 2006 (UTC)
Inside the http://en.wikipedia.org/wiki/Energy#Conservation_of_energy section of this article, the following paragraph can be found
"Despite being seemingly insignificant, this principle has profound impact on processes in our Universe. It results in the existence of virtual particles which carry momentum, exchange by which with real particles is responsible for creation of all known fundamental forces (more accurately known as fundamental interactions). Virtual photons (which are simply lowest quantum mechanical energy state of photons) are also responsible for spontaneous radiative decay of exited atomic and nuclear states, for the Casimir force, for Van der Vaals bond forces and some other observable phenomena."
There is a a problem with what it says next to "Virtual photons", in the parenthesis and after the parenthesis: to say "are also responsible for spontaneous radiactive decay... [etc]" gives the impression that they are actual particles, not theoretical (or "virtual") particles as the very article on them says they are. The sentence previous to "virtual photons" is entirely confusing too, presenting a clear oxymoron: "it results in the existence of virtual particles", if they are virtual they can't exist, if they exist, they are not virtual.
I suggest rewording that paragraph, I would do it myself but I'd run the risk of making it even more misleading. If it was up to myself, I would actually remove that paragraph entirely, it does little good by not being clear enough to be explanatory, and is instead prone to cause more than one confusion.
Anybody supporting or opposing removal of that paragraph please say so and explain why. thank you Pentalis 11:44, 5 October 2006 (UTC)
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | Archive 2 |
This is pretty much a ramble showing the sort of thing that might be included. I find that in conversation with smart non-physicsts, they light up when I can get the unifying reason for using the concept of energy across to them.
There might be better examples to include, a satellite launch lower bound is orders of magnitude lower than practice, maybe energy in oscillators (pendulum, LC etc) would be good.
What do you think?
A Noob's first wiki contribution. Sorry about the link out to a new page, I didn't spot the next section [+] until I came to this Talk area, too late at night to change it now. NeilUK 00:39, 11 January 2006 (UTC)
Sigh.... Terry King 23:25, 26 February 2006 (UTC)
My history of physics is a bit rusty, but if I remember correctly, didn't Huygens first suggest a way of quantifying kinetic energy (albeit not knowing it was energy)? As I recall, he felt the need to introduce a new scalar quantity for mechanics. And then didn't Young find that work equals the change in energy? I felt compelled to suggest this, as the history section is a bit nebulous when it comes to the history of the topic before thermodynamics. Gershwinrb 07:36, 27 February 2006 (UTC)
this link in the bottom of the page:
What is that? it's a page full of ads with a very doubtful photo of what seems a spot on the lens of the camera and claims to be an "energy ball"
It's obviously a marketing trick. I think it should be removed right away. I don't do it myself cause i'm just a newbie, who just happened to reafd the article, and i leave it to discussion.
Apologies to all the scholars; this is a question from the masses...
The initial definition of energy appears to be a description of how matter behaves; not a definition of energy in its own, intrinsic nature. If I accept this definition; then energy has no individual existence - it is merely a concept of activity, a way to place a generic definition on the many ways in which matter can and does interact with itself.
Following on from this (pardon the macro-leaps in logic) if quantum particle physics claims that matter seems to be a result of the interaction of energy, confined into extremely small, relativistic volumes of space/time - this would suggest that energy is the action of matter; that (in itself) is the action of energy confined; that is matter in action; that is energy confined.......
See my dilemma?
Can Science actually explain to me: What is matter and what is energy, without referring one to the other? To explain away the actual definition of matter, by suggesting that it is some form of 'confined energy' - simply places the responsibility back on science to define energy. However, as energy seems to be defined as an action of matter -- you can see why I am dissatisfied with this definintion.
Please note; This is a genuine request for further explanation. I am not being silly. I am an individual who represents the readers/consumers of the Wikipedia experience. Although I appreciate the depth of knowledge being provided for me to use; I feel that there is both room for scholars to better explain their claims to the uninitiated AND use this forum to carry on their important work at the forefront of human knowledge. Sincerely, Greg Chalmers. cool!
---unfortunately, the only way to define energy is by mentioning matter. I know this may bug you but there is a reason: energy is relative. Think of it this way: from the frame of a person standing on the road, a truck has huge amounts of energy, this energy can only exist because the truck has mass. To say that anything relative to anything else has energy, that thing needs to have mass. In fact, Einstein noticed this relationship and found that mass itself is energy. The formula "E=mc(sq)" states that all matter is energy. In the same sense that time was found to be another dimension like space, space and time became the space-time, when mass was found to be another relative view of energy, mass and energy became mass-energy. Energy is nothing more than what matter is doing compared to what you are doing.
DEFINITION of ENERGY: "Energy is a fundamental property of a physical system and refers to its potential to maintain a system identity or structure and to influence changes (via forced interaction) with other system by imparting work (forced directional displacement) or heat (forced chaotic displacement/motion of a system molecular or related structures). Energy exists in many forms: electromagnetic (including light), electrical, magnetic, nuclear, chemical, thermal and mechanical (including kinetic, elastic, gravitational, and sound), where, for example, electro-mechanical energy may be kinetic or potential, while thermal energy represents overall potential and chaotic motion energy of molecules and/or related micro structure. "... Energy is the ‘‘building block’’ and fundamental property of matter and space and, thus, the fundamental property of existence. Energy exchanges or transfers are associated with all processes (or changes) and, thus, are indivisible from time." by M. Kostic: "Work, Power, and Energy" article in the Academic Press/Elsevier's Encyclopedia of Energy < http://www.kostic.niu.edu/energy>
See: [1] Also see: [2] and [3]
World Energy: At present, most of the World energy consumption is supplied by the fossil fuels (about 85%). However, the proven fossil fuel reserves are limited, and if continued to be used at the present rates, it is estimated that the coal (as used under current conditions) will be depleted in about 250 years, oil in 60, and natural gas in about 80 years. We have to keep in perspective that ‘proven reserves’ refers to the customary and economical ‘mining’ and utilization of fuels, but new reserves and more efficient technologies are being discovered, and make new fuel reserves economical. At present, a substantial amount of World electricity is obtained from nuclear and hydro energy, about 17% and 18%, respectively, and use of other renewable energy resources is increasing, namely geothermal, wind, biomass and solar, as well as development of alternative synthetic fuels, including development of hydrogen fuel cells, etc. It is worth noting that some countries produce almost all or most of their electricity from hydro energy (like Norway, Brazil, New Zealand, Austria and Switzerland), and France produces most of its electricity from nuclear fuel (76%). The nuclear fuel reserves are orders of magnitude higher than fossil fuels, and it does not contribute to CO2 and green-house pollution.
Furthermore, advances in energy conversion and utilization technologies and increase in efficiency, including computerized control and management, contribute to energy conservation, increase in safety, and reduction of related environmental pollution. Actually, per capita energy use in the U.S. and other developed countries is being reduced in recent years. However, the increase of World’s population and development of many underdeveloped and very populated countries, like China, India and others, will influence continuous increase of the World energy consumption.
Energy Future Outlook: The two things are certain: in not distant future (1) the world population and their living-standard expectations will substantially increase, and (2) fossil fuels’ economical reserves, particularly oil and natural gas, will substantially decrease. The difficulties that will face every nation and the world in meeting energy needs over the next several decades will be more challenging than what we anticipate now. The traditional solutions and approaches will not solve the global energy problem. New knowledge, new technology, and new living habits and expectations must be developed to address both the quantity of energy needed to increase the standard of living world-wide and to preserve and enhance the quality of our environment.
A probable scenario … in the wake of a short history of fossil fuels’ abundance and use (a bleep on a human history radar screen), the following energy future outlook is possible:
1. Creative adaptation and innovations, with change of societal and human habits and expectations (life could be happier after fossil fuels’ era)
2. Intelligent hi-tech, local and global energy management in wide sense (to reduce waste, improve efficiency and quality of environment and life)
3. Nuclear energy and re-electrification for most of stationary energy needs
4. Cogeneration and integration of power generation and new industry on global scale (to close the cycles at sources thus protecting environment and increasing efficiency)
5. Energy conservation and regeneration have unforeseen (higher order of magnitude) and large potentials, particularly in industry (also in transportation, commercial and residential sectors)
6. Renewable biomass and synthetic hydro-carbons for fossil fuel replacement (mobile energy, transportation, and chemicals)
7. Advanced energy storage (synthetic fuels, advanced batteries, hydrogen…)
8. Redistributed solar-related and other renewable energies (to fill in the gap…)
However, the outlook for future energy needs is encouraging. There are many diverse and abundant energy sources with promising future potentials, so that mankind should be able to enhance its activities, standard and quality of living, by diversifying energy sources, and by improving energy conversion and utilization efficiencies, while at the same time increasing safety and reducing environmental pollution (by M. Kostic).
M. Kostic, Treatise with Reasoning Proof of the Second Law of Energy Degradation, Manuscript, Northern Illinois University, 2006.
M. Kostic, Treatise with Reasoning Proof of the First Law of Energy Conservation, Manuscript, Northern Illinois University, 2006.
"A new scientific truth does not, generally speaking, succeed because the opponents are convinced or declare themselves educated, however because they die and the new generations from the beginning learn about it as the truth." by Max Planck (+) [at: Electrons.html ]
M. Kostic, Energy: Global and Historical Background, Manuscript for Encyclopedia for Energy Engineering and Technology (B. L. Capehart, Editor)], Taylor & Francis/Dekker, 2006.
M. Kostic, Energy: Physics, Manuscript for Encyclopedia for Energy Engineering and Technology (B. L. Capehart, Editor)], Taylor & Francis/Dekker, 2006.
Kostic, M., Irreversibility and Reversible Heat Transfer: The Quest and Nature of Energy and Entropy, IMECE2004, ASME Proceedings, ASME, New York, 2004.(ppt)
Kostic, M., "Work, Power, and Energy," Encyclopedia of Energy (C.J. Cleveland, Editor-in-Chief), Volume 6, pp. 527-538, ISBN: 0-12-176480-X, Elsevier, 2004.
Proposal : | Energy (physics)/Archive 2 → Energy (Physics) |
Rationale : | At the moment the title is too general, and the article is tainted with off-topicness about emotional energy and human energy supply. |
Proposer : | User:DavidHOzAu |
I agree to the proposal, with a minor correction, let there be a general page, for example, that on action, with links to various pages dealing with specific contexts. Charlie 09:12, 18 April 2006 (UTC)
Please add * Support or * Oppose followed by a brief explanation, then sign your vote using "~~~~".
Interestingly, majority of voters also suggested creating some sort of disambiguation on the topic. As per WP:D#Primary topic, Energy (physics) will redirect to Energy, and the top of this article will contain a note about Energy (disambiguation). -- DavidHOzAu 11:16, 28 April 2006 (UTC)
I have created
Energy (disambiguation) as a simple redirect to the Energy category for the time being, as that contains virtually the same information. If one
edits that page, you will see some starter text there for the disambigation. It is in need of someone with more experience creating disambiguation pages to further expand the text that is there. I'd have a more sophisticated hack at the page myself, but it is almost bed o'clock where I live. --
DavidHOzAu
12:53, 28 April 2006 (UTC)
Get the details here. The beginning was too unweildy, so I cleaned it up to just a raw definition, moved the remaining content to a new section, and glued the paragraphs together to make it more readable. -- DavidHOzAu 13:27, 11 April 2006 (UTC)
I have been attempting some cleanup lately. I believe that any word is not a propriety of any community. Discussions, about this page are often biased in favour of reserving its usage in the context of physics. I would advocate, an inclusive and comprehensive discussion of the use of the word, as it is used in various contexts, physics, technology, economics and spiritualism. Wikipedia should not repeat what is available in any textbook of physics, it has a much wider readership and contributers should keep that in mind. Too often, topics get biased in favor of a particular community. Charlie 09:24, 18 April 2006 (UTC)
To mathematicians, engineers, physicists and scientists, the word "energy" has a strict and quantifiable definition. Mixing of the non-scientific and scientific definitions of the word is deprecated and leads to confusion. Despite this, the fact remains that the word Energy is often used in contexts that are not as specific as the natural sciences.
For example, in the context of economics, the term energy is used in discussions related to resources, such petroleum products and electric power generation that enable us to use machines.
In the context of psychology, sociology, politics etc., energy can be in in the form of emotional energy, embodied energy, and perhaps psychic energy.
In the context of colloquial language, that is in common speech, the word energy is used to describe the behaviour of individuals. This may be similar to the physical use of the term work (force x distance), although this form is in fact quite different. Energy can be used to describe someone with a vigorous, enterprising, hard working or ambitious drive, or to describe someone’s physical and mental capacity when applied to a particular activity, or to describe someone with an vivid imagination implying vitality and intensity of expression. Similarly, The term "energy" is widely used in a spiritual or non-scientific way that cannot be quantified or even defined. The term energy, in such contexts, is used in traditional and New age mysticism and in fields such as parapsychology, acupuncture, IRECA method and reiki, prana anf yoga. Paranormal researchers will often refer to " psychokinetic energy" when attempting to explain paranormal phenomena or the concept of a spirit or soul. These forms of 'so called' energy are not quantifiable and are therefore unacceptable to the scientific community.
In traditional Chinese culture, energy is referred to as Qi.
Also, In my opinion, physical energy is the most common meaning when people think of energy, the article should focus on that -- Sullevon 17:40, 29 April 2006 (UTC)
There was a hidden comment at the top of the article that removing the link to Energy (disambiguation) was vandalism. However, that page is now a redirect to Category:Energy. Also, there is no meaning of the word "energy" which is not covered by the article. So, I think I'm removing it for good reason. -- Beland 01:49, 7 May 2006 (UTC)
Please see WP:DAB. The disambiguation is going to be there eventually, especially when someone fixes up Energy (disambiguation) sot that it is not a redirect and looks like the Rome (disambiguation) page. Better get used to it now. -- DavidHOzAu 05:59, 7 May 2006 (UTC)
As Energy (disambiguation), thanks to me. -- DavidHOzAu 07:12, 7 May 2006 (UTC)
I like the disambiguation page but it should be here under the main Energy article and this article sould be under Energy(physics). An encyclopedia should educate a reader to all uses not direct them into on particlar use. The current arrangement is a kind of POV pushing. Lumos3 08:16, 18 May 2006 (UTC)
Where should this equation go:
Where P=Power and t=Time? Isn't kind of crucial in showing how electrical and kinetic energy can be connected?-- The i kiro id ( talk)( Help Me Improve) 03:22, 19 May 2006 (UTC)
So should I add it in under something like "Electrical energy?"-- The i kiro id ( talk)( Help Me Improve) 20:49, 19 May 2006 (UTC)
from an inexperienced wikipedia user - under the heading Work, its stated that F=-mg. Now this is incorrect because the vector quantities F (gravitational force) and g act in the same direction. If down is taken as the negative direction then g=-g, F=mg and F=-mg. Right?
I am not sure about the context, but Acceleration has "speed change" and "direction", and is a vector in and of itself. It is convention that g always points to the local gravity sink, so I would think that the article best be changed to reflect convention. -- DavidHOzAu 06:03, 5 June 2006 (UTC)
This article was nominated for inclusion into the Version 0.5 release of Wikipedia, but it was failed due to a complete lack of references. Tito xd( ?!? - help us) 05:55, 31 May 2006 (UTC)
Consider an ideal monatomic gas in a container. If it is allowed to do (adiabatic) work on a piston (ie, it is transfered out of the system as work), the gas cools (loses thermal energy) by exactly the amount of work done on the piston. This does not represent an example of previous potential energy storage in the gas, since all energy transfered to the piston has come out of KINETIC energy of the gas molecules. No potential energy is involved at all, and the whole process only proceeds spontaneously because the amount of entropy created in expansion, is equal or more than the amount of entropy destroyed when the heat is destroyed to become work.
This process can be reversed, but not spontaneously. Work can be done to push the piston back in to compress the gas adiabatically, and in that case the work appears as heat (which again increases entropy over all). But again it's all kinetic energy (monatomic ideal case) and no potential is involved.
You'd think that rubber as in a rubber band would be a good example of potential energy due to intramolecular forces in the band. For a metal spring this is approximately true, but for a rubber band, it's not. Rubber acts very much like an ideal gas, evolving heat at about equivalent to work done on it, and absorbing heat with work that it does. Thus, no work is ever stored as potential or released from potential, unless you cause the heat to remain in the rubber and count the 50% of heat in solids which is potential. But even that isn't stored as potential if you isothermally cool the rubber as it is being stretched (say, with a flow of ideal gas), or isothermally warmed it as it is doing work. Which is to say that the rubber itself simply converts heat to work (and vice versa). If heat is supplied or conducted away isothermally, the rubber band stores no energy as potential at all, like the monatomic ideal gas.
Careful consideration of free energy will show that this can only be possible if the rubber has a lot of internal entropy change associated with stretching or de-stretching, such that the TΔS term is so large that all W can appear as Q. When rubber is stretched the isoprenoid polymers are pulled into alignment, and the methyl groups line up to look more like a crystal. This causes so much entropy decrease that all the work must appear as entropy-increasing heat, to make up for the TΔS. Thus, none can be stored as potential. The same happens on de-stretch.
All of this makes a nice illustration of why energy per se doesn't drive natural processes, and not even energy conversion to heat, if what is stored is "orderliness". A stretched rubber band can do work, and absorb heat to do it with. That's only possibile because a stretched rubber band is essentially a reservoir of stored LOW ENTROPY, not stored potential energy. Sbharris 22:17, 8 June 2006 (UTC)
The definition of energy, located at conservation of energy, is just plain wrong. It says that any transfer of energy results in a change in entropy. Entropy changes according to the Gibbs equation, which for a simple compressible system contains two terms, (1) work; and (2) the change in the internal energy. If these two terms are equal and opposite, the process is isentropic. Adiabatic expansion involving work being performed by the system on its surroundings will produce no change in entropy. -- PotomacFever 15:13, 28 June 2006 (UTC)
The description of the expanding universe found at Energy in Natural Sciences as it relates to entropy is not correct. Here's the passage:
I'd suggest we make these fixes to the above passage: (1) Since I'm not sure that "spontaneous diffusion of concentrated energy" is widely used, I'd suggest it would be better to describe the phenomenon as the expansion of the cosmic background radiation, which is the remnant of the matter-energy decoupling that occurred when the universe cooled to a temperature of 3000K. Since that time, the universe has been coextensive with a photon gas in frozen thermal equilibrium and whose wavelengths therefore fit a Planck distribution (see Planck distribution.) (2) Increased volume does not necessarily lead to increased entropy. For the expansion of the universe in particular, it would not be correct to say that entropy inceases owing to the "diffusion of concentrated energy into the volume available to it." (This last locution could be improved to say that the photon gas which comprises the Cosmic Background Radiation undergoes adiabatic expansion.) Adiabatic expansion would leave entropy unchanged.
I don't mean diffusion "powers" as in provides power for. I meant "drives". Most energy transformations in the universe are irreversible (entropy increases) and what drives them is their very irreversibility-- once they happen, they can't go back. We can say entropy increase drives these transformations, and that's the shorthand. If you want to say something more you need a brief description of entropy, or the kinds of things that entropy increase causes. Energy turns into heat and from that state, some of the energy must STAY as heat. Energy diffuses into volumes and some must then stay diffused. Radiation thermalizes and then is stuck as black body radiation. Heat flows from high to low temperatures (high to low energy concentrations) and then cannot flow back. And so on. It does no good to say that energy "transforms." WHY does it transform and why is it still transforming? I had something to say about that in the original version of the article (basically, it's because the big bang created volume faster than energy could equilbrate within it), but it got reverted. That's bad Wikipedia style-- the rule of Wikipedia is: Don't delete, improve. If you don't like my explanation and delete it, it's becoming on you to do better. Then I'll critique YOU. Energy transformation happens for a reason. You don't like my explanation, then have at it yourself. But simply blanking out my explanation and NOT providing your own substitute, is not much better than vandalism. I fully admit I may not explain it perfectly, but my explantion was certainly better than none, and none is what we presently have. S B H arris 21:08, 15 August 2006 (UTC)
Ireally do not understand the sentence "Energy also tends to be converted into heat over time, and part of this process is irreversible." Is energy different from heat. So far as I know heat is another word for thermal energy, a form of energy. Charlie
Were you talking about me when you said It appears some users believe that they can have an unchecked free run, that is they can make any inaccurate statement and get away with it.? What was inaccurate about what I said? I've said what was inaccurate about what you've said. It was simply wrong. Contact you? Here's your contact. You say it's "childish" to assert that heat is not a form of energy like any other form? Again, your adult explanation will be most amusing. But you owe us your best scientific explanation, not petulant reversions and deletions. And please leave out the unfactual "fixes" this time. S B H arris 05:00, 22 August 2006 (UTC)
Whatso ever editing I did is a result of many years of experience in science communication and not because I hold a PhD degree in science. 59.180.234.124 04:09, 19 August 2006 (UTC)
If one puts a small amount of perfectly pure water vapor into a container and waits, after a time a tiny amount of H2 and O2 will appear, and heat will be absorbed to form them, and the system will cool. WHY? Once the reader understands this, the reader will understand that reactions happen for reasons other than heat, and that not all energy winds up as heat. One can wait as long as one wants, and that last bit of hydrogen and oxygen will not recombine to release heat. You didn't like my explanation, so here's your chance. I think you're already handicapped because you believe that all energy winds up as heat (in this case the chemical potential of the hydrogen and oxygen). So I'll be entertained to see how you handle it. S B H arris 04:32, 22 August 2006 (UTC)
Saying that heat is an example of the form to which other forms of energy are converted does not amount to saying "all energy winds up as heat" Charlie 05:36, 22 August 2006 (UTC)
By the way I'm still waiting for you to explain the hydrogen and oxygen forming from the water. How is the student trying to understand energy, to understand the role of energy in such processes? S B H arris 09:15, 22 August 2006 (UTC)
We have to get some basic concepts of entropy into this thing, because otherwise there's NO explaining why energy transforms at all! If you don't do that, this whole article becomes purely descriptive, like talking about ballistic paths without mentioning gravity. Golly, stuff just does stuff!
And by the way, I'm not married to the word "transmutation," I was simply explaining how I happened to use it. If you like "transformation" better, feel free to use that. S B H arris 22:18, 22 August 2006 (UTC)
Has anyone noticed that "Energy in Natural Sciences" is taking up the entire page, while other uses of energy are curiously absent? It would be nice if we could get all these equations off the page and into another article, because this article occaisionally feels slightly too specific. I suggest that this article needs one or more of the following:
-- DavidHOzAu 10:01, 18 August 2006 (UTC)
This reaction, with a cite, has been added to the article by somebody else. Since it improves the quantitative aspect of the article enormously, and since it's a good statement of just WHERE the energy involved in making living protoplasm goes, including the the elements which are involved, I think it should stay. One editor is simply deleting it, saying it's irrelevant. May we have some votes on the issue to reach concensus? Meanwhile, it stays. If nobody else likes it, I'll abide by concensus view. Perhaps a shortened version is more appropriate. I am tired of one editor assuming he's in charge of this article. As noted, the material in question was NOT written by me, but I happen to like it. So that's two votes in favor of keeping. S B H arris 18:39, 21 August 2006 (UTC)
The equation you removed did have a reference, and here it is again, since you missed it the first time you removed it: [1]. In taking it out, you managed to remove 50% of the references of an already badly under-referenced article. Congrats! If you believe the equation obsolete, say why.
I do not automatically revert edits. I do tend to object when people delete quantitative material without putting anything of substance back in. The result tends to be very bland. This article, rapidly losing quantitative material and references, becomes increasingly bland. I'm amused that you seem to see yourself as the only "sane" person working on the topic of explanation of energy, but I assure you that you aren't. S B H arris 04:16, 22 August 2006 (UTC)
Propose this whole section be deleted as irrelevant and biased. Money is NOT clearly related to physics energy in any way which can be quantitated. Second, here is not the place to argue about whether or not denizens of a democracy "consent" to democratic actions taken by their system (including wars and taxes) by choosing to continue to live there and not immigrate to someplace else. Finally, whether you agree with the US attack on Iraq or not, that wasn't about Iraq's energy. It would have been far easier to take over Kuwait or Saudi Arabia. Nor is the US ever likely to see any large fraction of the money it spent on that war (hundreds of billions so far), in oil. Basically, this section is a bunch of nonsense which contains no physics. And what politics it contains is muddled. S B H arris 17:34, 17 September 2006 (UTC)
I have shortened this section to something less than the personal essay which occupied it. Lumos3 11:23, 21 September 2006 (UTC)
There's more to Energy than formulas. -- DavidH Oz Au 06:53, 25 September 2006 (UTC)
The following comments were embedded in the Politics section but were not written by me. Moving them here. Lumos3 11:48, 26 September 2006 (UTC)
I suggest the creation of page called Energy resources, similiar to Water resources, leaving the more elementry stuff here. We could place most of "energy in practice", and have a politics section and talk about conflict on that page. See also List of energy resources. - Shiftchange 06:20, 29 September 2006 (UTC)
Inside the http://en.wikipedia.org/wiki/Energy#Conservation_of_energy section of this article, the following paragraph can be found
"Despite being seemingly insignificant, this principle has profound impact on processes in our Universe. It results in the existence of virtual particles which carry momentum, exchange by which with real particles is responsible for creation of all known fundamental forces (more accurately known as fundamental interactions). Virtual photons (which are simply lowest quantum mechanical energy state of photons) are also responsible for spontaneous radiative decay of exited atomic and nuclear states, for the Casimir force, for Van der Vaals bond forces and some other observable phenomena."
There is a a problem with what it says next to "Virtual photons", in the parenthesis and after the parenthesis: to say "are also responsible for spontaneous radiactive decay... [etc]" gives the impression that they are actual particles, not theoretical (or "virtual") particles as the very article on them says they are. The sentence previous to "virtual photons" is entirely confusing too, presenting a clear oxymoron: "it results in the existence of virtual particles", if they are virtual they can't exist, if they exist, they are not virtual.
I suggest rewording that paragraph, I would do it myself but I'd run the risk of making it even more misleading. If it was up to myself, I would actually remove that paragraph entirely, it does little good by not being clear enough to be explanatory, and is instead prone to cause more than one confusion.
Anybody supporting or opposing removal of that paragraph please say so and explain why. thank you Pentalis 11:44, 5 October 2006 (UTC)