Talk:Perpetual motion

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Is there a bot for detecting 'softening' words?[edit]

I've made a few edits to the Perpetual Motion article in the last couple of months, all of which have the same gist -- removing inappropriate 'softening' of statements, e.g.

That second one was particularly egregious, since the principle being discussed is the 2nd Law of Thermodynamics, so that sentence claims "Perfect conversion of energy is in principle possible, except that it violates the principle of energy conversion."

In ordinary use, those sorts of softening words are used to convey things like "a very long time" or "a very high degree of efficiency", but in an article about infinite time horizons and 100% efficiency, those same softening words obscure the fact that the meaning of the sentence is the reverse of what the softening seems to convey.

I think I've removed most examples of this, but it made me wonder if there are any automated tools to look for this particular use of words like "almost", "seemingly", "practically", "in principle" and flag them for review? cshirky (talk) 03:08, 13 March 2016 (UTC)

feel free to make the article talk nonsense[edit]

Perpetual motion refers to ordinary bodies such as wheels and cogs. It doesn't refer to things so small that one cannot see them individually. At the level of atoms, the notion of friction has disappeared. Feel free to make nonsense of the lead by not making that clear. The second sentence of the lead is also wrong. Perpetual motion of the second kind doesn't do work, it just keeps going. The laws of thermodynamics hardly apply to motions such as the orbiting of planets, because they are far from thermodynamic equilibrium, and gravity on large scales is not within the scope of established thermodynamics. And feel free to talk about grammar when you mean style.Chjoaygame (talk) 20:32, 18 March 2016 (UTC)

There are several editors involved here. I'll address my changes. First, the article does not appear to address very small (atomic) scale as being different, or the requirement that an object must be macroscopic and observable individually to be able to discuss them. Another editor tagged the scale requirement as {{cn}}, which is reasonable. Note that you removed that tag without providing reference, merely stating "ordinary language". Given that the article itself doesn't appear to address the issue at all, I removed it altogether because WP:LEAD advises "Apart from basic facts, significant information should not appear in the lead if it is not covered in the remainder of the article", and the scale restriction is not an obvious or basic and undisputable fact. Atomic collisions and other interactions and lots of zero-point-energy perpetual motion machine fantasies all do agree with perpetual motion in a closed system not happening even at atomic level (and it's easy to find some RS that agree [1]). It's true that friction isn't a useful concept to discuss at atomic level, but that is not the only mode energy dissipation discussed in the article. As to my "grammar" change, I did not think perpetual motion is an object or countable entity, so I removed the indefinite article. That's also in keeping with the rest of the article that discusses this as a concept rather than an event. DMacks (talk) 20:55, 18 March 2016 (UTC)
Perpetual motions were schemes for wanna-be practical devices, dreamed up before there was practical evidence for the reality of atoms. They were not philosophical speculations about the inner workings of atoms. The choice of the default meaning, whether it assumed the existence and relevance of atoms, or did not, is a matter for common sense and context. Scale universality is not an obvious or basic and indisputable fact. The article does not address the inner workings of atoms, and it is natural to assume it is not referring to them. I think Democritus didn't think of atoms as having internal planets like motions; that was Bohr's invention, I think. Today one might ask about electron orbits and whatnot, but that is an anachronistic sophistication. It seems clever, of course. There were many perpetual motion schemes.Chjoaygame (talk) 13:18, 10 May 2016 (UTC)Chjoaygame (talk) 14:05, 10 May 2016 (UTC)
  • I agree that the lead was nonsensical in claiming that perpetual motion was impossible altogether. All atoms above absolute zero vibrate incessantly; that's what heat is. It's better to leave out absolute claims which seem more likely to confuse than inform and so I have removed the offending sentence. Andrew D. (talk) 20:50, 15 March 2017 (UTC)
I agree with Chjoaygame's position, at least with regard to atomic motion; it certainly should not be included. The word "perpetual motion" was coined before the concepts of energy or thermal motion were understood; what it meant was macroscopic motion, useful motion, work. That is the current meaning of the term "perpetual motion" in physics: either energy from nothing, or (p. m. of the 3rd kind) macroscopic motion without friction or loss. The definition must be based on WP:reliable sources, and I don't see any that include atomic motion [2], [3], [4], [5] --ChetvornoTALK 03:23, 16 March 2017 (UTC)

What about atoms?[edit]

Specifically, electrons orbiting a nucleus. It's not a machine or anything artificial, but does their motion continue forever? Or at some point (theoretically) they reach maximum entropy, something causes them to stop. Can this mean something moving forever, rather than just a machine, an object moving through space will go forever, unless some other force acts on it, stops it. The snare (talk) 05:01, 10 May 2016 (UTC)

They don't "orbit" in anything close to the planetary sense of that word. Our article on atomic theory discusses the evolution of scientific understanding of the nature of electronic behavior near a nucleus. DMacks (talk) 05:17, 10 May 2016 (UTC)
it is known for at least 100 years that electrons do not rotate around nucleus and that is why Pauling developed the notion of orbitals, but even this notion is not properly understood by some (it is the positions in space that can be occupied by electron, but electron is just hanging in one position depending on distribution of electromagnetic forces between nuclei and him or within one nucleus between all electrons and parental nucleus) — Preceding unsigned comment added by 134.7.193.46 (talk) 06:15, 29 July 2016 (UTC)

My understanding: Yes the electrons are in "motion" (they have energy), with the electron appearing in different places every time that it is observed. One can take energy out the atom until it reaches its lowest energy state, whereupon no more energy can be taken out, but the electron, even in its lowest energy state, still has some energy. So, the ground-state atom is in "perpetual motion", but it is not a "machine" that can be used to accomplish some sort of work. Correct me if I'm wrong about this. Isambard Kingdom (talk) 12:57, 19 March 2017 (UTC)

Thermodynamics cover only the part of Physics[edit]

it deals only with motion of particles due to T (it is caused by combined action of gravitational and EM fields, but indirectly), but not with the motion which is attributed to direct field's action on a matter...in this way exists not only the eternal motion, but and the eternal engine (it is actually the obvious fact since if exist an eternal motion, then must be and work done by this motion - eternal work)...so laws of thermodynamics are governing not all physical processes, but only temperature cycles...however the 1st law of TD is not the law of TD but general law of everything, since it is states that nothing appears from nothing...and the 2nd law of TD is actually again the general law of physics directly derived from the first and governs the differences in energy sizes (the most energetically favorable is minimal energy rather than higher energy).

The first law of Thermodynamics is a consequence of the conservation of Energy. Which according to Noether's theorem, it boils down to the time translation symmetry of Physics' laws. So, no it isn't a general law that says that "nothing appears from nothing". The second law isn't derived from the first, and it has nothing to do with energy sizes, but with entropy; that is the quality of each energy quantity. Finally, both laws are very strong and can be found in all parts of Physics (big/small scales, fast/slow speeds). Mlliarm (talk) 22:17, 24 June 2017 (UTC)

Some eternal engines[edit]

1. https://en.wikipedia.org/wiki/Foucault_pendulum based engine will work as long as Earth will rotate since it is not a realm of TD. 2. Magnetic field based rotors, since you need only to align magnetic poles correctly in order to force some massive wheel to rotate forever (or as long as magnetic field will maintain its strength, i.e. as long as the particle possessing it will be present and not destructed). This type of engine would be truly eternal and working on its own without additional input. 3. Earth's magnetic field can be exploited too like in the case of gyroscope (it is purely gravitational effect, but it can be made to generate and magnetic field which interaction with Earth's magnetic field would be larger than the energy required to spin the wheel called rotor). 4. Synthesis of elements and consequent splitting (exactly like our Universe is working...and yes Universe is infinite in both: time and space), since it is subthermodynamical realm of particles. This one is truly eternal too, just hardly manageable due to the requirement of huge masses in order to work. — Preceding unsigned comment added by 134.7.193.46 (talk) 05:38, 29 July 2016 (UTC)

All wrong, I'm afraid. btw, "thermodynamics" in the more general sense is not solely about heat. It's about energy in general. And all evidence is that it absolutely is conserved, even in quantum-level interactions. Jeh (talk) 21:43, 14 March 2017 (UTC)

"Interesting" advert about 6 pages long published about 30 years ago in New Scientist[edit]

Around 30 years ago there was an interesting advert in New Scientist about a perpetual motion machine.

Someone believed he could build a perpetual motion machine, tried to publish it in all the usual journals (Nature etc), but naturally the editors of the journals refused to publish this. The guy got frustrated, and took out several pages of advertising space in New Scientist, where he described the principle in a lengthy "scientific paper". It was really heavy on maths, and I never understood it, but I know one of the assumptions made was that c is not a constant. He reckoned c changed depending on whether the earth was moving towards or away from the sun. He could measure that change, but nobody else could, as his equipment was more accurate. Somehow this was going to be exploited to make a perpetual motion machine.

He wrote that he believed he would have a perpetual motion machine built in about 5 years. Needless to say, we have long since past that time, and he not got it working.

I wonder if anyone recalls that advert, or has a copy of it? Drkirkby (talk) 19:58, 14 March 2017 (UTC)

A library near me has their back issues of New Scientist as bound volumes rather than electronic. Can you narrow down the timeframe any better? DMacks (talk) 21:06, 14 March 2017 (UTC)