• #1
russ_watters
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Main Question or Discussion Point

Authorship Contributions From: Anorlunda
You may want to believe the article you read, or the video you saw, or you may be very proud of your PMM invention.   It can be very difficult to analyze what is inside the box to find the flaw. Maybe we can’t find it. Maybe nobody can find it.  If we can’t find the flaw, does that mean it will work? No, it does not. If you want to understand why, read this article.
The PF guidelines explicitly list Perpetual Motion and Free Energy as forbidden topics.  Why? They are are certainly popular topics. Almost every day we get new posts about articles that people read elsewhere, or from creative inventors.
The short answer is that a PMM would violate either conservation of energy, the 2nd law of thermodynamics, or both.   To a scientist or engineer, that is enough. Case closed, thread closed. But that may sound insufficient, dismissive, or even rude to the posters.  So a...
Continue reading...
 
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Answers and Replies

  • #2
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Very nice article.
Having been occasionally engaged by two patent attorney friends to provide guidance to would-be inventors, the advice for the "iconoclastic" PMM purveyor to try to design/build a working prototype was absolutely the best method to rationalize their enthusiasm. Surprisingly often it was the only way to keep them from squandering a boatload.
 
  • #3
Bandersnatch
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Thanks for this. I was just thinking how we could use a more thorough explanation for this particular forum policy, since the Guidelines are rather skimpy in this respect.

It's comprehensive, to the point, and not condescending.

Now, if we could have this as a link in the Guidelines instead of (or in addition to) the wikipedia and skepdic links...
 
  • #4
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  • #5
Klystron
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Excellent essay. Asking for a prototype also helps distinguish between inventors and outright scoundrels.

I remember a quasi-religious cult figure asking members to send gold objects to cult headquarters in order to substantiate a "Golden Pyramid". Since pyramids are "proven" energy sources, imagine the energy once the master coats the pyramid with gold. When asked to measure this energy increase, the master sorrowfully relates that the skeptic's negative energy flow creates interference. How much gold actually makes it to the pyramid requires a different measurement.
 
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  • #6
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First nice article. Great you mentioned Noether's Theorem which for me really says it all.

Thanks
Bill
 
  • #7
atyy
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But aren't we now discussing PMMs :oldconfused: o0)
 
  • #8
Ibix
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Asking for a prototype also helps distinguish between inventors and outright scoundrels.
Worth noting that a man called Joseph Papp built a "perpetual motion machine". Feynman was invited to see it and, knowing that it was a scam, disrupted the demo. The device exploded, killing one observer (see Feynman's write up, and some discussion supporting its authenticity). It's unlikely to happen with the genuine (if that's the right word) inventors because their devices just won't work, but scammers need their devices to "work" so they must contain some energy storage mechanism.
 
  • #9
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Interesting, and typical Feynman style. I'm fond of James Randi and his debunking methods. But as far as I know, Randi never turned his attention to PMMs.
 
  • #10
berkeman
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But aren't we now discussing PMMs :oldconfused: o0)
Yes, and everybody posting in this thread will be receiving an infraction, as soon as I get my PMM prototype working. Oh wait... o0)
 
  • #11
Ibix
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I'm fond of James Randi and his debunking methods. But as far as I know, Randi never turned his attention to PMMs.
I suspect it's rather a different skill set. While I rather suspect the psychology is similar (genuine believers, puzzle designers, and scammers exist in both areas), there's quite a lot of scientific knowledge needed to explain in detail where the flaw in a PMM design is. And even more to explain it in an engaging way - debunking PMMs is essentially the thrilling art of book-keeping, after all.
 
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  • #12
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there's quite a lot of scientific knowledge needed to explain in detail where the flaw in a PMM design is.
The article discusses exactly that. But the Feynman anecdote describes an entirely different approach to derail a demo of a fraudulent live prototype. Randi was skilled at figuring out how con men think, and from that how to derail their cons.

Actually, maybe in the article we should have distinguished between deliberate fraud, and innocent but naive "inventors."
 
  • #13
berkeman
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We get PMM posts in many guises here at the PF all the time. Great reply by @jrmichler in this current thread, for example...

Any piston that compresses isothermally must do so at low speed. A practical reality of low speed operation is that mechanical friction losses and leakage losses become a larger percentage of the total work. There is a speed that minimizes both adiabatic losses and mechanical friction losses, for the best compression efficiency. At that speed, the compression cylinder is "large", thus expensive. The most economical compression design trades off adiabatic losses, friction losses, capital cost, and operating cost to get minimum net present operating cost.

For an example of the reverse situation, search Atkinson cycle engine. The Wikipedia hit is a good place to start.

Then study some thermodynamics until you understand that you are trying to invent, if not a perpetual motion machine, a cycle better than the Carnot cycle (search that term also).

Do all of that until you can discuss your cycle using the correct equations, and calculating the efficiency relative to both isothermal and adiabatic compression. Do this while recognizing that your design cannot do perfect isothermal or adiabatic compression. Include pressure - temperature - time curves for your cycle, isothermal compression, and adiabatic compression. Discuss the conditions necessary to get isothermal and adiabatic compression, with calculations.

If you spend sufficient time studying the above, show us your work and we can help you proceed further.
 
  • #14
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What about those self running 3 phase dual permanent magnet self running motors? They are legit right? Permanent magnets contain all the energies?
 
  • #15
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What about those self running 3 phase dual permanent magnet self running motors? They are legit right? Permanent magnets contain all the energies?
I'm not sure what you mean, but no. PM PMMs are not OK, no pun intended.
 
  • #16
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Basically it was a joke about all those guys on youtube that are convinced permanent magnets contain magic, or somehow phase angle is connecting with the vacuum energy and that is why a 3 phase machine turning a DC motor with phase shift is apparently the secret to free energy. Mostly because magnets though I think.
 
  • #17
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What about those self running 3 phase dual permanent magnet self running motors? They are legit right? Permanent magnets contain all the energies?
Not if the permanents magnet remain magnets. Magnets can store energy, but are not a very efficient energy storage.
To have a genuine workable perpetuum mobile of first kind, you need to address squarely the Noether theorem. Not its validity, of course, but the symmetries that require conservation of energy.

Which asymmetries are needed to run a perpetuum mobile? If those asymmetries exist, can you observe them without actually using them to change energy?
And nonconservation of energy is by no means a sufficient requirement for a perpetuum mobile of first kind. Obviously a device capable of destroying but not creating energy is not a perpetuum mobile of first kind.
 
  • #18
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Having been occasionally engaged by two patent attorney friends....
Most of the time these were well-intentioned folks who were true believers. I felt like the damned Grinch as I tried to bring them down easy.
 
  • #19
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there's quite a lot of scientific knowledge needed to explain in detail where the flaw in a PMM design is
This is my failing with a persistent poster on another social site. I actually asked for hints on PF regarding his supposed internal combustion engine tech that runs on any fuel, at full torque, with no emissions...looks like magic, to me...but the thread was locked under the PMM rules :wink:

(I'm not disagreeing with the rule, BTW, and can see the rabbit holes it would take you down, because if this guy is typical, they don't engage, they just moan about how wonderful their idea is and how it's being "suppressed" by <some big company/industry>, and explain that they can't give you any details due to patent pending, or some such. We all have blinkers, but the self-deception required to genuinely believe you've invented a PMM seems a black hole of hubris.)
 
  • #20
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What about those self running 3 phase dual permanent magnet self running motors? They are legit right? Permanent magnets contain all the energies?
It is difficult to make a good PMM joke what keeps on running and won't get shot down :wink:
 
  • #21
HallsofIvy
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But it's alright to post questions about pink unicorns, isn't it?
 
  • #22
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It was Professor Sir George Porter who said that when he became a bit of science populariser he got lots of communications from people sending him their designs for PPMs. In the early days, he replied to them all pointing out why their machines wouldn't work but he had to give up doing this because it became too big of an imposition on his time.
 
  • #23
russ_watters
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But it's alright to post questions about pink unicorns, isn't it?
Yes, as long as they aren't invisible.
 
  • #24
russ_watters
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It was Professor Sir George Porter who said that when he became a bit of science populariser he got lots of communications from people sending him their designs for PPMs. In the early days, he replied to them all pointing out why their machines wouldn't work but he had to give up doing this because it became too big of an imposition on his time.
We had the same issue and resolution in the early days of PF.
 
  • #25
chemisttree
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Oh man! All my time has been wasted working on this Jupiter Toy Company Casimir Generator Turbine I guess....

Oh nevermind! Its been patented!
 

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