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Inventors Perpetual Motion Machines, Free Energy
By Mary Bellis

The USPTO will not knowingly issue a patent for a perpetual motion machine and the American Physical Society states, "The American Physical Society deplores attempts to mislead and defraud the public based on claims of perpetual motion machines or sources of unlimited useful free energy, unsubstantiated by experimentally tested established physical principles." On a personal note, I am fascinated with this stuff.

Perpetual motion machines* (the latin term perpetuum mobile is not uncommon) are a class of hypothetical machines which would produce useful energy "from nowhere." The existence of a perpetual motion machine is generally accepted as being impossible according to current known laws of physics. In particular, perpetual motion machines would violate either the first or second laws of thermodynamics. Perpetual motion machines are divided into two subcategories, referred to as perpetual motion of the first kind and perpetual motion of the second kind. There is a chance that the accepted laws of physics are wrong, but a lot of evidence is needed to regeneralize these.

Physicists may try to test their knowledge of physics by proving, without using thermodynamics, that a proposed perpetual motion machine cannot work. Also, sometimes physicists will discover "apparent" perpetual motion in thought experiments. Such "paradoxes" expose misunderstandings of the meaning of accepted physical theories and are considered quite instructive.

Because the principles of thermodynamics are so well established, serious proposals for perpetual motion machines are met with disbelief on the part of physicists, which makes a discussion of the merits of the proposal difficult if not impossible.

Serious discussions of perpetual motion usually occur only when dealing with the topics of open systems, aether theories, free energy, and vacuum energy.


Many say that perpetual motion machines violate one or both of the following two laws of physics: the first law of thermodynamics and the second law of thermodynamics. The first law of thermodynamics is essentially a statement of conservation of energy. The second law has several statements, perhaps the most well known is that entropy, or disorder, always increases.

Machines which claim not to violate either of the two laws of thermodynamics but rather claim to generate energy from unconventional sources are sometimes referred to as perpetual motion machines, although they do not meet the standard criteria for the name.

Kinds of Violations

First Kind

A perpetual motion machine of the first kind is one which produces power without energy uptake. Such a machine would, once started, operate indefinitely. This is forbidden by the law of conservation of energy.

Note that this explicitly prohibits the existence of devices which produce more energy than their input energy, as they can trivially be converted to a perpetual motion machine of the first kind by diverting part of their output energy back to their input.

Note that heat engines with an 'efficiency' greater than one do not violate this rule: the 'efficiency' in this case is defined as the ratio of heat output to work input -- the total energy input (heat + work) is still equal to the total energy output (heat).

Second Kind

A perpetual motion machine of the second kind is one which converts heat completely into other forms of energy. Such a device would violate the second law of thermodynamics and would be viewed with great skepticism.

*licensed under the GNU Free Documentation License It uses material from the Wikipedia article "Perpetual motion"


Eric's History of Perpetual Motion Machines and Free Energy Machines
The history of pm machines and free energy machines.

Did the USPTO Miss a Few
Patents for forbidden machines that were granted i.e. patent No. 6,362,718 for a "Motionless Electromagnetic Generator". Also see "Selling the Free Lunch"

The Museum of Unworkable Devices
PM machine proposals are often dismissed by scientists in a manner that appears to the layperson as hasty rejection using dogmatic assertions that such machines are prohibited from working by the "laws of thermodynamics".

Perpetual Motion Machine Designs
Collected designs for perpetual motion machines. #1 A machine created by Professor R.P. Feynman.#2 An underwater spinning donut. #3 Perpetual motion machine. #4 Piston based machine.

Joe Newman's Free Energy Claims
For over 20 years Joe Newman (born, Joseph Westly Rogers)  has been promising to demonstrate a device that produces more free energy than it consumes.

Joe Newman's Official Page
Inventor Joseph Newman, is perhaps one of the most notorious inventors associated with pm machines and free energy claims.

Maxwell's Demon
A machine of this type, of great antiquity and fine pedigree, is Maxwell's Demon, the prodigy of James Clerk Maxwell, one of the biggest brains in nineteenth century science and the architect of the modern classical theory of electricity and magnetism. A perpetual motion machine of the second kind is one which manipulates energy with perfect efficiency, i.e. one for which no energy ever leaks away into "useless" heat.

Does PM Exist
What's The Difference Between Motion and Machine?
Professor Hibbert's Perpetual Motion Page
Rolling Ball Perpetual Motion Machines

Related Information
Flying Saucers

From Mary Bellis,
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