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→The Uncertainty principle doesn't invalidate Perpetual motion...
::: I think that the Second Law applies to large systems with many interacting particles or bodies and is some kind of statement about their statistical behavior and how easily that motion can be observed.
::: I think that the Second Law applies to large systems with many interacting particles or bodies and is some kind of statement about their statistical behavior and how easily that motion can be observed.
::: Imagine, say, an ideal, large, sealed box whose walls perfectly hard (do not flex or absorb energy), and imagine that it one ideal billiard ball. By an "ideal billiard ball" I mean, again, one that is perfectly hard and perfectly elastic. If you have a single billiard ball in the box and it is moving, I think it keeps bouncing off the walls and moves forever. After all, energy is conserved.
::: Imagine, say, an ideal, large, sealed box whose walls perfectly hard (do not flex or absorb energy), and imagine that it contains one ideal moving billiard ball. By an "ideal billiard ball" I mean, again, one that is perfectly hard and perfectly elastic. If you have a single billiard ball in the box and it is moving, I think it keeps bouncing off the walls and moves forever. After all, energy is conserved.
::: Now, suppose, instead, that you have twenty-one ideal billiard balls, twenty of them at the vertices of an icosahedron and one in the center, all connected to each other by ideal springs. The entire structure, which I'll call a "blob," resembles a '''non'''-ideal ball. Put one of these into the ideal box and set it in motion with a gentle and identical force on each of those billiard balls, so that they are not moving with respect to each other and the whole blob moves together.
::: Now, suppose, instead, that you have twenty-one ideal billiard balls, twenty of them at the vertices of an icosahedron and one in the center, all connected to each other by ideal springs. The entire structure, which I'll call a "blob," resembles a '''non'''-ideal ball. Put one of these into the ideal box and set it in motion with a gentle and identical force on each of those billiard balls, so that they are not moving with respect to each other and the whole blob moves together.
::: This relative motion represents kinetic energy that belongs to individual billard balls within the blob, not to the blob as a whole, so because of conservation of energy, the energy we can ascribe to the blob as a whole is going to decrease, and so is the average velocity of the blob.
::: This relative motion represents kinetic energy that belongs to individual billard balls within the blob, not to the blob as a whole, so because of conservation of energy, the energy we can ascribe to the blob as a whole is going to decrease, and so is the average velocity of the blob.
::: I '''think''' that what the Second Law is saying is that the way in which the blob hits the wall is essentially random, and that with each impact, statistically, more and more energy is going to end up in the form of billard balls oscillating with respect to each other within the blob, and less and less organized motion of the entire blob as a whole.
::: I '''think''' that what the Second Law is saying is that the way in which the blob hits the wall is essentially random, and that with each impact, statistically, more and more energy is going to end up in the form of billard balls oscillating with respect to each other within the blob, and less and less in the form of organized motion of the entire blob as a whole.
::: So that whereas the motion of the single billard ball "never stops," after a while the motion '''of the blob''' has stopped, and instead you just have a stationary blob with the billard balls within it oscillating on their springs.
::: So that whereas the motion of the single billard ball "never stops," after a while the motion '''of the blob''' has stopped, and instead you just have a stationary blob with the billard balls within it oscillating on their springs.
::: In other words, the behavior of the system has ''degraded'' from observable motion of the blob as a whole to less-observable relative motion of the billiard balls within the blob. The system is in a less organized or "heat-like" state.
::: In other words, the behavior of the system has ''degraded'' from observable motion of the blob as a whole to less-observable relative motion of the billiard balls within the blob. The system is in a less organized or "heat-like" state.
::: However, because in this case we're talking about fairly large particles and a fairly small number of them, it is clear that the system is still "in motion," just on a smaller scale, and since we posited that the box, the springs, and the billiard balls are all ideal (and don't absorb energy), by conservation of energy the blob also continues in motion forever.
::: However, because in this case we're talking about fairly large particles and a fairly small number of them, it is clear that the system is still "in motion," just on a smaller scale, and since we posited that the box, the springs, and the billiard balls are all ideal (and don't absorb energy), by conservation of energy the balls within the blob also continue in motion forever.
::: Now, we go one step further and still keep the idealized, closed system with vacuum and perfect walls, but instead of a billard ball we use a real rubber ball. What the Second Law says is that the mechanical energy of the bouncing ball, 1/2 mv<sup>2</sup> where we can measure the "velocity" of the ball as a whole, inevitably and statistically degrades into heat; the ball "loses energy" with each impact with the wall, the measurable v decreases, and eventually it comes as close to "stopping" as we like. Conservation of energy says energy hasn't really been lost; it's been transformed into heat energy. The ball is warmer than before, meaning the molecules within it are moving, and since we've defined the system to be closed, it won't cool down. '''It''' has stopped moving, but there is still '''motion.'''
::: Now, we go one step further and still keep the idealized, closed system with vacuum and perfect walls, but instead of a billard ball we use a real rubber ball. What the Second Law says is that the mechanical energy of the bouncing ball, 1/2 mv<sup>2</sup> where we can measure the "velocity" of the ball as a whole, inevitably and statistically degrades into heat; the ball "loses energy" with each impact with the wall, the measurable v decreases, and eventually it comes as close to "stopping" as we like. Conservation of energy says energy hasn't really been lost; it's been transformed into heat energy. The ball is warmer than before, meaning the molecules within it are moving, and since we've defined the system to be closed, it won't cool down. '''It''' has stopped moving, but there is still '''motion.'''
::: Probably the place where the Second Law comes into play is that it says that even if you have a perfectly idealized "closed system," within that system ''energy'' won't be lost, but nevertheless energy ''observable as macroscopic motion'' can still degrade into heat energy ''no longer observable as macroscopic motion.'' [[User:Dpbsmith|Dpbsmith]] 09:40, 5 January 2007 (EST)
::: Probably the place where the Second Law comes into play is that it says that even if you have a perfectly idealized "closed system," within that system ''energy'' won't be lost, but nevertheless energy ''observable as macroscopic motion'' can still degrade into heat energy ''no longer observable as macroscopic motion.'' [[User:Dpbsmith|Dpbsmith]] 09:40, 5 January 2007 (EST)
== The Uncertainty principle doesn't invalidate Perpetual motion... ==
The Heisenburg Uncertainty Principle applies to sub-atomic particles like electrons only, we cannot know where they are at any given time <s>because of Brownian motion</s>. It does not apply to anything that can be seen without the aid of an electron microscope. Also, entropy doesn't increase, and the Second Law of Thermodynamics merely states that the universe tends towards Entropy. Also, the lack of creation of energy would be the Law of Conservation of Energy, which is present in many parts of Physics beyond the First Law of Thermodynamics. Also, the Earth is not a perpetual motion machine, to argue that it is does not border, plunges headfirst into absurdity and ignorance. Finally, the Earth has been slowing at a rate of about 2.2 seconds every 100,000 years due to frictions, no one considers it a perpetual motion machine. [[User:JanSmuts|JanSmuts]] 16:26, 12 April 2012 (EDT)
:I don't think that Brownian motion affects sub-atomic particles. Brownian motion moves things like pollen and dust which are orders of magnitude greater.--[[User:DavidEdwards|DavidEdwards]] 16:44, 12 April 2012 (EDT)
::No, Brownian motion is associated with sub-atomic particles, but has to do with collisions at an observable level, rather than their placement in shells. It would appear we are both incorrect, my mistake. [[User:JanSmuts|JanSmuts]] 17:02, 12 April 2012 (EDT)
::::I'm sorry, but you remain totally confused about Brownian motion even after acknowledging your earlier error. Brownian motion was first described by the biologist Robert Brown around 1827. He was describing a microscopic phenomenon and not a molecular one and certainly not a sub-atomic one. If your understanding of basic terms is so faulty I am not surprised that your conclusions are bad.--[[User:DavidEdwards|DavidEdwards]] 10:11, 13 April 2012 (EDT)
:::Well, then, do you think a [[perpetual motion machine]] can exist and, if not, then why not?--[[User:Aschlafly|Andy Schlafly]] 17:36, 12 April 2012 (EDT)
::::Isn't friction usually the answer? --[[User:JeromeKJ|JeromeKJ]] 18:19, 12 April 2012 (EDT)
:::::Another appeal to [[hearsay]]? The question doesn't request more hearsay.--[[User:Aschlafly|Andy Schlafly]] 18:38, 12 April 2012 (EDT)
::::::Sorry, you'll have to explain that comment. --[[User:JeromeKJ|JeromeKJ]] 18:48, 12 April 2012 (EDT)
:::::::According to all known laws of physics, no, such a machine cannot exist. However, the proofs you have offered are quite misleading and examples of bad science to say the least. [[User:JanSmuts|JanSmuts]] 23:04, 12 April 2012 (EDT)
::::::::"no, such a machine cannot exist." Why? And in response to the prior comment above, I'm not asking what is "usually the answer" by others (i.e., [[hearsay]]). I'm asking for your opinion and explanation.--[[User:Aschlafly|Andy Schlafly]] 23:49, 12 April 2012 (EDT)
:::::::::Can I please point out that the 2nd Law, at present, does NOT have any consistent and/or accepted deep physical mechanism behind it involving quantum mechanics or whatever. It can be justified by the argument that systems will naturally move towards larger homogenous volumes in phase space, but the question of WHY we think the 2nd law is valid is still entirely open. The Uncertainty Principle as normally presented (i.e. the product of uncertainties between certain pairs of eigenvalues of observables - specifically, those that don't commute with each other) in no way has any time-asymmetry in it. The 2nd law DOES have time-asymmetry. There's no argument that you, I, or any of the most learned physicists in the world can currently make which directly attributes "entropy" to "quantum uncertainty". If you have one, with the mathematics to back it up, please submit it to Nature, and prepare for a trip to Stockholm... [[User:DanPW | Dan W]]
::::::::::I appreciate the flattering suggestion, but the [[Nobel Prize]] is never given to a [[conservative]] and/or anyone who has publicly criticized the [[Theory of Relativity]] or the [[Theory of Evolution]]. See, e.g., [[Robert Dicke]], [[Fred Hoyle]], [[Ronald Reagan]], etc.
::::::::::I agree that narrow interpretations of the Second Law are, well, limited in what they conclude. But a full view of the meaning of the Second Law does recognize that quantum uncertainty underlies it. Quantum uncertainty does have a time-asymmetry to it ... just as attempts at a perpetual motion machine do.--[[User:Aschlafly|Andy Schlafly]] 22:33, 5 May 2012 (EDT)
::::::::::Interesting; as I said before, if you indeed can demonstrate this, and were subsequently denied a Nobel prize for it, I may accept your opinion that the committee is biased against those with a conservative viewpoint. Please point me to a derivation / demonstration of the uncertainty principle (other than those I have come across in my career, which are based on the Fourier transform of a wavepacket, for example, and which are not inherently time asymmetric) to back up your claim. Alternatively, please point me towards evidence that all current holders of the Nobel prize are liberals. [[User:DanPW]]
:::::::::::High correlation, in the absence of another plausible explanation, suggests high likelihood of causation. Undeserving liberals, such as [[Obama]], have won the [[Nobel Prize]], while over-deserving [[conservatives]], such as [[Ronald Reagan]], have not. Also, over-deserving scientists who criticized the liberal-promoted [[Theory of Evolution]] or the [[Theory of Relativity]], such as [[Fred Hoyle]] and [[Robert Dicke]], were passed over for the prize.
:::::::::::As to the time asymmetry of [[quantum mechanics]], the uncertainty yields greater uncertainty over time, as in quantum tunneling.--[[User:Aschlafly|Andy Schlafly]] 17:47, 6 May 2012 (EDT)
::::::::::::As to your "argument" about quantum tunnelling, I see that since you clearly have absolutely no understanding of what these concepts actually mean, there's little point in arguing this anymore. For the record, though, quantum tunneling arises due to the non-zero amplitude of a wavefunction in a classically forbidden region of a potential. The uncertainty principle is not what "causes" tunneling, rather both tunneling and the uncertainty principle are consequences of the wave nature of the statefunction. As to the Nobel prize, 1) whether or not you agree with Obama winning it (I certainly do not think he should have!), the Nobel Peace prize should be separated from the scientific prizes since it's clearly actually something to do with politics, wheras the other prizes are not, save perhaps for economics. Also, the fact that the committee has sometimes missed out on giving deserved awards (e.g. Franklin, Burnell, Hoyle, not so convinced about Dicke but I do recognise he was a great scientist, particularly in the area of electronics), does not give you any evidence of a liberal bias. As far as I can see, no mention has ever been made to the politics of any of these people. Fred Hoyle might well have been a liberal, or a conservative, we have no idea. [[User: DanPW]]