Is perpetual motion truly impossible?

AI Thread Summary
The discussion centers on the concept of perpetual motion and its feasibility, with references to physics textbooks that suggest it hasn't been observed yet. Contributors emphasize that any claims of perpetual motion violate the laws of thermodynamics, particularly the second law, which governs energy transfer. The distinction between free energy and perpetual motion is clarified, asserting that free energy derived from perpetual motion is impossible. Despite some claims of intuition and open-mindedness regarding perpetual motion, the consensus is that empirical data overwhelmingly supports its impossibility. Ultimately, discussions on perpetual motion are deemed inappropriate in this forum.
atal
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I found textbooks on physics (long time ago, when I was a student) where the authors said (paraphrase): "We do not assert that perpetual motion is impossible. It just hasn't been seen so far."
What do the mentors and contributors say about that statement?
(berkeman?)
 
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Think about the time it would take in terms of the age of the Solar System for a certain quantity of heat to be transferred from a cooler to a warmer body due to random thermal fluctuations.
 
It depends on the context of the statement. It could simply be talking About Newton's first law. But if it is talking about violations of the laws of thermo then it, or your recollection, is incorrect.

Edit: btw, the terms free energy and perpetual motion are not necessarily interchangeable. Free energy, if by which you mean due to perpetual motion, is impossible.
 
Thank you for your contributions.
Yes, it was about the second law; and it was in a book on thermodynamics.
And yes, I do refer to free energy as resulting from perpetual motion.
Not only is my recollection accurate, but I managed to prove that those authors had good intuition and open minds.

The opposition to perpetual motion, and the resultant free energy, is rooted in the paradigms. One of them is the classification of the physical systems into open and closed,
Think about a system which is ambiguous, fuzzy, with respect to those definitions.
I did construct that system.
But to apply it in life would mean utter destruction (misused).


I posed the question only for one reason: to see where the minds are today, years after Thomas Kuhn has broken ground on the scientific paradigms ("The philosophy of the scientific revolution")
 
atal said:
The opposition to perpetual motion, and the resultant free energy, is rooted in the paradigms.

No, it's rooted in the data. One data point is that thousands, perhaps tens of thousands, of inventors have claimed to make a perpetual motion machine, and the number that have been shown to actually work is identically zero.

In any event perpetual motion discussions are not allowed on PF.
 
I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...
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