Though several others have attempted to clarify the definition earlier in the thread it remains confused.
http://en.wikipedia.org/wiki/Perpetual_motion
perpetual motion
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Though several others have attempted to clarify the definition earlier in the thread it remains confused.
http://en.wikipedia.org/wiki/Perpetual_motion
So wikipedia and Stanford have it wrong?prometheus said:
I'm afraid your explanation doesn't even start to explain why, or even suggest what is wrong. Do you mean: "However, after the collision, the system, which now consists of two photons moving in non-parallel directions, also has a non-zero rest mass" is wrong, or do you mean "energy, in all of its forms, has mass" is wrong?
Why should anyone believe you instead of either source? Why aren't you wrong?
My language is not English.
For me in this case Wikipedia is a bit confusing.
It defines "perpetual motion" and then give the classification for "perpetual motion machine".
So I'm not sure if "perpetual motion" has the same meaning as "perpetual motion machine".
When you open that page on the left side lower section begins a list of languages that google can translate the page to. These work like links select one and click on it. Hopefully, a language better suited to you is available.
I know.
In my language there is only one term, namely the Latin: "Perpetuum Mobile".
O.K. I can see how that does not work. It does not really have the same meaning as intended in the Wiki article.
Basically in the context that most people in the science community would understand it, "perpetual motion machine" and thus "perpetual motion" get tied into the idea that you can make a device that once you get it going it will never stop, even while you are using it to do work.
It is kind of like saying, "I have discovered a battery that will never run out of power, even when the universe itself.., runs down.
It is like saying I have this bucket that I can fill once with water and then no matter how much of the water you take out it will always be full.
These are crude examples but I was trying to bridge the language gap, so you could understand what it sounds like you are saying to many others.
Hope that helps...
I do not understand exactly what it means:
If translated literally, then yes.
But "Perpetuum Mobile" does not translate. It is a well-defined notion.
The problem is probably not with the translation of "Perpetuum Mobile" to English, rather the translation of the English, "perpetual motion" to Latin.
The direct translation to the Latin, is not consistent with the context that "perpetual motion" has in English to physics. The direct translation is an inaccurate translation of the meaning in English.
A better direct translation of from Latin to English would be as I suggested, continuos or constant motion.
Perpetual motion, in English, has come to be associated with a number of scams Claiming things like a fuel that is self regenerating and engine that runs on air alone, that work can be done at no cost or ...
Say I have an electric motor that is really efficient 40%... and I connect it to a generator that is really efficient 40%... perpetual motion in western physics is like saying I can use the motor to drive a car down the road while it runs the generator that provides the electricity to run the motor. It is like saying that you can get more energy back from the motor and generator than you put in without consuming any other fuel.
It is like saying I have a gasoline engine that does not require a fuel tank because it runs without fuel.
It is like saying that work can be done without it costing any energy. Or that people don't need to eat as long as they just breath.
I know some of these are very far out there as examples but again I am trying to cross that language barrier, to get the essence across.
I don't understand why you give these explanations.
The question was simple.
Has the same meaning or not? :shrug:
(It remains the bewilderment from post #68.)
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I don't understand why you give these explanations.
The question was simple.
Has the same meaning or not? :shrug:
(It remains the bewilderment from post #68.)
Not exactly the same meaning but they are taken to imply the same thing. Very often in English if you use the term perpetual motion it is taken as if referring to a perpetual motion machine or a similar process.
I appologize for the long and apparently unnecessary explanations.
Thanks.
Motor Daddy
Valued Senior Member
I made it perfectly clear what I meant in post #51:
OnlyMe is just trying to squirm out of a direct reply to my question to him, because it leads him down a dead end.
I say again, there is no environment that an object is free of any external forces. If you think there is let's hear it.
OnlyMe is just trying to squirm out of a direct reply to my question to him, because it leads him down a dead end.
I say again, there is no environment that an object is free of any external forces. If you think there is let's hear it.
While in a literal sense the use of the word perpetual in the context of the phrase "perpetual motion" may be accurate, as expressed in the exchange between Emil and myself it is also loaded with a history that distorts the intended meaning.
It would seem that for the purposes of the below mentioned posts, unless the intent is to illicit misunderstanding, the intent would be as well if not better served by one of the following, "constant motion" or "continuos motion". Perhaps even including a further qualifier indicating a "uniform" aspect to the involved motion.
Continuing to insist on terminology that one knows will (once again) illicit, confusion and reaction, does not further any genuine disscussion.
While from the perspective of special relativity there can be no frame of reference from which one can assume that any object is in a state of "absolute rest", this in and of itself does not preclude the possibility that there exists some frame of reference within the universe where all external forces are balanced and have no net effect on an objects state of motion.
Paraphrasing Einstein, while one can imagine a volume of space where there is no electromagnetic field, potential or influence, one cannot imagine space without some gravitational influence. That said it is logical to assume that some where in the depths of space between galaxies the gravitational forces acting upon an object are balanced. The object's motion would then be influenced by no external force and thus governed by inertia alone.
This is not in conflict with SR as the object's motion while not influenced by an external force would still be relative.
For the most part, from my perspective participation in discussions on these forums is not one of attempt lying to convince anyone that I am right and they are wrong. Instead it is an exchange of ideas and perspectives. To that end when in post 63, Emil suggested that there might be some language barrier involved in understanding what I see as a loaded interpretation of the use of the phrase, "perpetual motion", we Emil and I discussed the issue over the corse of about 10 posts. It is of no real concern to me what or how anyone else believes the world to be. It is of some concern that when we communicate we understand how what we are saying is understood by others. I believe this was accomplished during that conversation.
I did not respond to your, (Motor Daddy) post and question for two reasons. One it seemed more like a challenge than reasoned communication. And second at the time I saw no constructive discussion of the larger context of your post demonstrated in the quoted portion of your post below. The difference in what it seems to me your are saying and how I understand things to be is to great to be dealt with in an easy manner and I have not had the impression that the discussion would be an exchange of ideas as much as a continued challenge of ideas.
Again, my only objective in these forums is an exchange of ideas and perspective. I am in no way married to convincing anyone of anything beyond clear communication of intent and meaning.
I believe I address my view on this in my leading comments.
Here I think that once again the use of the word "perpetual" can be misinterpreted and what I believe the intent to be would be better served by the use of "constant" and/or "continuos", with a possible qualifier of "uniform".
It would seem that for the purposes of the below mentioned posts, unless the intent is to illicit misunderstanding, the intent would be as well if not better served by one of the following, "constant motion" or "continuos motion". Perhaps even including a further qualifier indicating a "uniform" aspect to the involved motion.
Continuing to insist on terminology that one knows will (once again) illicit, confusion and reaction, does not further any genuine disscussion.
While from the perspective of special relativity there can be no frame of reference from which one can assume that any object is in a state of "absolute rest", this in and of itself does not preclude the possibility that there exists some frame of reference within the universe where all external forces are balanced and have no net effect on an objects state of motion.
Paraphrasing Einstein, while one can imagine a volume of space where there is no electromagnetic field, potential or influence, one cannot imagine space without some gravitational influence. That said it is logical to assume that some where in the depths of space between galaxies the gravitational forces acting upon an object are balanced. The object's motion would then be influenced by no external force and thus governed by inertia alone.
This is not in conflict with SR as the object's motion while not influenced by an external force would still be relative.
For the most part, from my perspective participation in discussions on these forums is not one of attempt lying to convince anyone that I am right and they are wrong. Instead it is an exchange of ideas and perspectives. To that end when in post 63, Emil suggested that there might be some language barrier involved in understanding what I see as a loaded interpretation of the use of the phrase, "perpetual motion", we Emil and I discussed the issue over the corse of about 10 posts. It is of no real concern to me what or how anyone else believes the world to be. It is of some concern that when we communicate we understand how what we are saying is understood by others. I believe this was accomplished during that conversation.
I did not respond to your, (Motor Daddy) post and question for two reasons. One it seemed more like a challenge than reasoned communication. And second at the time I saw no constructive discussion of the larger context of your post demonstrated in the quoted portion of your post below. The difference in what it seems to me your are saying and how I understand things to be is to great to be dealt with in an easy manner and I have not had the impression that the discussion would be an exchange of ideas as much as a continued challenge of ideas.
Again, my only objective in these forums is an exchange of ideas and perspective. I am in no way married to convincing anyone of anything beyond clear communication of intent and meaning.
I believe I address my view on this in my leading comments.
Again with the over-thinking...Pick a frame. *Virtually all existing objects relative to that frame are in perpetual motion. *
Here I think that once again the use of the word "perpetual" can be misinterpreted and what I believe the intent to be would be better served by the use of "constant" and/or "continuos", with a possible qualifier of "uniform".
Fine, then throw a rock from Earth with sufficient escape velocity and direction such that it travels in uniform motion (at least at the limit, sufficiently distant from gravity wells), forever.OnlyMe said:
Newton's First Law came before Thermodynamic's Second.
It's really the "extracting useful work" from any sort of perpetual motion where you will encounter problems.I googled "energy has mass", and it seems the jury is still out. Quite a few people seem to be confused about what E = mc[sup]2[/sup] really means.
But anyways, here are two quotes from supposedly reliable sources (and there are plenty of hits from that google search that seem to agree with Einstein's idea, and so, wikipedia isn't wrong)
So, it seems that Einstein's equation might NOT be that well understood by the general community. Note that the Stanford Library reference discusses some of the ontological problems the equation seems to have, these appear to be related to the difference between a Newtonian concept of mass, and a relativistic concept of the same thing. But I'm winging it here.
I note also that the wikipedia article says:
So, um, what the . . .?
But anyways, here are two quotes from supposedly reliable sources (and there are plenty of hits from that google search that seem to agree with Einstein's idea, and so, wikipedia isn't wrong)
--cavendishscience.org
--Martinus J Veltman
So, it seems that Einstein's equation might NOT be that well understood by the general community. Note that the Stanford Library reference discusses some of the ontological problems the equation seems to have, these appear to be related to the difference between a Newtonian concept of mass, and a relativistic concept of the same thing. But I'm winging it here.
I note also that the wikipedia article says:
So, um, what the . . .?
onemancannon
Registered Member
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OnlyMe makes a good point that 'perpetual motion' is a term that has a very distinct connotation in English. It is generally a reference to perpetual motion machines, and almost always a reference to the large and overbearing concept that it is a physical impossibility, which it technically is.
However, there are respectable scientists who believe that over unity devices are possible - and at least one of them has been awarded a Nobel prize. There are in fact people working to develop the technology to provide a real power source, as I have recently showed with my post on athermal lasers. Some guy in the Netherlands was trying to make tiny antennas that would harness infrared radiation, but I haven't seen much about this in a few years.
However, there are respectable scientists who believe that over unity devices are possible - and at least one of them has been awarded a Nobel prize. There are in fact people working to develop the technology to provide a real power source, as I have recently showed with my post on athermal lasers. Some guy in the Netherlands was trying to make tiny antennas that would harness infrared radiation, but I haven't seen much about this in a few years.