Relative Posted September 27, 2014 Posted September 27, 2014 My evidence I offer, the design and motion of the Universe.
ajb Posted September 27, 2014 Posted September 27, 2014 I think this is not evidence as we do not have energy conservation in an expanding Universe (we have local conservation laws though) and we definitely have entropy increasing. I am not even sure how we can really incorporate general relativity into classical statistical physics anyway.
Relative Posted September 27, 2014 Author Posted September 27, 2014 On 9/27/2014 at 10:00 AM, ajb said: I think this is not evidence as we do not have energy conservation in an expanding Universe (we have local conservation laws though) and we definitely have entropy increasing. I am not even sure how we can really incorporate general relativity into classical statistical physics anyway. Locally the Earth perpetual orbits the Sun does it not? ''never ending or changing. "deep caves in perpetual darkness" synonyms: everlasting, never-ending, eternal, permanent, unending, endless,without end, lasting, long-lasting, constant, abiding, enduring,perennial, timeless, ageless, deathless, undying, immortal; More . occurring repeatedly; so frequent as to seem endless and uninterrupted. "their perpetual money worries" synonyms: interminable, incessant, ceaseless, endless, without respite, relentless,unrelenting, persistent, frequent, continual, continuous, non-stop,never-ending, recurrent, repeated, unremitting, sustained, round-the-clock, habitual, chronic, unabating; informaleternal "Clara could recall her mother's perpetual nagging at her father"'' Light also is perpetual? having a constant V?
Strange Posted September 27, 2014 Posted September 27, 2014 It may be worth noting that the term "perpetual motion" is normally used to mean a machine that can run forever with no input of energy. And in some cases, allowing the production of energy. It is that meaning that is absolutely impossible. Whether the universe will continue forever is unknown.
Relative Posted September 27, 2014 Author Posted September 27, 2014 '' I am not even sure how we can really incorporate general relativity into classical statistical physics anyway.'' I do not understand sorry, I am and have learnt science has one, and not catergorized has classical or modern etc.
ajb Posted September 27, 2014 Posted September 27, 2014 It is more subtle than just continuing forever. The point is that this motion continues without an external source of energy, which would been needed to compensate for energy loss due to friction or whatever. This violates the laws of thermodynamics. Now, planets do (almost) no work and so do not violate thermodynamics. The orbits of planets are not classified as perpetual motion. There is a small amount of work done due to space not really being a vacuum and one would also expect some energy loss due to gravitational waves. So in reality, a planets orbit is not stable forever.
Relative Posted September 27, 2014 Author Posted September 27, 2014 On 9/27/2014 at 10:20 AM, Strange said: It may be worth noting that the term "perpetual motion" is normally used to mean a machine that can run forever with no input of energy. And in some cases, allowing the production of energy. It is that meaning that is absolutely impossible. Whether the universe will continue forever is unknown. Thank you, yes I am aware that it is defined mainly based on a machine, however if the concept is there universally , the concept can be mimicked,. It exists in the Universe, so it must exist in reality. I do have an idea that may just work, but that's another thread another time. Has far has we are concerned, the entire recorded time of human existence, the orbit of the sun been perpetual, the answer is yes, and has far has we are concerned, is perpetual, if it stops, we will not be there to see it. Can you agree that the orbit is perpetual? A solar system is also ? On 9/27/2014 at 10:27 AM, ajb said: It is more subtle than just continuing forever. The point is that this motion continues without an external source of energy, which would been needed to compensate for energy loss due to friction or whatever. This violates the laws of thermodynamics. Now, planets do (almost) no work and so do not violate thermodynamics. The orbits of planets are not classified as perpetual motion. There is a small amount of work done due to space not really being a vacuum and one would also expect some energy loss due to gravitational waves. So in reality, a planets orbit is not stable forever. Infinite is only has long has our existence. How can science say that planets are not in perpetual motion?, the dictionary definition that i posted states they are?
ajb Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:20 AM, Relative said: I do not understand sorry, I am and have learnt science has one, and not catergorized has classical or modern etc. The point is that conservation laws in general relativity are much more subtle than in special relativity. This is in part why I am not sure how one can bring the arguments of classical statistical mechanics to bare on the whole Universe. I mean, an expanding Universe does not violate the second law of thermodynamics, but we don't have a global notion of energy conservation. The metric of a an expanding universe depends on time and so what does energy conservation mean in here?
Relative Posted September 27, 2014 Author Posted September 27, 2014 And you are not considering internal source of energy, proton-proton chain etc.
ajb Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:29 AM, Relative said: How can science say that planets are not in perpetual motion?, the dictionary definition that i posted states they are? Forget the dictionary and look up what a physics book say on the subject. 1
Relative Posted September 27, 2014 Author Posted September 27, 2014 On 9/27/2014 at 10:31 AM, ajb said: The point is that conservation laws in general relativity are much more subtle than in special relativity. This is in part why I am not sure how one can bring the arguments of classical statistical mechanics to bare on the whole Universe. I mean, an expanding Universe does not violate the second law of thermodynamics, but we don't have a global notion of energy conservation. The metric of a an expanding universe depends on time and so what does energy conservation mean in here? I will answer you soon, need to refresh on energy conservation.
ajb Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:31 AM, Relative said: And you are not considering internal source of energy, proton-proton chain etc. This has little to do with the gravitational physics of orbits.
Strange Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:29 AM, Relative said: however if the concept is there universally , the concept can be mimicked There is no reason to think that it is a universal concept. For example, there is no concept of energy conservation for the whole universe so the question becomes meaningless. Quote Can you agree that the orbit is perpetual? A solar system is also ? Not necessarily. The orbit of the moon is continually changing do to the loss of energy due to tidal effects. There is, I assume, also a very tiny loss of energy due to gravitational waves. So I doubt an orbit is stable for all time. Quote How can science say that planets are not in perpetual motion?, the dictionary definition that i posted states they are I don't know if science does say that. All I said was that that is not what "perpetual motion" usually means. You would have to watch the solar system for an infinite time to answer the question!
Relative Posted September 27, 2014 Author Posted September 27, 2014 On 9/27/2014 at 10:32 AM, ajb said: Forget the dictionary and look up what a physics book say on the subject. ''Perpetual motion is motion that continues indefinitely without any external source of energy.'' The Sun has internal F, not external
Strange Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:35 AM, Relative said: ''Perpetual motion is motion that continues indefinitely without any external source of energy.'' The Sun has internal F, not external I assume you mean "internal E"? Anyway, the Sun's source of energy is finite. In a few billion years its reactions will end.
Relative Posted September 27, 2014 Author Posted September 27, 2014 (edited) On 9/27/2014 at 10:33 AM, ajb said: This has little to do with the gravitational physics of orbits. The internals of the Sun make the orbits do they not? The Sun rotates perpetual? Solar systems spiral perpetually? Unless you are saying there is forces acting upon our visual universe, from outside our visual universe? On 9/27/2014 at 10:38 AM, Strange said: I assume you mean "internal E"? Anyway, the Sun's source of energy is finite. In a few billion years its reactions will end.'' Relative-Yes E, and if it ends no one will be here to see any further, no future, so perpetual can only be seen has , has long as we live, humanity. Technically you could not make a machine because in time, the world will end and the machine would break anyway if you are talking infinite. Our existence is what matters, and technically to us the orbits are perpetual by definition, unless science is now saying the dictionary is wrong and making its own terms up, sound familiar? Edited September 27, 2014 by Relative
Strange Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:45 AM, Relative said: The internals of the Sun make the orbits do they not? Only the mass is relevant. Quote The Sun rotates perpetual? Yes, because of conservation of angular momentum. Quote Solar systems spiral perpetually? Maybe. (Although, if it was actually a "spiral" then the answer be no!)
ajb Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:35 AM, Relative said: ''Perpetual motion is motion that continues indefinitely without any external source of energy.'' This is correct. But like I said, the planets do (virtually) no work and so there is no problem here with perpetual motion at all.
Strange Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 10:09 AM, Relative said: Light also is perpetual? having a constant V? Photons that do not interact with anything will continue indefinitely; they will not decay spontaneously. (This has nothing to with their constant velocity. Well, indirectly I suppose. They have constant velocity because they are massless. That is also partly why there is no decay path [i think].)
Relative Posted September 27, 2014 Author Posted September 27, 2014 On 9/27/2014 at 10:58 AM, ajb said: This is correct. But like I said, the planets do (virtually) no work and so there is no problem here with perpetual motion at all. I think I let myself get confused now, ''A perpetual motion machine is a hypothetical machine that can do work indefinitely without an energy source'' So what external E source, makes the planets spin, and have an orbital path around the Sun?
Strange Posted September 27, 2014 Posted September 27, 2014 On 9/27/2014 at 11:11 AM, Relative said: So what external E source, makes the planets spin, and have an orbital path around the Sun? There is no external energy source required because they are not doing work.
Relative Posted September 27, 2014 Author Posted September 27, 2014 I have an idea of a machine that should in concept, be perpetual motion, however, the machine would harvest external energies , from the Universe, to make it work somehow. The motion would be none battery and continued, but according to science, this would not be perpetual? On 9/27/2014 at 11:13 AM, Strange said: There is no external energy source required because they are not doing work. Yes they are doing work, they are in motion, how can you define motion has not work. Every action has an opposite reaction,
ajb Posted September 27, 2014 Posted September 27, 2014 (edited) On 9/27/2014 at 11:11 AM, Relative said: So what external E source, makes the planets spin, and have an orbital path around the Sun? The rotation is due to conservation of angular momentum and the formation of the solar system. The gas and dust that collapsed to form the solar system must have been spinning itself. It is gravity that keeps the planets in orbit around the Sun, but we don't need an energy source as the planets are doing no work. Edited September 27, 2014 by ajb
Fuzzwood Posted September 27, 2014 Posted September 27, 2014 Here we go again. Posts upon posts explaining advanced physics from different angles while the basics are not yet understood... 1
Relative Posted September 27, 2014 Author Posted September 27, 2014 On 9/27/2014 at 10:33 AM, Relative said: I will answer you soon, need to refresh on energy conservation. On 9/27/2014 at 11:18 AM, ajb said: The rotation is due to conservation of angular momentum and the formation of the solar system. The gas and dust that collapsed to form the solar system must have been spinning itself. It is gravity that keeps the planets in orbit around the Sun, but we don't need an energy source as the planets are doing no work. The planets do work, opposite reaction to action,
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