Tom Booth

Here is something else interesting. Quite a long time ago, possibly living in Arizona or California or where exactly I cant remember but I saw what I believe was a local news broadcast of some guys in a garage who were blowing air through a T shaped tube with a shop air compressor. The thing appeared to be nothing more than some copper plumbing pipe but they were blowing air into the bottom of the T and naturally the air was coming out the other two legs of the T but the remarkable thing was that bitter cold freezing air was coming out one side and burning hot air was coming out the other. It has been a long time since then but I have finally, very recently, (thanks to the internet which didn't exist back in those days) located information regarding what I saw in that brief newscast so many years ago. One name for it is "Wirbelrohr" also "Hilsch Vortex Tube" and is sometimes also referred to by some as "Maxwell's demon". There are quite a few DIY guides or instructions, diagrams etc. to build your own. Not very much to it really but apparently it works. Here is one site with rather detailed diagrams: http://www.visi.com/~darus/hilsch/index.html Of course, you need compressed air. If you had an air compressor that could run from a temperature differential than here is another very simple way to get the temperature differential to run the air compressor with no additional moving parts! According to some reports it seems that it is possible to get the heating and cooling effect by simply blowing through the thing by mouth, though you would need pretty good lungs apparently. There are also commercial versions being sold. I'm currently working on putting together a slightly bigger test model of the "Ice Powered" Air compressor. Wooden Body to reduce heat loss by conduction Lighter weight Styrofoam Displacer Larger copper heat conducting plates.

I find this very interesting. In particular "Further, the energy that fuels you ultimately comes from the sun, so you don't have a closed system." What I am really interested in in regard to all this is how it might apply to a particular design for a Heat Engine of my own invention. I've been told repeatedly by various persons over the years that it cannot work because it would be a violation of the Second Law of Thermodynamics. One of my arguments to the contrary was that the engine is not a closed system and that the fuel to run the engine is ultimately heat from the sun. This seems to be the same as the argument you are putting forth here that Life does not violate the Second Law of Thermodynamics for the same reasons I came to find out recently that Tesla conceived a similar engine that he believed could operate on ambient heat he called a "Self acting engine" - able to run on indirect heat from the sun stored in the medium. He seems to be saying that it would be possible under some special circumstances which he describes quite clearly IMO, to extract heat from the atmosphere (heat ultimately coming from the sun) and convert that heat into a different form of energy so as to leave behind a "Sink" or "Cold Hole" for additional heat energy to flow into and thus be able to extract additional energy from that heat. The energy gained could then be used to expel any residual heat not converted so that the "cold hole" could be maintained indefinitely - so long as at least some of the incoming heat continued to be converted to some other form of energy. It seems to me that my engine design is conceptually identical to what Tesla describes. My question is, regardless of any particular design, conceptually, is Tesla's (or my) idea "a violation of the second law of thermodynamics" ? I posted excerpts from Tesla's article here: http://www.scienceforums.net/topic/46143-stirling-turbine/page__view__findpost__p__619315 There are also some diagrams and a GIF animation providing a conceptual "working model" of the engine. I'm sure some posting here have already viewed this, but I would be interested in getting any opinions regarding this 2nd Law question.

OK,... if you say so. Would you agree that at one time "animate" objects (life forms) were conceived to be excluded as obvious exceptions ? If so, at what time or place was there an official change or pronouncement that "animate" life forms would be included in the formulation ? Or no longer excluded rather ? It seems a great deal about the general theory of thermodynamics involves the imagination and includes what seem to me to be arbitrary definitions with no clearly fixed boundaries. For example: "isolated system" in particular I've been having some trouble with. Granted, the sun was shining. I had eaten something previously, I was breathing air, etc. If a so called "isolated system" is found to have negative entropy, the argument goes that you just move the boundary until you come up with the right numbers to satisfy the formula. (Or imagine that you have.) The definitions of "System", "open system", "isolated system" don't seem to have any governing rules. It is impossible to win an argument against the second law of thermodynamics not because it is true but because the game is fixed. Heads I win, Tails you lose. This kind of moving boundary argument is something I've seen repeatedly in discussions of the topic practically from its first inception. It seems to me that this is changing the definitions to satisfy what amounts to a belief, I think. If the numbers don't square right you can just redefine your "isolated system". Move the boundary line. So, lets go ahead and do that. Now we include my "lunch" or consumption of "fuel". At this point we have introduced another case of negative entropy. Metabolism. And another. Since my food consisted of various complex organic compounds we would have to include the processes involved in growing plants. Inert molecules (dirt) combining with air and sunshine to assemble themselves into the highly complex cellular formations to be found in the tomato on my sandwich for example. We may have shifted the problem further away from the immediate area but I don't see how this solves the "problem" of life in all its varied forms exhibiting "negative entropy" or creating order out of disorder. We can continue moving the boundary. Redefining what constitutes our "closed system" until we reach the ends of the universe, but by this time I think we have left reality and gone off into literal flights of the imagination. Can it be, or has it ever been "proven" that "the universe" is an "isolated system" ? If the ashes that constitute the inert remains of a human being are scattered around my wood pile and "fuel"; (air, sunshine and a BLT sandwich) is added to the mix, does the pile of wood that was dumped out of a truck then assemble itself into stacks ? But this is all getting rather philosophical and pretty far removed from the subject of heat I think. BTW, I benefited from the exercise. Breathed fresh air and was considerably invigorated by the wood stacking. So how did my entropy increase during the process ? Also, in regard to my lunch. It went from a state of relative disorder as a sandwich to a state of considerably greater complexity as part of my blood and bones, muscles, general cellular structure, mitochondria, ribosomes, lysosomes, enzymes, DNA etc. so how did the entropy or state of disorder of the sandwich increase ?

Well, There are a few things posted earlier I might respond to at some other time but I have a thought on this at the moment so I'll post it before going off to work. (to stack more firewood). My point in my earlier posts made last night was that Life seems to violate entropy. (i.e. 2nd Law.) True, the firewood did not stack itself. A life form stacked the firewood. Your statement above it seems to me, reflects an unconscious assumption that this "Life Form" is excluded from the "system" under consideration. This goes all the way back to the earliest formulations of the "Laws" of thermodynamics. If as suggested earlier I took a nap on the ground, taking the "Tom, Yard, Firewood" system as a whole and viewing it strictly in terms of a collection of inanimate atoms. (i.e. making no pre-judgement in regard to the definition of "animate" or "inanimate") There was an apparent "spontaneous" ordering performed by the collection of atoms that compose the Tom-Firewood-Yard "System". This "Spontaneous ordering" or apparent "negative entropy" took place on a Maco scale over a period of several hours, not nano-seconds. So why is a few seconds of "negative entropy" of a few beads floating in water so Newsworthy ? What is the basis for making a distinction between "animate" and "inanimate" and excluding the latter ? What I am saying is that in order for the "Law" to hold it is necessary to arbitrarily discount "Life forms" as being part of the "System" or to make an arbitrary distinction between "animate" and "inanimate". according to the original formulation of "The Law". This is reflected in the wording of the text or "Laws". i.e. No "inanimate" machine can... such and such and so and so. So what energy was applied to the system that caused the apparent "spontaneous" ordering ? There was a pile of matter on the ground composed mostly of "inanimate" firewood that happened to include a relatively small sleeping life form. Viewed as a simple pile of "inanimate" material, what energy invaded the "system" which suddenly caused a portion of this inert matter to "wake up" and begin putting things in order (stacking the firewood) ? I'm not asking for an answer to that question. I'm just pointing out that "Life" as a factor in the "System" or in thermodynamic calculations has apparently and I think admittedly been excluded as an element. I think this is arbitrary. But this is an entirely different issue than the "Heat" question and probably off-topic for this thread. Just something to think about. ----------------- "II., no inanimate material agency could produce more mechanical effect from a given quantity of heat, with a given available range of temperatures, than an engine satisfying the criterion stated in the enunciation of the proposition." (Source: "The Second Law of Thermodynamics" by William Francis Magie pg 127) "The demonstration of the second proposition is founded on the following axiom: "It is impossible, by means of inanimate material agency, to derive mechanical effect from any portion of matter by cooling it below the temperature of the coldest of the surrounding objects." (pg 116) -----------------------

There is this branch of science called physics and within in there is a subject called thermodynamics. The term "heat" has a well-established meaning within thermodynamics and that definition is the answer to your question. If you choose to ignore that definition, which you may certainly do, then what you are discussing is something other than physics. I think the question was "What is heat ?" Not what is the specialized meaning of the term but literally, What is it in layman's terms. Of course, I do not know that but that is my assumption. I don't think I'm doing that. I haven't argued for applying the term to "something else". I've argued for dropping the term altogether if anything. If the term were not ambiguous to begin with why would anyone ask the question in the first place ? Why any debate about it whatsoever ? and please don't try to tell me I'm the ONLY ONE having some issue with it. I did not start the thread. I've read several. "Thermal Radiation", "Heat Radiation" and "Black Body Radiation" are quite often used interchangeably in thermodynamic literature. As if this were not confusing enough, Heat is said to be "Kinetic Energy" in one breath and some kind of apparently abstract non-material "Thermal Radiation" or "Heat Radiation" or "Black Body Radiation" in the next and this is associated with a "Spectrum" which apparently is the EM or Light Spectrum but is often called "Thermal Spectrum", "Heat Spectrum" or "Black Body Spectrum", In some older text "Heat" is associated with "Infrared" and as has been pointed out this is a common misconception so I think it no wonder that someone trying to understand thermodynamics would ask the question: "What is Heat" Anyway ? I'm probably at least as familiar with the literature as the average person wandering in here and I would also like some clarification. I've proposed some solutions that seem to make things clearer in my own mind. I don't see why I should be censured for pointing out the obvious. It would be nice to have some clarification or "cleaning up" of obsolete terminology IMO.

Because it's a barrier to discussing the concepts if e.g. what you mean by heat is different from what everyone else means by heat. What is the topic of this thread? ~~ WHAT IS HEAT ~~ Defining HEAT is the stated theme of this thread is it not? I think everyone here in one way or another has put forward their definition of the term. What reason would you have for objecting to my doing the same ? There is. You're the only one here denying that thermal sources emit radiation, and that this is considered heat.... I'm simply pondering the ramifications of what is stated on this website regarding "Science Misconceptions" previously quoted: https://www.msu.edu/user/boswort9/cep817web/amasci/scimis.htm To quote one more time: ----------------clip In his book "Clouds in a Glass of Beer," Physicist C. Bohren points out that this "heat" misconception may have been started long ago, when early physicists believed in the existence of three separate types of radiation: heat radiation, light, and actinic radiation. Eventually they discovered that all three were actually the same stuff: light. "Heat radiation" and "actinic radiation" are simply invisible light of various frequencies. Today we say "UV light" rather than "actinic radiation." Yet the obsolete term "heat radiation" still lingers. ... ----------------- It would appear that there is not LITERALLY any "heat radiation" as originally conceived. The belief has been overturned. Heat does not literally radiate. I'm not "denying that thermal sources emit radiation, and that this is considered heat...." I have no particular opinion on the matter. The references previously cited state that to consider such electromagnetic radiation to be heat is erroneous and a holdover from bygone days apparently still taught to High School Students. This is News to me. Do you still hold to the theory of "actinic radiation" as well ? It seems to me that this is more than just a swopping out of one terminology for another. Well, we used to call IT "Heat Radiation" but now we call IT Infrared Light. I certainly don't deny that "thermal sources (as previously defined; i.e. em emitting objects) emit radiation, and that this is considered heat...." apparently by you and others and is a commonly held assumption by nearly everyone including, until now, myself. This reference and others, however, state that this consideration is wrong. EM Radiation is not the same thing as heat. Do you dispute what this reference says ? This seems to me to be a fundamental change in how reality is viewed not just a change in terminology. It was thought that heat itself could radiate. This was discovered to be false, apparently. Something else fundamentally different from heat radiates. This something else is converted to or from Heat at either end but is not itself heat but light. There is no such thing as "Heat Radiation" so why continue to use the outmoded terminology or "consider" something to be something that it isn't ? On the other hand, if you consider heat as universally a substitute term for "kinetic energy" then the problem disappears and the terminology more accurately reflects the reality. Or so it would seem to me. Then you do not have to form arbitrary or artificial distinctions between a photon from a "Thermal Source" and a Photon from any other source when there is apparently no physical basis for making such a distinction. In my mind this clears up a lot of confusion. I'll admit, I could be wrong but that is what makes sense to me at this point trying to reconcile the apparent contradictions. No, that would be you misunderstanding thermodynamics. OK, how so ? I have made an ad hominem attack on you? I have no need of an ad hominem. Your arguments are wrong and can be discussed on their merits (or lack thereof) May I remind you of your earlier statement: "Because it's a barrier to discussing the concepts if e.g. what you mean by heat is different from what everyone else means by heat." Since defining "heat" is the topic of the thread, I would have to perceive this statement as ad hominem and personal even if veiled. You should be arguing with the quote from which the information came, not denying me the right to discuss it. Because the headline is wrong (sensationalized) and the article actually explains some details that might let you know what happened. I don't mean why should I bother, but why should you. "You're wrong" isn't an insult, and if there was any laughter or knee-slapping, I missed it. I saw a lot of "nonsense" and "You are just making stuff up as you go along" but that came from you … I was referring specifically to such comments as: "I'd like to buy a few bottles from his supplier." - "Whatever he is drinking is powerful stuff." Now I don't personally object to a bit of poking fun or whatever now and then but why zero in on me ? Case in point. I take this personally because I'm discussing a reference to a website that stated that "Heat Radiation" is an obsolete conception but instead of discussing the quotation or arguing your point in reference to the citation you point at my "serious lack of understanding of thermodynamics" which may or may not be true but my understanding is not the issue. The statements made in the references are the issue. -----------------clip Physicist C. Bohren points out that this "heat" misconception may have been started long ago, when early physicists believed in the existence of three separate types of radiation: heat radiation, light, and actinic radiation. Eventually they discovered that all three were actually the same stuff: light. "Heat radiation" and "actinic radiation" are simply invisible light of various frequencies. Today we say "UV light" rather than "actinic radiation." Yet the obsolete term "heat radiation" still lingers. ... ------------------

Everybody has a bias, IMO. We are all full of assumptions taught to us from the cradle, most of which we never become consciously aware of. The article suggests repeatedly that there is. I don't know enough about hypothetical future nanobots "running backwards" to form an opinion. No, I admittedly do not understand the second law of thermodynamics. For one thing I would object to anything in scientific circles being referred to as a "LAW". In my mind this is unscientific and stifles the imagination and the possibility of progress. Properly I think it should read the second theory if it is science rather than dogma. Just my opinion of course. I also don't "understand" how a theory that seems to dictate increasing disorder (entropy) is compatible with... well, the Big Bang Theory for one. Life for another. I know all about thermodynamics. I spent most of the afternoon stacking firewood. The pile of firewood went "spontaneously" from a completely disordered pile to a very orderly neat stack. Of course, "I" was involved in the process somehow I think but "I" don't count. Life evolved "spontaneously" on earth. I'm a part of that apparent "negative entropy". You can't hold to the theory of "entropy" (i.e. the second law) without ignoring the obvious fact that you violate it by your existence. Citation? How about this forum and this thread and this conversation. One need not look very far. Sticking with the theme, Take the issue of the evolution of life. You and me. According to the article we are currently discussing it is something of a marvel that some beads floating around randomly in water happened to congregate on one side or the other for a second or two. I say so what ? The eyeball observing the experiment is more organized. Life has become more organized and complex over billions of years it has existed on the planet. Who cares about a brief assemblage of a few beads floating in water ? Arguments to counter this sort of question from thermodynamic or science (particularly evolution) advocates, it seems to me, devolve into mathematical gobbledygook. Take this one for example: http://www.talkorigins.org/faqs/thermo/probability.html Or this: http://www.talkorigins.org/faqs/thermo/entropy.html And the rebuttal from a creationist: http://www.trueorigin.org/steiger.asp I'm not an evolutionist or a creationist so don't bother debating either side of any of these discussions with me. Just pointing out a small fragment of some of the controversy, real or imagined in one small area of interest. Every time some article is published, like the one cited above there are also debates about the article on numerous forums. Why should this be surprising ? I've read and / or participated in a few of them. Like I say, that is a matter of perception and interpretation. What has taken place since the beginning of the universe other than a movement from the total chaos of the "Big Bang" to the mind boggling and largely inexplicable complexities and general orderliness of the universe to be found at every turn today, including life. If we are supposed to exclude or ignore life I would like to know the basis for doing so. Science is about observation not burying ones head in the sand and ignoring what's plain to see. Do you know anyone who has ever traveled to or seen the end of the universe? What exactly constitutes the "ENTIRE UNIVERSE" ? Have you ever heard of String Theory ? It seems to be the latest rage and postulates some eleven or so universes. Or keeping with something more well established than String Theory: The Many-Worlds Interpretation of Quantum Mechanics. How can a "true violation" be defined in terms of an "entire universe" with multiple hidden dimensions as in String Theory or with a potentially infinite number of "parallel universes" as in some interpretations of Quantum Physics and does anyone even have a real handle on THIS UNIVERSE in its entirety ? I doubt it. It is not the term "thermal radiation" specifically, it is the whole concept of Heat in general: It is part of the definition of the science. "her·mo·dy·nam·ics Noun: The branch of physical science that deals with the relations between heat and other forms of energy" "The branch of physics that deals with the relationships between heat and other forms of energy" Well, if "heat" in matter is kinetic energy and "thermal radiation" is obsoleted what does that leave ? But please do not take my philosophical musings on the subject too seriously or personally. I'm not particularly trying to prove or disprove anything. But if the fundamental principle or basic assumptions upon which a science is supposed to be based. In this case "Thermo" (from the Greek: Θερμότητα, meaning heat) is shown to be a fallacy, where does that leave that science ? Open to some question or re-examination I would think. Beats me. Practically every text I've ever read on Thermodynamics makes mention of it: For example: --------------clip Heat death of the universe Main article: Heat death of the universe According to the second law, the entropy of any isolated system, such as the entire universe, never decreases. If the entropy of the universe has a maximum upper bound then when this bound is reached the universe has no thermodynamic free energy to sustain motion or life, that is, the heat death is reached. http://en.wikipedia.org/wiki/Second_law_of_thermodynamics#Heat_death_of_the_universe -------------- Sounds pretty gruesome. If possible, I would prefer not to ignore life.

Well, no, that's actually not what you said. You said "I have no problem with discarding the second law of thermodynamics" True, that is what I said. But I will repeat. I did not say that I was discarding it or that I have discarded it or that I do not think it is important. What is not clear about that ? The following is a clarification of what I did say: "I have no problem with discarding the second law of thermodynamics" I believe that can stand on its own but since you apparently misinterpreted something about that it means: I am not at all attached to it and if it were dis-proven I would raise the flag. I have no problem with discarding the second law of thermodynamics So ? Whats wrong with defining my own terms and concepts for the sake of clarity ? If there is admittedly NO SUCH THING as "Thermal Radiation" why continue to shackle the mind with obsoleted concepts and terminology ? Who's "denying" ? Nature shrugs its shoulders and violates "The Law" with impunity, apparently. Since the atoms making up my fingernail have been spinning and revolving and vibrating for a Bazzillion years. I don't personally know enough about it to form a judgement one way or the other, (thank God) but what I do know is that most of what I learned in school was obsolete before I graduated and the pace of scientific advancement is greater than ever before in history to the point where we are apparently still on this board discussing things and using terminologies that have long since fallen into obsolescence without our even knowing it or anyone who does bothering to make mention of the fact. So I do tend to try and keep an open mind about such things and follow new developments regardless of how "sensational". I would not be too surprised if eventually some astute observer of nature figured out just why as some say "perpetual motion is the rule of the universe " Not at all. But they have not concluded that the second law doesn't hold. Maybe not. but if some such exception or "loophole" were discovered ? Who would be leading the lynch mob ? And what if they did come to such a conclusion ? Would you launch into an ad hominem attack against the person (as you have done with me) rather than considering or debating the issue ? (emphasis added) Well, you should. Because headline writers and journalists have a way of sensationalizing experiments.... Why bother ? If you already know it is just journalist sensationalizing why read any further than the headline ? That's fine, but perhaps you might explain why others get a pass when insulting spin-1/2-nuclei, accompanied by roaring laughter and knee slapping, when he happens to make some sort of misstatement. I thought I was being rather conservative in my jests by comparison. Not to mention some of your comments towards myself have not exactly been complementary. Like most recently, simply considering a possibility or speculating along some lines you don't happen to agree with is... well... In your words: "Call it whatever you want, but it's not physics." or "headline writers and journalists have a way of sensationalizing experiments. If you had read and understood it, as well as thermodynamics,..." I personally find such comments just a bit insulting and ad hominem. I would say that there is some possibility that your prejudice may have slanted your perceptions of the article just on the basis of the headline. I've read numerous controversies and debates over just exactly what is or isn't a violation. It seems to me to be largely a matter of personal perception and interpretation. For all I know the so-called "Law" is pure mythology. A self imposed restriction scientists have shackled their minds with. How can you take something seriously when it is based on a fallacious belief in the existence of "Thermal Radiation" ? When "Heat" itself is proven to be nothing more than motion. How can there be a "Heat Death of the Universe" as apparently dictated by "The Law" if there is no such thing as "Heat" ?

Game over. Just be sure that you know that you are not discussing physics. Call it whatever you want, but it's not physics. Please note that I did not say that I was discarding it or that I have discarded it or that I do not think it is important, just that I have no problem with considering the possibility of discarding it. Many scientists, physicist, theorists etc. have discussed, considered debated "Maxwell's demon" this does not make them, including Maxwell "unscientific". Just picking something at random: Should this sort of thing just be categorically ignored ?: http://www.newscientist.com/article/dn2572-second-law-of-thermodynamics-broken.html Well, yeh, maybe. But go tell it to New Scientist magazine not me. I haven't actually read the article yet BTW but should I just dismiss it offhand ? Or should I consider such information with an open mind ? Which approach is more "scientific". This article was published nine years ago. Any new developments since then since the 2nd law was apparently thrown out the window ? Not possible according to the good Mr. Swansont. This is not Physics. Change and new insights are nowhere on the horizon for Mr Swansont.

Well, a few thoughts, given the new information. I'm going with the hypothesis that "Thermal source of radiation" is an "obsolete" phrase or hold over from before scientists realized that so-called "Thermal Radiation" was, in actuality just light that was at a wavelength not appreciable by the human eye. This, to me, quite effectively simplifies the whole equation when thinking about such matters in a general way. i.e. anything said about "Thermal Radiation" can, from hereon, in my personal information censure be taken with a grain of salt. I have no problem with discarding the second law of thermodynamics. It is statistical, like the number of car accidents. Accidents happen. They can also be prevented. Violations of the second law have been postulated. (Maxwells Deamon etc.) And to one degree or another, I think also demonstrated to a very limited degree, though I wont go there at the moment. Yes, I did notice that swansont earlier pointed out that Infrared Light being heat was a misconception, but IMO misinterpreted this to mean that Infrared light is not the only kind of light that is heat when what was really meant is that Light is not heat PERIOD. Infrared light is not heat. There is no such thing as "Heat Radiation". There is no form of EM emission that is pure "Heat" period as was once considered to be the case. The whole concept of "Thermal Radiation" has been obsoleted. "Thermal Radiation" has not been replaced by "Blackbody Radiation" or "Infrared Radiation" or anything else it has been effectively thrown out the window. Anything ever said about "Thermal Radiation", including expariments performed to "prove" anything related to it could have only been approximations. Why ? Light is almost 100% kinetic energy is seems to me. But not really 100% so it is very close to being pure "heat" or Pure "kinetic Energy" but it is not. Photons can be used to propel a spaceship. (Solar Sails). Light has "pressure" (Radiometer). It exhibits characteristics of a "particle". (Photon). It has many attributes that "Heat" does not have. One of my quotes above said: "For heat to exist there has to be matter". Is light a form of "matter" ? There is some "residual heat" or some form of heat in the vacuum of empty space which is apparently due to the light zipping around in it. So, have we come full circle? Light is not heat. it is mostly kinetic energy but as heat is defined as kinetic energy light is mostly "heat". Though for the sake of simplicity I think it is easier to discard "heat" as a concept altogether as an obsolete or unscientific term based on flawed human perceptions and stick with "kinetic energy" period. There is no such thing as "Heat". It is just a subjective human impression that takes place in the nervous system when there is an increase in (kinetic) energy impacting the nerves.

It is possible to provide links to specific pages though a simple title and page number would be fine if not too much trouble. Or just a title and author as I can search the book or read it myself if you can give assurance that there is some relevant information to be found therein. Ummm... well thanks. I think I understand what you mean by, or what is meant in general by "Thermal Source" at least in this context and why a laser is a "non-thermal source". Thanks. I would like to point out one thing from earlier in this same text though: "improperly used laser devices are potentially dangerous. Effects can range from mild skin burns to irreversible injury to the skin and eye. The biological damage caused by lasers is produced through thermal, acoustical and photochemical processes. Thermal effects are caused by a rise in temperature following absorption of laser energy..." Taken together with your earlier comments regarding lasers and "work", it would appear to me that in regard to lasers at least, this material serves to prove or support my point in regard to light or electromagnetic radiation in general being a form of Kinetic energy not "Heat". I've been doing a bit of additional Googling on the subject of light and heat and have found some arguments put forward by others in support of the my statement that light (in any form) is NOT "heat". I'm presenting these arguments from mostly non-authoritative sources (as far as I know) simply because the individuals making the statements sound at least as sure of themselves as you do and put forward some rather convincing arguments. There are, just by way of comparison, some 50,000 "hits" for the exact phrase (in quotes) "light is not heat". Ummm... "Thermal Source" means basically that the light generated is the result of heating something up to a hot enough temperature so that it gives out light. Like a hot piece of metal in a blacksmiths forge or a light bulb filament. I'm not sure this makes sense either as I thought a laser could be generated from any light source including sunlight but maybe I'm thinking of Indiana Jones creating a laser from sunlight with a ruby to open a tomb and that sort of thing is just fiction (?) Or does only the intermediary "source" count i.e. the Ruby or whatever, and not the original "source". At any rate some other peoples arguments: (a series of three dots ... BTW indicates my editing out of what I consider irrelevant but feel free to read the excerpts in context (links provided) Also I have Bolded or otherwise highlighted some passages or statements I thought were particularly relevant.) This is just from the first page or so of search results. I do not know where any of these people get their opinions from, (except where specific sources are cited) but from what seems to be and purports to be some sort of authoritative source of sorts, (the first cited) the idea that light in any form is heat is just plain old "Obsolete" as I read it. A "Science Misconception" in some old sixth grade text books. I'll await your swift rebuttal as I sift through the other 50,000 or so "light is not heat" results. To be fair, though, the phrase "light IS heat" returns nearly as many search results. Some 40,000 or so, So opinions differ, though on the first page of results I notice #1 This forum and #2 there are statements to the effect of "Misguided science students may wrongly believe light is "heat radiation" " so at this point it is a little difficult to say which way the pendulum swings. As far as "Blackbody Radiation" I wonder about this statement from one of your sources previously cited: "The concept of the black body is an idealization, as perfect black bodies do not exist in nature." The concept apparently refers to any radiating source of EM to one degree or another so really, of what significance is that to our discussion ? According to the above statement the Sun would not be a source of "black body radiation" as such a perfect idealization does not exist. Except perhaps the hypothetical "Hawking radiation" emitted by a Black Hole.

Why the ice? Because the conditions of the problem were that the two containers be at the same average KE. This guarantees that. The issue is that there are multiple variables. If the conditions of the problem require that one of them be held constant, then you hold it constant. Thermodynamics is replete with examples that hold a variable constant, because you get different answers if it's allowed to vary (and often you can't actually solve it without holding a term constant) That's why there are adiabatic processes, isobaric processes, isothermal processes, etc. So yes, it's real scientific. A general rule in science is to, as far as possible, eliminate all possible variables except for the one under investigation. Introducing ICE or any other outside source of arbitrary interference, heat or "cold" is introducing additional variables. This is why I would consider such an experiment more "scientific" if the containers were placed in some form of heat isolation with no outside source of heat or "cold" to potentially skew the results. Your method of compressing gas into two containers while disguising or muffling the heat change and temperature difference generated by keeping the whole system in an ice bath may not violate the terms of the question but it is quite certainly "skewing the results" and no it is not at all "scientific: IMHO. If you aren't going to bother to bother to read the sources, then why ask for them? Why bother with all this if you aren't interested in learning anything? I've been studying "all of this" rather diligently, reading and listening and trying to make some sense of it all. But some of your assertions fly in the face of everything I've come to understand and everything I've ever read on the subject over the past few years. The reason I have been studying all this is because I'm building a kind of heat engine as discussed in another thread which you may or may not be aware of. I doubt you could cite any thermodynamic reference on the internet that I have not already studied in some depth, half a dozen times over. Most of the online references state more or less the same information over and over in more or less the same terms outlining the same principles which are not IMO actually all that difficult to understand. Then you come along with some remark that seems to me to be completely out of left field and has no correspondence whatsoever with established facts as I have come to understand them. Therefore, I am requesting specific quotations from ANY source, preferably authoritative, that specifically backs up your specific assertions as I have already outlined. Such as: "A laser is not a thermal source". You say to me: "If you go to Google and choose the "books" option, and type in "blackbody radiation" you get more than 400,000 hits" So what? Great, so you should have NO PROBLEM backing up your assertion with a direct authoritative quotation that reads, in substance: "A laser is not a thermal source". I see spin-1/2-nuclei has already cited several sources that state the exact opposite. i.e.: "...the laser will be considered as a thermal source..." etc. You simply state that these sources don't mean what they say. You have again repeated this as if it were gospel: "The sun is a thermal source. A laser is not." I'm not going to search through your 400,000 Google hits trying to locate something that isn't there. A search for such a statement on Google in fact turns up nothing beyond your own words in this forum. It is so patently common for a laser to be used as a thermal source that there is a name for it. "Thermal Laser". Put that into Google in quotes and it returns about 200,000 results. Though I'm sure with your rather twisted logic you will come up with some reason why a thermal laser is not a thermal source. So forgive me if I'm not interested in "learning" by being sent on some wild goose chase to try and prove your "logical absurdity" for which you yourself can obviously find no support. If that were true then an object in deep space would not cool down, because the radiation it emitted would not have hit anything. Most of the light from the sun doesn't hit anything in the solar system. Why doesn't it get hotter and hotter? It keep generating energy from fusion. How does it get rid of that energy and maintain a constant temperature, if the EM radiation it emits isn't heat transfer until it hits something? OMG. This is exactly the kind of logical absurdity and contradictions I was talking about when trying to view "Thermal Radiation" as heat. The issues you bring up above disappear when heat (including so-called "thermal radiation") is viewed in terms of kinetic energy. I put "Heat Transfer" in quotes because it is only a manner of speaking. Technically IMO, there is no such thing, it is rather a transfer of kinetic energy. Light is emitted. The photon is then zipping along at the speed of 700 million miles an hour. Seems to me that is a substantial amount of kinetic energy. Heat ? No. Nowhere to be found. Kinetic energy ? Yes and plenty of it. I don't really care if this squares with your way of thinking or not or with the conventional wisdom on the subject or the opinions of long time members of this particular forum. I would be very much interested in any hard data or experimental findings that might shed additional light on the subject. The actual hard data or experiments, and the explaination accompanying such experiments, such as laser cooling, IMO confirm my proposition. The idea that "Thermal Radiation" is somehow some other mysterious form of undetected invisible energy leads to irreconcilable absurdities such as your object in space that doesn't get cold until the "thermal energy" it is radiating hits something. Certainly, whatever your definitions or suppositions, the electromagnetic radiation from the sun is in no way sensible as "heat" until it actually hits someones skin. Before that point it was not "heat" IMO, but rather kinetic energy. motion of a particle (kinetic energy) to the tune of 700 million miles an hour.

In your above post, you seem to be making some tentative acknowledgement that the problem or issue here is mainly a matter of making semantic distinctions dictated by the context. To put this another way: Lets say I have a brother whom we will call "Tony". Tony, my brother joins the army. Where there are very strict rules. It would not be proper etiquette perhaps for other soldiers to call my brother by his first name. In that context, that of the army, my brother is called "Private Booth" or some such. Now my brother is overheard referring to a fellow private as "Bob" instead of using the proper and accepted terminology for that context. He should have used the phrase "private Jones". So as punishment my brother is made to march around the grounds by himself for three hours. Later the same day, he is marching in step with the other soldiers. Later in life after leaving the army, perhaps my brother starts his own business. In that context he is called "Boss" or Mr. Booth or whatever. My point being in all this that whatever the context or the "proper terminology" for that context, my brother is still my brother. The selfsame person. Now, given that, I would also say that light in a laser is no different than light anywhere else as far as individual photons are concerned. Just as my brother marching by himself or marching in step with other soldiers is still the same person. Only the context is different. Now using "the proper terminology" is a good thing as far as helping to define the context but it is IMO misleading when this is taken to extremes or when it is taken too literally. I'm probably going to be ducking out of this conversation soon as I have some projects I'm working on and this is becoming a rather time consuming distraction but, for what its worth, I just wanted to make my position clear as far as "what is heat". If we are going to say that "Heat" is Kinetic energy in one context, or ALMOST every other context, then for consistency I would think it makes sense to consider "radiant energy" or electromagnetic energy, light or photons, "Black body" or otherwise as also being conveyors of kinetic energy and not some distinct form of "Thermal" or "Radiant" energy or "Heat". Now this may not be proper etiquette or may not be the accepted terminology for the context but IMO a Photon is a Photon and viewed in isolation a photon from a "Thermal Source" is entirely and completely indistinguishable from a Photon from any other source just as my brother marching in step with other soldiers is still my brother and still the same individual whether marching in step with other soldiers - which is comparable to laser light where the photons are "in phase" with one another or marching by himself or when acting in any other capacity or context. When considering the question: "What is heat?" I assume that this is a literal question: "What IS heat?" and does not mean; "what is the proper or accepted terminology to use when referring to energy in one context or the other." So what is heat ? What is it literally? In most applications or in nearly every sort of context "Heat" is viewed as or has in fact been proven to be by experiment - Kinetic Energy. I don't personally see any reason for making an exception when it comes to electromagnetic radiation or Photons in whatever context and in fact, this is how laser cooling is explained in all the references I've read on the subject. It is explained and explained quite clearly and completely IMO in terms of Kinetic energy. Considering that there is literally some difference between a Photon in a laser and a photon from some other "Thermal" source just leads to confusion and contradiction IMO. I personally, for whatever it might be worth, find that the "kinetic theory of heat" can be applied most consistently and explains various unusual phenomenon like laser cooling quite satisfactorily whatever the context and find no need to postulate some special exception to the rule in the form of "Heat from Blackbody Radiation". If that is the "accepted terminology" for that particular context, I would say that the "accepted terminology" is inconsistent with the facts. Is there any sort of "photon detector" that can distinguish a photon from a thermal source i.e. a photon that is properly termed "Heat" in some specific context and a photon from some other source ? Not that I've ever heard of. "Heat" in every other context has, I think, been proven to be a transfer of "Kinetic Energy". This has been demonstrated in an untold number of experiments. The distinction or exception to the general rule when it comes to thermal "Radiation" is, IMO, a misleading semantic distinction and nothing more. Heat in any context is LITERALLY kinetic energy or particles in motion whatever the generally accepted terminology might be in any particular context.

If I took the time to read all your supposed references above that presumably are meant to support some one or more of your contentions I'm quite sure I would find that no such support exists therein. How about a specific quote? I'm not going to do your work for you reading everything on the internet to try to find where someone else says something somewhere similar to your "a laser is not a source of thermal energy". Or: "I didn't say "light is heat". I said the light from the sun is heat. It's a very important distinction — " Your only direct quote thus far refutes any such distinction. (i.e. " "Any object at any temperature emits electromagnetic radiation") (Hint: when citing a reference you want to find one that supports your argument not one that contradicts it.) Or: "the sun is emitting blackbody radiation because it's a thermal source and much hotter than its surroundings." Can you please quote a passage from one of your above (or other) sources that give the same or a substantially similar definition of "blackbody radiation" i.e. a blackbody consists of: "a thermal source much hotter than its surroundings". Or specifically that light or any other form of electromagnetic radiation "IS HEAT". You certainly implied as much. Again, the propagation of light is not "heat transfer" until the light hits something. Then there can be transfer of energy on impact which is IMO properly, "kinetic energy". How I "feel" is, as I've stated previously, a subjective impression. I'm going to dismiss the remainder of your arguments as irrelevant as they do not address the issues or are contradictions of your previous statements.

I have read (or heard in lectures) that the energy of a gas (including "internal energy") is in the form of "heat only". Mostly in connection with refrigeration. Specifically Air-Cycle refrigeration where a gas is expanded through a turbine and therefore, in performing work to turn the turbine, gives up "internal energy" and so grows cold, which is how the cooling in such a system is effected. This type of cooling is also one way that cryogenic temperatures can be reached as the gas is made to give up its "internal energy" by doing work to turn the turbine, which "internal energy" presumably refers to such "degrees of freedom" as "spin" or some other "internal" molecular energy.) So I am curious about your statement that "heat is not internal energy". As I understand it heat is "kinetic energy" regardless if that kinetic energy is "internal" or not. That is, a particle can be moving through space as one form of kinetic energy but also has its "internal" kinetic energy which, if removed also lowers the temperature. Can you elaborate on what exactly you mean by "heat is not internal energy". Generally speaking I agree with the later part of your statement. In any case there are better less ambiguous terms. This is why I say "heat" does not exist. Light has physical properties, speed, charge, mass, spin etc. Does "Heat" have any such physical properties whatsoever ? I have never heard of any such physical properties being attributed to "Heat" therefore in what way could it be said to exist (other than as a subjective impression caused by a transfer of kinetic energy from actual particles)? I'm guessing that the reason a gas cools to an extremely low temperature in a cryogenic freezer utilizing an expansion turbine, upon being compressed and pre-cooled and then sent through a turbine is that in being ejected from a nozzle under pressure, the kinetic energies, including "internal" energies are, on average, due to their velocity, more inclined to give up the internal energy. Like lets say "spin" is like my running in a circle. If I were running in a circle on the deck of a boat going under a low bridge and ran into the bridge I would transmit more energy to the bridge than if I just ran into the bridge standing on the ground. In fact, if while on the ground I just ran in a circle without something to carry me along I would not hit the bridge or transmit any of my "internal" energy to the bridge. Suppose I happened to be running AWAY from the bridge when the boat went under ? I would tend not to run into the bridge until I rounded the circle and started back towards the bridge. So my "internal energy" would be added together with the momentum or "external" energy of being carried along by the boat. The molecules being ejected from a turbine nozzle into a turbine are, as if, riding on a "boat" due to the velocity of the mass of air carrying them along. There is therefore two kinds of kinetic energy being given up when they hit the "bridge" (the turbine blades). The result being an extreme drop in temperature.

Real scientific there swansont. I think I've already acknowledge that reaching such a condition is possible, if extra heat is added to one of the containers, (rather than doing the experiments in a vacuum or otherwise having the containers insulated against outside heat exchange). In your scenario, the excess heat from compression in one container (or both) is removed with ice, presumably. So why the ice ? True, temperatures will equalize, but isn't your use of the ice bath an admission that the temperatures have to be artificially manipulated somehow to bring the two back into thermal equilibrium while being compressed? Cooling two containers back to equilibrium with ice does not disprove the kinetic theory IMO, if that is your intention, which seems vaguely to be the case. Though what your actual position on anything might be is impossible to say since it changes with the wind. You have swopped out the words "fixed" and "equal". "fixed" and "equal" don't mean the same thing. No, it does not refer to containers of equal volume, but it does refer to containers of "fixed volume" as it has been repeated here several times, including by yourself that the containers are of different size yes, but that there is no change in volume. Your words: "The example was two containers. Not one container undergoing expansion or contraction. There is no change in volume, there is a difference in volume." "No change in volume" = "fixed volume" No? What has been described is two different containers, each with its own fixed mass and fixed volume. If allowed to sit at ambient for some time Do temperatures equalize? I would think so. Can the heat from compression be lost, Sure. So, in the example given, the bigger container ends up with a lower pressure. Can we agree on that? The smaller container has a higher pressure if both containers contain the same number of atoms right ? That is; if the temperature is allowed to equalize. The individual atoms in the smaller container would then have less "internal energy" (as this was dissipated as heat to the surroundings). The individual atoms in the larger container would have more "internal energy" which they picked up from the surrounding environment. So each could be at the same temperature, once allowed to equalize with the surroundings, ice bath, ambient or whatever but would not have the same "internal" kinetic energy. To prove this, if the volumes of substance were released back into equal size containers (the containers held in a vacuum or otherwise insulated against external heat exchange) the gas from the smaller container would end up colder than the gas from the larger container. Again, refrigeration comes to mind. I don't really know what it is you are trying to prove or disprove, if anything, one way or the other swansont but it seems to me your supposed stance or opinions or certainties on any subject are more or less a shifting sand. The original question was, "what is heat". You said "light from the sun is heat". I pointed out laser cooling. You say ""I didn't say "light is heat". I said the light from the sun is heat. It's a very important distinction" Then end up by quoting: " "Any object at any temperature emits electromagnetic radiation" " So where is the "very important distinction" ? Is a Laser a form of electromagnetic radiation ? Is electromagnetic radiation in any form "Heat", except for lasers ? Round and round we go.

"Pre-compressed" is still compressed. Cooled is still cooled. If I leave a pan of water that I heated up on the stove to cool it does not prove that it was never heated. Certainly, containers, (whatever they might be filled with, or how much) will eventually equalize in temperature, (even containers of different size that contain the same number of atoms, presumably) if exposed to some source of heat like ambient temperature air. Even if I compress gas into one container; like an air compressor tank, the hot compressed air will eventually cool to room temperature, but in the process of cooling the gas will give up energy, which can be proven if it is released back to atmospheric pressure. When released the gas will be colder than it was before being compressed, which is the basic principle behind refrigeration. Compress at ambient -> (temperature increases) -> allow thermal equalization with ambient while under pressure -> release -> temperature decreases. You can imagine that some such thermal equalization never took place, that no heating or cooling ever took place, that no compression or expansion or contraction or whatever ever took place, that these containers appeared ex ex nihilo in such a state by divine fiat or something. and you just ended up with the final result of "pre-compressed bottles already cooled to room temperature" well OK. OK, if others, including yourself, will adhere more closely to rule #4 "The use of logical fallacies to prove a point is prohibited." Can I say that the scenario you describe "pre-compressed bottle which had already cooled to room temperature?" without accounting for or while ignoring the obvious compression, heating, cooling, expansion, pressure changes etc. that must have taken place is a logical fallacy ?

The example was two containers. Not one container undergoing expansion or contraction. There is no change in volume, there is a difference in volume. This "Ideal" scenario being described above, IMO, would also be virtually "impossible" to arrive at under real world circumstances. If I'm wrong, please explain how such a condition might arise. How would one set up such an "experiment" to test this one way or the other ? For example, using air as the "atoms" in the container. To get "the same number of atoms" into each container, since "air" is more or less uniform everywhere on the earths surface, I would have to begin by somehow capturing air in two equal size containers and then expand one container to get the difference in volume. I can think of no method for achieving the circumstance described without in some way doing some sort of "work" on the gas or otherwise manipulating the given or existing natural circumstances. Expand one container or shrink the other. Create a vacuum, put each container inside and release so much gas into each container.... Well, that last might work, maybe. lets see... Perfect vacuum in both containers. Both inside a perfect vacuum. The vacuum acts as a perfect or near perfect insulator. All the atoms released start out at the same temperature. They may have to be filled SIMULTANEOUSLY in some way because if one is filled first, the tank or whatever from which the filling is taking place would have undergone some change in pressure and temperature. The same number of atoms are. in such a fashion, released into each container. There is no other heat transfer in or out of either container. There is, presumably, some form of thermometers that can be read (and whos temperatures have been previously somehow equalized) already placed in each container before the vacuum was initiated in each container. So now we're all set, we've filled each container and we read the thermometers,... are the temperatures the same ? I would say NO. In the larger container the molecules have more room to move about and so collide with the thermometer less frequently. So whatever your abstract concept about the ideal situation might be the actual temperature reading from the actual thermometers in such an experimental circumstance would IMO be different. Not only the temperature, but also the pressure would be different. The pressure, from whatever source the containers were filled, would build up more quickly in the small container. The large container being larger, it would never achieve the same pressure as the small if filled with exactly the same number of atoms. The effect would be the same as expanding or contracting one container or the other. Certainly I would think such an experiment would already have been carried out ages ago by some notable like Joules or Thompson. Lets just make up a name shall we ? Some guy back in 1702 with some ridiculous name like Guillaume Amontons did this experiment and lets call what he discovered "Amonton's Law" which states that "the pressure of a gas is directly proportional to its temperature" or something like that. Or maybe it was Charles or Boyle or Avogadro. One of those guys I'm pretty sure has already done some such experiment. Oh, wait, Guillaume Amontons is a real guy! sorry. Go figure. http://en.wikipedia.org/wiki/Gay-Lussac%27s_law#Pressure-temperature_law

I didn't say "light is heat". I said the light from the sun is heat. It's a very important distinction — Utter nonsense, More nonsense. At this point all I can do is point you to a physics textbook or class and suggest you pay attention to where they talk about the methods and details of heat transfer: conduction, convection and radiation. Ummm... I'm sure that if your absolutely ridiculous contentions are somewhere close to being within the sphere of some kind of REALITY outside of your IMAGINATION you could easily cite some online source and not use the above COP OUT. First of all, I don't think light from the sun is somehow particularly somehow SPECIAL or DIFFERENT from light from other sources in the way you seem to think, though I can't really imagine in what way you think this might be. Second of all, I don't think you actually understand the meaning of the term "Blackbody" of "Blackbody Radiation" if you imagine that the term applies only to the SUN or electromagnetic waves or Photons from the sun and not say - the heat lamp keeping the french fries warm in a fast food restaurant. There is no TRANSFER of HEAT where a photon is flying through the vacuum of empty space. A photon is not HEAT whether it comes from the sun or anywhere else. There is no qualitative difference between an individual photon in a laser and an individual photon anywhere else in the universe to my knowledge. You are just making stuff up as you go along IMO. Reaching for straws. You imply by your above statements that light from the sun is "...a thermal source and much hotter than its surroundings". And, apparently mean to imagine that an ordinary incandescent light bulb is not "...a thermal source and much hotter than its surroundings". You say "A laser is not a thermal source — it emits a very narrow range of frequencies and is not at all like a blackbody" Utter nonsense. If a laser "is not a thermal source" than pray tell, how or why is it routinely used in various industrial applications for generating heat for cutting and welding ? Anyway, "A thermal source" is not heat. Its a thermal source. The sun or a common light bulb are both "thermal sources". Light is light. Light is not Heat. A photon or light in transit is not the same thing as a "heat transfer". The "heat transfer" if any, takes place at the point of impact. Light itself, from the sun or anywhere else, viewed as a THING or OBJECT in isolation, is not "HEAT". Unless of course you assume that light (or a photon) emitted from the sun is also absorbed by the skin of a sunbather on the beach instantaneously or emitted and absorbed simultaneously with no intervening transit through space or time. Even if this were true, how would this be any different from a "sunbather" using artificial light in a tanning salon ? Can you cite even one published source - online or otherwise ((i.e. in an actual textbook with an author and title and/or ISPN number so that the reference can be looked up)) in support of your amazingly silly contentions I have found objection to here ? Like: "I didn't say "light is heat". I said the light from the sun is heat. It's a very important distinction — " Says who? Or: "A laser is not a thermal source — " Says who ? Or: "the sun is emitting blackbody radiation because it's a thermal source and much hotter than its surroundings." You purport here to provide some kind of definition of "blackbody radiation" that matches up quite completely with nothing at all that I've ever read on the subject.

Why is it impossible? I think I already explained that, but whether it is "impossible" or not would depend on what YOU mean by "average kinetic energy". I don't think you can disregard volume. Like, "on average, how many ears of corn are harvested?". This is incomplete and makes no sense. The question should be "on average, how many ears of corn are harvested per acre?" If I have one packet of seed containing 200 corn seeds and I plant 100 in a one acre plot and the other hundred in a 10 acre plot it is virtually "impossible" for the "average yield per acre" to be the same. In one plot the seeds would be much more spread out than in the other. 10 corn stalk per acre vs. 100 stalks per acre. But it is not entirely "impossible" for the "average yield per acre" to come out the same if there were some extraordinary circumstance such as the 10 acres planted with the 10 seeds/acre were provided with much more fertilizer (extra heat from the stove burner in the previous example) than the one acres with 100 seeds/acre. Ummm... Yeah, I think so. I'm guessing that is why the equations like PV=NRT and such all have that "V" in there somewhere: --------------------------- The state of an amount of gas is determined by its pressure, volume, and temperature. The modern form of the equation is: PV = NkT where P is the absolute pressure of the gas measured in atmospheres; V is the volume (in this equation the volume is expressed in liters); N is the number of particles in the gas; k is Boltzmann's constant relating temperature and energy; and T is the absolute temperature. http://en.wikipedia.org/wiki/Ideal_gas_law ---------------------------- But this is all rather new to me. I just started trying to figure this stuff out myself about a year or so ago so I'm no expert.

Theoretically, I believe that is supposed to be the case as it has had "work" done upon it. The rise in temperature may be infinitesimal in this case but you have pressure from fingers against the ball squeezing the ball, friction against the hand and against the air transferring energy etc. If you compress a gas the temperature rises in part due to work having been done by the piston or whatever in the compressor pushing the gas. This is also true of a solid. Stand on a chair and the extra weight will raise the temperature of the chair slightly. A window fan raises the temperature of the air it pushes as the fan is doing work against the air etc. etc. In ordinary circumstances temperatures will equalize quickly but under controlled conditions such changes can be and have been measured. http://en.wikipedia.org/wiki/Mechanical_equivalent_of_heat Since there is no such thing as heat: I don't know how I'm going to cook my beans or what I'm going to do to keep warm this winter. If you carry a wooden wagon wheel to the top of a hill it has "potential energy" to roll back down right ? If you break the wagon wheel up and use it to build a camp fire on the top of the hill... what happened to the "potential energy" ? Where can I find the "potential energy" that was "stored" in the wheel or any such object; bowling ball, water balloon car tire or whatever; carried to the top of a hill ? I would submit that there is no such thing as "potential energy" any more than there is "heat energy". They are just convenient fictions.

OK sticking by your trusted source to quote again more specifically: "An object does not possess "heat"; the appropriate term for the microscopic energy in an object is internal energy." Further down the page: "To describe the energy that a high temperature object has, it is not a correct use of the word heat to say that the object "possesses heat" - it is better to say that it possesses internal energy as a result of its molecular motion. The word heat is better reserved to describe the process of transfer of energy from a high temperature object to a lower temperature one. Surely you can take an object at low internal energy and raise it to higher internal energy by heating it. But you can also increase its internal energy by doing work on it, and since the internal energy of a high temperature object resides in random motion of the molecules, you can't tell which mechanism was used to give it that energy." This author says: "The word heat is better reserved to describe the process of transfer of energy from a high temperature object to a lower temperature one." and also: "Don't refer to the "heat in a body", or say "this object has twice as much heat as that body". He also objects to the use of the vague term "thermal energy" and to the use of the word "heat" as a verb, because they feed the misconceptions, but it is hard to avoid those terms. He would counsel the introduction and use of the concept of internal energy as quickly as possible." More semantics. Take this statement: ""The word heat is better reserved to describe the process of transfer of energy..." What type of "energy" specifically ? And again: "it is not a correct use of the word heat to say that the object "possesses heat" - it is better to say that it possesses internal energy..." Again, what type of energy are we talking about when saying "internal energy" ? The author states "molecular motion" and / or "random motion of the molecules" which equates to kinetic energy, does it not ? I don't feel a need to apologize for my sources, they were picked at random from a cloud of search results simply to show that it is commonly understood by virtually everyone with an opinion on the subject that heat (thermal energy) is really kinetic energy or molecular motion. If as you stated earlier that LIGHT IS heat then please explain how a laser can cool atoms to near absolute zero. If light were heat there would be no way to cool anything by bombarding it with laser light as demonstrated with the Bose Einstein condensate experiments cited earlier: http://www.nobelprize.org/nobel_prizes/physics/laureates/1997/index.html How does laser cooling work ? "...the kinetic energy of the atom will be reduced. Since the temperature of an ensemble of atoms is a measure of the random internal kinetic energy, this is equivalent to cooling the atoms." http://en.wikipedia.org/wiki/Laser_cooling Bottom line in my opinion: Assuming the kinetic theory of heat has led to successful experimental results. It has a good track record in terms of predictability. It leads to predictable real world observable effects such as laser cooling which IMO would be impossible if the theory were false or certainly would not be possible if light itself were heat. Sure, light carries energy that can, under certain circumstances be converted into "HEAT" (i.e. an increase in kinetic energy) but light is not heat. "Heat", or an increase in kinetic energy can take place in numerous other ways I believe, in the total absence of light. can it not ? If light were heat then there would be no possibility of "heat" transfer without light. As far as I'm aware there is no such necessity to have light present to effect "heat" transfer. All you need is to have one molecule bump against another (i.e. transfer kinetic energy). Such a transfer could be one air or gas molecule against another. As far as I'm aware there is no light involved in such a transfer of kinetic (heat) energy. Perhaps you missed this page from your source: http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/kinthe.html Or this one: http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/kintem.html

Thermal energy is not heat, either. From that link: When two thermodynamic systems with different temperatures are brought into diathermic contact, they exchange energy in form of heat, which is a transfer of thermal energy from the system of higher temperature to the colder system. Note it is not the thermal energy itself, contained in the system. It's the transfer. I still say you are just getting tied up by the semantics. #1."they exchange energy in form of heat" which is: #2 "a transfer of thermal energy" These two statements are stated to be equivalent Statement #1 "which is" Statement #2 exchange = transfer thermal energy = heat Putting it back together: "they exchange energy in form of heat, which is a transfer of thermal energy" or: ""Microscopically, the thermal energy (= heat) is the kinetic energy of a system's constituent particles" "Heat is Kinetic Energy" http://www.vias.org/physics/bk2_03_02.html "Thermal energy (heat) is kinetic energy" http://mineral.gly.bris.ac.uk/geochemistry/pdflectures/Thermodynamics1.pdf "Heat (or thermal) energy is kinetic energy due to motion of atoms and molecules." http://okfirst.mesonet.org/train/meteorology/HeatTransfer.html Stating or pointing out "It's the transfer" does not negate the fact that heat or thermal energy is kinetic energy. The word "transfer" itself implies motion or kinetic energy. So sure, yeah, it is "the transfer" A transfer of kinetic energy to my skin is interpreted by my nervous system as "heat" but there is no actual "heat particle" or "Heat" as such - as a thing in itself - being transferred. There is no such thing. You cannot separate "Heat" and put it in a bottle.

You may or may not be correct. Suppose you have two containers, one larger than the other. Let each contain the same number of atoms of the same gas, and let their average kinetic energies be the same. In that situation, will the both have the same temperature? Well for one thing, the scenario you describe is impossible. In such a situation, the "average kinetic energy" in relation to volume at least could not be the same. If it were possible to put ones hand into each container, one would feel warmer than the other as in the large container the atoms would be spread out more and would "bump into" your hand less frequently. But no, they would not have the same temperature but also the kinetic energy could not be "the same" either. If you put a thermometer into each container, one thermometer, due to being bumped into by more atoms because they are squeezed closer together in a smaller container would have more energy transferred to it and so the mercury molecules in the thermometer would expand more. In the larger container, due to the atoms being more spread out, the thermometer would be bumped into less often and so would read a lower temperature. Each individual atom might have "the same" kinetic energy in terms of speed of travel but the "average" kinetic energy as measured by lets say square inch of volume of gas would not be the same. There would be fewer atoms per whatever volume of gas in the larger container therefore the "average kinetic energy" for each unit of space could not be "the same" for both containers. Unless... If you applied more "Heat" to the larger container. That is, if you put the larger container on a stove and heated it up then the gas molecules or "atoms" would move faster. But this does not make "Heat" a "Thing". The molecules in the stove element are just moving faster and imparting their kinetic energy to the larger container whose molecules move faster so as the gas bumps into the sides of the container more kinetic energy is transferred to the gas inside the container. Then due to the gas in the larger container being more energetic the temperature and the "average kinetic energy" could be the same but it is arguable if a specific gas at different energy levels is "the same gas".

Practically speaking, in this context, they amount to the same thing. "Heat" in a gas or otherwise is kinetic energy. No, temperature does not EQUAL heat. Temperature is a measure of heat but you are just playing semantic games there. The question is: "What IS heat?". "IS" implies an existence or actuality. A measurement is not the thing measured. "Heat" is not an IS (existent thing) either. Not a thing in itself. -------------- "Microscopically, the thermal energy is the kinetic energy of a system's constituent particles" http://en.wikipedia.org/wiki/Thermal_energy -------------- You can talk about the kinetic theory of Gas, Heat, or Matter, they all amount to the same thing that heat or "thermal energy" is kinetic energy. What distinguishes different states of matter, solid, liquid or gas is the relative motion of the particles. I've never seen a "heat" object represented in a particle collision (bubble chamber) or in a feynman diagram. There is no "heat particle" or existent "thing" or object, particle, wave, solid, liquid or gaseous or any other substance or entity "HEAT". You have degrees of relative motion of particles, fast, slow or whatever. There is, it seems to me, no such thing as "thermal energy" other than as a convenient manner of speaking in terms of subjective human experience or observed effects such as mercury rising in a thermometer. The reason the mercury rises, however, is due to a transfer of kinetic energy or molecular motion not any kind of actual "heat" entity. If you want to know "What is heat?" there is no such thing. Its just a conceptual framework for describing in terms of human experience something not directly appreciable via human perception. We cannot see the motion of the particles but we can feel the subjective impression of that motion as so-called "Heat". "Light from the sun is heat" ? "Visible range" ? Visible range of what ? Heat ? I don't think you have any idea what you're talking about. Maybe I don't either but I'm not pretending to, at least I'm not making dogmatic assertions without foundation or supporting references. Light, infrared, visible or invisible is not heat. People often associate heat with infrared light but light, infrared, "from the sun" or otherwise is not heat. Heat might be called a property of light or maybe you could say that light carries heat/energy or something but to say light IS heat is like saying a soccer ball is a kick or a fist is a punch in the nose.