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 Subject: E=MC2 simplified Category: Science Asked by: davidetal1234-ga List Price: \$10.00 Posted: 20 Feb 2005 21:58 PST Expires: 22 Mar 2005 21:58 PST Question ID: 477866
 ```Are the following observations accurate: "E=MC2 shows that Energy converts to Matter or vici versa at the speed of light squared. Speed, or velocity, to use the correct term, is a measure of time. Time is a measure of something happening in space, so we think of space-time as a single dimension. Throw a log on the fire. Watch as matter is transformed into heat energy. Note that this is happening in time and space, and we have arrived the core of Einstein?s equation." Is E=MC2 really that simple, in its essense?```
 Subject: Re: E=MC2 simplified Answered By: siliconsamurai-ga on 21 Feb 2005 05:48 PST Rated:
 ```Hi, thank you for submitting your question to Answers.Google, I believe I can provide the information you are seeking. Since 2005 is the International Year of Physics, this is a great question. Sorry to say, your idea has no relationship to Einstein?s discovery or the famous equation. Briefly, remembering that since about 1880 or so it has become increasingly impossible to really discuss details of anything in physics in English or other language without benefit of mathematics, what the equation says is that matter and energy are two forms of the same thing and that you convert between the two by either multiplying or dividing by the speed of light squared. But this conversion is just like converting between inches and centimeters, it isn?t an explanation, it is just a number. The equation says nothing in particular about time or the speed of conversion, in fact, although time is a component of speed, this equation squares speed and time squared is meaningless, at least in this context. See http://www.madsci.org/posts/archives/sep2001/1000903792.Ph.r.html This irreverent look at the question actually offers a pretty good explanation: http://www.stresscure.com/hrn/einstein.html How he came up with the equation is relatively simple, so to speak. He saw that an easy way to explain some experimental results by others was to assume that the speed of light was constant. By using the speed of light as a constant in some earlier equations of physics, one result that popped out was that e=mc*2 which surprised a lot of people, including Einstein. The equation says nothing about how to convert either direction, it just provides an equation for determining the magnitude of the conversion. You will find a simple, algebraic derivation at: http://www.kineticbooks.com/physics/17467/17514/sp.html Space time is not a single dimension; Relativity says that space and time are made up of 4 dimensions. This has since been surpassed most recently by super string theory or M (manifold) theory which, the last time I checked, required 11 dimensions. en.wikipedia.org/wiki/M-theory You can find a calculator and explanation of the equation at http://www.1728.com/einstein.htm You?ll find a simplified explanation of Relativity vs Classical Mechanics at: www.newtonphysics.on.ca/EINSTEIN There is an FAQ on mass energy conversion at: http://www.newtonphysics.on.ca/faq/generalization.html Find a look at the famous equation at: http://www.eequalsmcsquared.auckland.ac.nz/sites/emc2/ Go to www.discovery.com and search on relativity: Please don?t feel bad about getting the idea so wrong. It is simply impossible to discuss modern physics in any meaningful sense using any language other than mathematics. This started about the time Einstein began his work and went completely out of control in the mid-1920s when quantum mechanics was created. Think I?m exaggerating? A friend of mine at Harvard won the Nobel Prize for his work on quantum mechanics. It took almost 50 years for experts to realize what he had actually contributed and award the prize. Also, quantum mechanics was essentially invented twice in two different mathematical forms and it took years to even demonstrate that they were equivalent. Modern physics is complicated and you can make contradictory statements about it in English which are both true because they aren?t contradictory in the language of physics which is math. Another thing to remember when people say one theory has proven another wrong and such is that Einstein worked mostly with constant velocities, not acceleration. Google search term: meaning of mc squared Thank you again for turning to Answers.Google for help. If a lot of people add comments saying how wrong I am. They may be correct in part but I ask you to remember that this was a simplified explanation of something which takes years of study and an understanding of mathematics at the level of differential equations at a minimum and preferably a working familiarity with tensor analysis to really explain and, unfortunately, also to fully understand the explanation. One rule we had when I studied physics was, if it makes sense it is probably wrong. We also used to say about some relatively easy proboem, "Hey, it's only rocket science, not quantum physics." I hope I have encouraged you to continue delving into the fascinating field of modern physics rather than turning you off completely.``` Request for Answer Clarification by davidetal1234-ga on 21 Feb 2005 18:01 PST ```Thanks v. much, siliconsamurai, for your answer. Having read through your answer and the links I remain confused about some things (well, many things actually, but we need not go there!) and write to seek clarification: 1) On some sites I found people talking about M = Mass; others as M=Matter? So, although this is as basic as it gets, are there terms equivilent..as in mass is a measure of matter?? 2) I wrote: " E=MC2 shows that Energy converts to Matter or vici versa at the speed of light squared" You wrote: "what the equation says is that matter and energy are two forms of the same thing and that you convert between the two by either multiplying or dividing by the speed of light squared". I understand the distinction - I *think* - between my treating E and M as two different things (which transform into each other), and your statement that they are two "forms" of the same thing. This is an important semantic (if that is the right word). This means that the rock and the gravity acting on that rock are two "versions" of the same underlying reality; and that there is no such thing as 'pure matter" (hence no Absolute Zero) and no 'pure energy'. Happy with this understanding...Clarication sought: have I understood you correctly? 3) Then you added: "But this conversion is just like converting between inches and centimeters, it isn?t an explanation, it is just a number." This seems terribly important to me. I understood from it that we cannot (yet) explain exactly *how* one form (eg: E) converts into another form (M), but all we understand is that it does, and does so at C2. Have I understood this correctly? This M-theory/string theory stuff is the search for the explanation...yeah? 4) The references in comments to atomic bombs and nuclear fusion...I get that M transforms into E in this process, and people get killed. But I still fail to get why we cannot understand why *any* tranformation of M=E ...such as the log in the fire ....is not identical in principle at least to what happens in an atom bomb. 5) Finally!!...if all this clarification amounts really amounts to a 'new question', then please let me know what tip to would be appropriate..., as I would be most grateful for your response! Thanks v. much David``` Clarification of Answer by siliconsamurai-ga on 22 Feb 2005 06:35 PST ```HI, OK, I?ll try but I can?t make it much simpler without introducing too make misstatements which would lead you even futher astray. Re: matter vs mass 1)Matter is the state of energy which is what you probably think of as solid. Mass is the amount of that matter. The sites which ?confuse? the two are simply trying to reword things so more people understand. Mass is the actual quantity of Matter. 2)The distinction is that nothing in the equation implies how quickly anything is being converted. Nothing known except light (actually, the theory of Relativity says that nothing capable of carrying a signal) occurs at the speed of light, certainly it doesn?t occur at the square of the speed of light. When you square light velocity and multiply by mass, the new unit you get is energy. Just which unit of energy (erg, joule, hoursepower, etc.) depends on which units you use to measure mass and which you use to measure velocity. Gravity ? The Theory of Relativity says that gravity doesn?t and can?t ?act? on anything, gravity is a characteristic of the shape of 4-dimmensional space time. (up/down, right/left, back/forward, and duration) ?Pure matter? is a nonsense term with no meaning in this context, so is ?pure energy.? That is, there is no such thing as ?impure energy? or ?impure matter? in Relativity. ?Absolute zero? can?t be reached because matter has a tiny amount of atomic motion no matter how much you cool it. This has little or nothing to do with Relativity. 3) You sort of have it right as long as you remember that c*2 is just the conversion factor. Cheer up, getting it ?sort of right? is about all you can expect from looking at this in any language other than mathematics (and sometimes even then, that?s one reason why there are lots of engineers but there aren?t very many physicists.) String theory is the latest attempt at a unified field theory which Einstein tried to develop for about 45 years with absolutely no success. The UFT is an attempt to link all physical theories together ? the practical result might be anti-gravity and such. Here?s the situation from the time of Maxwell, who demonstrated that electricity and magnetism are closely related and wrote a few very basic equations demonstrating that. Einstein produced a theory of gravity which said gravity is essentially just the shape of space which is distorted by any mass. The usual demonstration is to place a weight in the center of a sheet of rubber stretched on a frame, then roll a marble across the surface. The path is exactly what we would expect if the weight were exerting a ?gravitational? pull on the marble (when you include friction.) The Grand Unified Field Theory would show how gravity is related to electromagnetism. This is all very simplified. If you would like to post a question on string theory (also known as M or Manifold theory now), I, or someone else can explain that. 4) GREAT Question! Yes this part you have right, ANY transformation of M to E is exactly equivalent to a nuclear reactor, an atomic bomb, what happens inside a star, or when a subatomic partical decays. The problem is, if you burn something, such as a piece of paper in a sealed container filled with air or oxygen, no mass is converted to energy. The weight never changes even a tiny amount. Fire is a chemical reaction (exothermic ? that is, it released energy) but it does NOT convert mass into energy, it merely releases chemical energy stored in the matter. An endothermic (energy absorbing ? sort of) reaction is required to make explosives or to grow a tree. All that happens when you burn a log is that a good portion of the sunlight and chlorophyll reaction which converted basic minerals into the wood, is release in a very short time. When you burn something all the original elements (carbon, oxygen, nitrogen, etc.) remain in exactly their original amounts, they are just changed in form, for example, a lot of the carbon combines with oxygen to become carbon dioxide CO2 and a lot of the hydrogen combine with oxygen to become water H2O. Nuclear reactions, even very small ones which are occurring in your body all the time such as isotopes decaying, actually involve a change in mass and are thus covered by E=MC*2. When you combine hydrogen in a basic fusion reaction you no longer have hydrogen, you get energy plus a new element. When you break up uranium or plutonium, you get several different elements. In both processes the mass of the latter is less than the mass or the former, hence they produce energy by destroying mass. To a great extent you can say that physicists understand exactly how and why this happens. Finally, Yes, I feel that most of this clarification does amount to an entirely new question in my opinion but that?s up to you to decide. I just hope I have been of assistance ? don?t feel bad, this is NOT a simple subject, it is just a lot simpler if you understand the math. As always, please remember that this is a very simplified explanation, anyone with knowledge of physics could find a dozen ?mistakes? but that is because it is simplified, not because I don?t understand the concepts. If you want an explanation of string theory from me just post the question to my attention, although you will really need to understand quantum mechanics first and remember that as you progress from Newtonian mechanics to Relativistic mechanics to Quantum mechanics and beyond, it gets progressively more difficult to put into words - most scientists of the time couldn't understand Relativity and the next generation which understood Relativity fought tooth and nail against Quantum mechanics because they didn't understand it. Since I also restore cars and used to re-engineer heavy equipment I sometimes tell people I am a factory trained mechanic - car, truck, Newtonian, Relativitistic, and Quantum. Let me know if this didn't answer your questions.```
 davidetal1234-ga rated this answer: and gave an additional tip of: \$5.00 ```Your answer and the subsequent clarification were extensive and thoughtful. I can't really say that they answered my question BUT ONLY becuase I have learned from you that I did not really know what I was asking! So that really is the answer to my question! The result: I know much more, including knowing what I dont know...and I will continue musing muchly about the mysteries of E=M^2...Thank you. David```

 Subject: Re: E=MC2 simplified From: xarqi-ga on 20 Feb 2005 23:05 PST
 `No. Those observations are not accurate. They are not even close.`
 Subject: Re: E=MC2 simplified From: siliconsamurai-ga on 21 Feb 2005 07:27 PST
 ```Just a reminder, xarqi's accurate comment was about the original question and posted before my answer, although he/she may have something to say about my answer too (GRIN).```
 Subject: Re: E=MC2 simplified From: ticbol-ga on 21 Feb 2005 11:31 PST
 ```I like you, siliconsamurai-ga. I did not, and will not, read any of the links you showed above but I believe you. I thought E=mc^2 meant the potential energy stored in a matter is equal to the mass of the matter multiplied by the square of the speed of light. I thought it is related to the explosive power/energy of atomic bombs. When I was young, after I learned about E=mc^2 in Science in Grade school, I wondered at the power that a piece of my finger nail that I had just clipped if it were made into an atomic bomb! If they can make that devastating bomb from an atom, how much more would it be if they use a piece of cut finger nail? (How simple the mind works when you are young.)```
 Subject: Re: E=MC2 simplified From: siliconsamurai-ga on 21 Feb 2005 11:55 PST
 ```ticbol Yes, you were almost exactly right as a youngster, the equation is related to atomic power. Although there are other energies involved, most of the energy in an atomic explosion is from the destruction of a tiny amount of matter, or rather it's conversion into energy - it takes quite a big effort to initiate the conversion which is why everyone was so excited at the possibility of cold fusion which has disappeared from the headlines but is still being quietly worked on by a few people.```
 Subject: Re: E=MC2 simplified From: xarqi-ga on 21 Feb 2005 18:31 PST
 ```To siliconsamurai-ga: Yes, I have something to say about your answer: it was superb!```
 Subject: Re: E=MC2 simplified text notation From: siliconsamurai-ga on 22 Feb 2005 09:01 PST
 ```By the way David, I didn't want to complicate or confuse things further and it didn't really matter in this instance, but just for future reference, the usual way to write an equation like this in plain text is E=MC^2 where the "^" symbol indicates raising to a power or you could write E=MC*C. Where I wrote MC*2 was definately not correct but I felt it would make sense to you while you probably hadn't seen that use of the "^" symbol.```
 Subject: Re: E=MC2 simplified From: richard-ga on 22 Feb 2005 16:00 PST
 ```Siliconsamurai-ga Please reconsider your assertion that "if you burn something, such as a piece of paper in a sealed container filled with air or oxygen, no mass is converted to energy. The weight never changes even a tiny amount." I believe the following sources are reputable: "Even in chemical processes there are tiny changes in mass which correspond to the energy released or absorbed in a process. When chemists talk about conservation of mass, they mean that the sum of the masses of the atoms involved does not change. However, the masses of molecules are slightly smaller than the sum of the masses of the atoms they contain (which is why molecules do not just fall apart into atoms). If we look at the actual molecular masses, we find tiny mass changes do occur in any chemical reaction." http://www2.slac.stanford.edu/vvc/theory/relativity.html "The well-understood heat that was given off in a chemical process was long supposed to be a product of "energy" somehow stored in the atoms of the elements involved. But Einstein became suspicious that the very mass of the atoms themselves were somehow the source of the heat--that heat (as energy) was the result of a transformation of a small amount of mass itself into energy form. In fact, mass was itself merely stored energy. He thus hypothesized that the amount of energy given off in a chemical reaction was measurable in terms of loss of mass in the elements involved. In the end, he came up with the well-known theory that energy (E) contained in something was equatable to the product of the mass (M) of that same something and the speed of light times itself (c2) or E = mc2." http://www.newgenevacenter.org/biography/einstein2.htm "Mass and energy are very different properties of matter, and E=mc2 applies just as much to chemical reactions (a burning match) as it does to reactions in the nucleus (the burning of the stars)." http://www.ccmr.cornell.edu/education/ask/?quid=590 "Einstein's mechanics applies equally well to any chemical reaction. In a chemical reaction the amount of energy released in each interaction represents a very small mass equivalent. So we do not notice the difference between the mass before and after the reaction. In chemistry we use the law of conservation of mass but it is not precisely correct. The need to use relativistic mechanics is more evident in nuclear reactions. Perhaps that is why we associate Einstein more with nuclear energy than with chemical energy." http://www.jnp.hume.ca/cdbook/MCH12.html Thanks! Richard-ga```
 Subject: Re: E=MC2 simplified From: davidetal1234-ga on 22 Feb 2005 19:29 PST
 ```Siliconsamurai (and Richard GA) Thanks for your efforts guys. Deeply appreciated. Didn't know that this was the Year of Physics, but maybe this is why the universe has deposited questions about physics in my brain! What follows is just some comments on all the comments; feedback if you like from your 'student'! I must say that I was most relieved to read that chemical reactions 'obey' E=MC^2. Not sure why, but perhaps it has something to do with me being able to strike a match and watch E=MC^2; no high maths involved! I now see that 'hidden' in E=M^2 is a third or underlying variable. That variable is 'matter'. Hidden, at least, to me! The equation tells us - I have now learned - that 'matter in its Energy form' may convert to 'matter in its Mass form' and if this happens, the amount of Energy that is released is a product of Mass and the number C^2. In chemical reactions, the amount of "matter in Mass form' that converts to 'matter in Energy form' is tiny (logs on fires); in nuclear fusion, the amount is very large (suns and atom bombs). Given this, I can source a lot of my confusion about the equation to 'M' and my treating it as Matter, when in fact it stands for Mass. Yeah yeah: I am sure a slow learner! Given this, there are several questions which are immediately begged: *why "C^2" in the equation? Is this arbitary given given that C^2 is not real in any sense, as nothing happens faster than C. Referencing siliconsamurai's earlier observation, if it really is just a conversion number (like fareignheit to centegrade), could we use another number if we wanted to? I have now read that Einstien's breakthrough was around treating the speed of light as a contant - hence C - but the question I think still stands. Put more clearly perhaps: 'what **information** do we glean from using C^2 which some other massive number wouldnt give us? * if E and M(ass) are forms of matter ...or to quote one of the websites....a "property" of matter...or 'versions of matter'...are there any other forms/properties/versions which matter takes? Putting notions of God to the side, I'm pretty damned sure that I would have heard if there were any! * back to this 'pure' business: matter is ***always*** a combination of E and M as proven by Absolute Zero never having been reached. This tells us something very important: E=MC^2 is a description of matter. 'matter' is never equivilent to just E or M; it is always and only equvilent to "E=M" in some combination. Expressed another way: all Mass contains Energy (sub-atomic particles/('strings'?) which are moving); all Energy contains Mass (all movement contains some sub-atomic particles/'strings'). Thus, matter is a combinatin of Mass and Energy. And that is the nature of reality. Therefore **'gravitons'** have to exist, even though we have yet to find them! Sheesh. Feel I am streching way past the boundaries of GA etiquette in raving on like this, so please ignore all of the above if it is rude to carry on in this way, and, again, thanks v. much for your illumination of my poor brain! David```
 Subject: Re: E=MC2 simplified From: siliconsamurai-ga on 23 Feb 2005 05:20 PST
 ```David, I'm sorry to have to point out that you have missed one of the most important points. "In chemical reactions, the amount of "matter in Mass form' that converts to 'matter in Energy form' is tiny (logs on fires); in nuclear fusion, the amount is very large (suns and atom bombs)." In a chemical reaction NO MATTER IN ANY FORM CONVERTS TO ENERGY. Chemical reactions have no connection with the famous equation any more than the potential energy of a car parked at the top of a hill has any connection with the mass energy equation despite the fact that it would be very destructive and a lot of energy would be released if the brakes failed.```
 Subject: Re: E=MC2 simplified From: siliconsamurai-ga on 23 Feb 2005 06:02 PST
 ```Richard, I respect your comment but I believe it is a disservice to the client who probably isn't prepared to really participate in what would be a post graduate-level technical discussion. Remember, this is a question about basic Relativity as stated about 100 years ago, not the latest theories. Understanding Relativity and QM is difficult enough if we just stick to basics, after all, they are only approximations anyway.```
 Subject: Re: E=MC2 simplified From: davidetal1234-ga on 23 Feb 2005 19:27 PST
 ```Gasp! Seems that either you are right, Siliconsamuria GA, about these chemical reactions, or Richard GA is right. The weight of website references is clearly with Richard, but is that the way to the truth? You are adamant that Richard and these websites are wrong. Perhaps the 'way forward' would be to find a site that supports the view that chemical reactions having nothing to do with E=M^C2, perhaps? 'Curiouser and curiouser' cried Alice...:) David```
 Subject: Re: E=MC2 simplified From: xarqi-ga on 23 Feb 2005 20:08 PST
 ```I'm not sure if this will help or not, but here goes. What e=mc^2 does tell us is that any energy has a mass equivalent, so it is true to say that the chemical energy liberated by combustion also has a mass equivalent. It does not however mean that that energy was produced by the conversion of matter into energy. Matter is not the sole medium of exchange of energy, and energy stored in chemical bonds can be liberated as heat without the transformation of matter.```
 Subject: Re: E=MC2 simplified From: ticbol-ga on 24 Feb 2005 03:36 PST
 ```Zeez, I think I am hooked by this E=mc^2 thing again---in its simpler/simplified meaning. I am not a physicist but I love science, especially when I was young. Truly, Physics for physicists/thinkers is mostly about math or calculations. But Physics for us gawkers is also about science---meaning about the whys of the natural/physical things in this the world around us and beyond---about explanations of these whys. Back then I already knew that E=mc^2 is about nuclear physics. My understanding then for energy is about power, for mass is about the total substance or "matter" in a matter, for c is about some very large quantity. Hence, the stored power in any matter is a really very, very big quantity. That is why they worked on atoms only to produce the atomic bomb---otherwise, if they use larger masses, like 5 kilos of steel, they might blow up the earth with the BOMB. Of course as I grew older, and as I gathered from leisurely reading articles about E=mc^2 once in a while as they crossed my path, I learned not to go further in trying to understand fully that equation. Like Mathematics, the more I know about E=mc^2, the more I know less of it---because you are being sucked into the world of luxons, tardyons, gluons, protons, pothons, gluballs, gamma, different meaning/kind of mass, momentum, inertia, quanta, relativity, etc.... It boggles the mind, I always say. Not for my brain, nope. Anyway, E=mc^2 is about the consequence of very big energy from releasing the hold of "whatever-on" on the happy-to-be-separated-but-strapped-to-each-other positive protons in the nucleus of the atoms of radioactive very heavy metals like plutoniom isotopes. (Or from "welding"/forcing-to-combine nuclear particles) Enough force is to be applied, like the initial explosion of the atomic bomb, to release this mind-boggling energy in the resulting splitting/forced-separation of the positive particles in each of the nuclei of some heavy-metal atoms. Can you imagine c^2? It is 300Million times 300Million = 90,000Million-Million of something. About 9*10^16 something! So if they split some atoms of, say, a combined mass of 0.1 kgm, multiplied that by 9*10^16 m^2/sec^2, you'd get about 9*10^15 joules of energy. Looking that up for its equivalence in heat alone, you will understand why Japan surrendered after just two baby atomic bombs...considering that the Japanese didn't know the meaning of surrender before that. Burning, explosions (atomic or not), do not create/destroy mass. Before, during, or after burning or explosions, the mass involved is always constant---the Law of Conservation of Mass. Zeez, who said Physics is easy? Let me maintain/retain what little I understand/think-I-understand about Physics so far. I could be wrong, but its okay. At least I know/think-I-know something about Physics. I can get by when encountering questions like the one above once in a while.```
 Subject: Re: E=MC2 simplified From: amirc10-ga on 24 Feb 2005 13:43 PST
 ```I think that the answers above are confusing and partially misleading. I will try to give a simple explanation. the main idea is: ******************************************************************** The relation between energy and mass is like the relation between a building's height and its shadow's length. The shadow is a projection of the building, and the mass is a projection of the energy. ******************************************************************** This means several things: A. If the sun is at 45 degrees, the shadow's length is always equal to the height, and we can write: l=h, where l is the shadow's length, and h is the building's height. This is equivalent to E=mc^2. B. We cannot convert shadow's length to height or vice versia. We can only change the height, and thus the shadow's length will change. Similarly, WE CANNOT CONVERT ENERGY TO MASS OR VICE VERSIA. C. What we can do, is to take energy from a system, and thus indirectly reduce its mass (i.e., its resistance to acceleration or its gravitation). D. Even in a TNT explosion, chemical energy is passed to the environment, so the TNT after the explosion has less energy than before, and therefore it will have lower mass. THERE IS NO PRINCIPAL DIFFERENCE BETWEEN THIS "MASS-ENERGY" TRANSFORMATION AND WHAT HAPPENS IN A NUCLEAR REACTION. E. In an atomic bomb, the heat energy passed to the world has made the bomb lighter, but MADE THE WORLD HEAVIER. Therefore mass did not "dissapear" or have been "converted" to energy. The source of the energy in this case is the potential of the 'strong force' between the particles. F. Even a particle with no apparent potential energy has a "resting energy", which projects a "resting mass". This resting energy can be transformed to other energy (e.g. in annihilation of an electron and a positron), and therefore the particle will "lose mass" along with losing its resting energy. Again, the energy is passed from place to place, while the mass only "follows' it.```
 Subject: Re: E=MC2 simplified From: siliconsamurai-ga on 25 Feb 2005 07:45 PST
 ```amirc, that is wrong so many ways I don't even know where to begin but- D. Even in a TNT explosion, chemical energy is passed to the environment, so the TNT after the explosion has less energy than before, and therefore it will have lower mass. THERE IS NO PRINCIPAL DIFFERENCE BETWEEN THIS "MASS-ENERGY" TRANSFORMATION AND WHAT HAPPENS IN A NUCLEAR REACTION. Absolute nonsense. there is no TNT after the explosion, the components that made up the TNT have not lost any mass, Here is a common sense way to look at it without even thinking about real physics - if the components had lost mass then, over the past few billion years of chemical reactions the Universe would have completely dissappeared as each reaction caused a loss of mass. E. In an atomic bomb, the heat energy passed to the world has made the bomb lighter, but MADE THE WORLD HEAVIER. Therefore mass did not "dissapear" or have been "converted" to energy. The source of the energy in this case is the potential of the 'strong force' between the particles.. Absolutely, positively, 100% wrong. Energy has no weight or mass so it can't make anything heavier. Your other ideas are similarly incorrect. Your comments show an understanding of science which was prevalent in the 1800's. You appear to be completely misunderstanding all of Physics since about 1890, including conservation of energy. If your ideas were correct then most modern technology wouldn't work. Sorry, please don't take this as a personal attack but I can't let this misinformation pass unchallenged.```
 Subject: Re: E=MC2 simplified From: wolf1728-ga on 25 Feb 2005 16:41 PST
 ```Just thought I'd say thanks again to Google Answers for referencing my website: www.1728.com It's good to know my website is highly regarded. Being cited by Google Answers is confirmation of that. wolf```
 Subject: Re: E=MC2 simplified From: amirc10-ga on 01 Mar 2005 13:37 PST
 ```Dear Siliconsamurai-ga, Although I don't like using that style of expression, I would like to use your first sentence as an opening (only with switching my name with yours, of course). D. Of course "The TNT after the explosion" means "the components that made up the TNT". I thought it was obvious. I hope you didn't seriously think that my intention was that the TNT compound is unchanged (If you did, than I am really insulted?). As for your "common sense" argument: I'm afraid you did not understand my explanation. It does not imply that the universe's mass decreases with a chemical reaction (I really don't know how you concluded this, but maybe I didn't explain myself well). Maybe this will help: Some of the mass of the TNT before the explosion was the projection of its potential chemical energy, but most of it was the projection of the rest energy of its particles. The latter is not changed in the explosion. The former decreases with the decrease in the potential energy, but increases the rest of the world's mass by increasing its energy. Therefore, the total mass of the universe did not change. E. See response to D. I see now that my explanation may not have been as clear as I thought, so I guess you're right about that. It's worth mentioning that I've verified the interpretation presented above with a Physics Dr. . Additionally, In order to minimize future quarrels, I suggest you look at the lecture of Prof. Michael Fowler from University of Virginia, at http://galileo.phys.virginia.edu/classes/252/mass_and_energy.html, which says similar things (e.g., "Give a ballpark estimate of the change in mass of a million tons of TNT on exploding. ... So the change in weight is of order 10-10 x106 tons, about a hundred grams.") You too, please don't take this personally, and let me once again quote you, this time for your fine ending sentence. P.S. Regardless of who's right, a good idea would be to express yourself more cautiously and less confidently in future debates.```
 Subject: And one more thing, From: amirc10-ga on 02 Mar 2005 09:26 PST
 ```Saying that something is "absolutely wrong", "nonsence", "shows no understanding" etc. doesn't make you right. It just makes you more embarrassed when you turn out to be wrong.```
 Subject: Re: E=MC2 simplified From: davidetal1234-ga on 02 Mar 2005 19:26 PST
 ```Amirc10...thank you for your comments. As a result of them I have posted a new question about 'pure energy'. I also agree with the tenor our your comments. An enquiry about E=MC^2 has - after a couple of answers and many comments by several people, finally decended into something of a slanging match. This leaving me (someone with a high school certificate) pretty convinced that no one really understands that formula! There are many possible understandings/beliefs about it and reality remains mysterious, or so it seems. Perhaps it will ever be thus. David```
 Subject: Re: E=MC2 simplified From: siliconsamurai-ga on 07 Mar 2005 12:15 PST
 ```David, I'm sincerely sorry you have been so misled by some comments by people who haven't studied physics for years and who aren't qualified researchers. No, I am not embarrased for actually understanding the past 120 years of physics. Actually a LOT of people thoroughly understand the equation, they are called physicists. Don't be misled by mere comments by people who may have no more qualifications here than a valid e-mail address and one or two comments - that doesn't make them correct. FYI, If anyone is interested, PBS is re-running The Elegant Universe in most areas this week. It can explain a lot of basic cosmology - check your schedules to see if it is airing in your area. Disclaimer - Although I used to work for the station which produces Nova (WGBH), I am no longer affiliated with the station and am simply pointing out that this is an interesting program.```
 Subject: Re: E=MC2 simplified From: donatio-ga on 10 Mar 2005 15:24 PST
 ```Just stumbled across this and thought I could step in to adjudicate :) siliconsamurai's answer is pretty much correct, and I recommend that you use his answer to help you gain your intuitive understanding of what's going on. Nevertheless the others who have commented here including amirc do have a point. I think the problem has arisen because the concept of REST mass hasn't been discussed. Suppose my log has a rest mass of 1 kg which I find out by weighing it on some scales. Then E=mc^2 says that it will have a huge REST energy. Now suppose I throw my log (possibly at a fire) then in CLASSICAL physics (i.e. before einstein) the log has KINETIC energy and it's mass is the same. But modern physics (i.e. relativity) says that the MASS (but not the rest mass) of the log increases (by an incredibly small amount)!!! Using E=mc^2 this means that the energy of my log has increased, and luckily enough the increase in energy is almost the same as the kinetic energy that we used to have in classical physics. So what's all this got to do with burning my log? Well in classical log burning, my log (and the oxygen that we need to use to burn it) would have a mass exactly equal to the masses of all the products of the burning (the smoke the carbon dioxide and the water). The burning process however would give out energy (in the form of heat and light), and this was attributed to some internal chemical energy. Now we want to do modern log burning. Since we're only doing chemistry we'll pretend that atoms are the fundamental building blocks of the universe and we can't find anything smaller. Then each atom will have it's own rest mass. We can think of our log as groups of these atoms "bonded" together. So what's the rest mass of our log? Surely it's the sum of the rest masses of the atoms that make it up? Unfortunately not, there's a tiny little bit extra which effectively represents the classical internal chemical energy. And so in a chemical reaction (such as log burning) NONE of the atoms change their rest mass, but the total mass of the chemicals involved has changed a very tiny bit. The key thing to understand here however is just how tiny all these changes in mass are compared to the rest mass. Have you ever felt heavier while on a fast train journey? Or felt suddenly heavier as your skin absorbed some sunrays? Hopefully the answer to these questions is no. All these forms of energy/mass that we have talked about are absolutely tiny compared to the huge amount of rest energy/mass that makes up the objects we see around us. log burning - a mathematician's revenge```