oh where to start... well I guess I will just take quote's you have posted earlier. These are not even close to all you have said wrong, but it will show how wrong you have been on nearly everything you have said.

gigatons are not a unit of energy. That would be mass or weight depending on what you are talking about.

If you want to say a 21.5 Kt explosion or bomb that is fine, as it is a normal way to explain an explosion and we know it to mean 21.5 Kt of TNT.

21.5 MT of radiation which is none sense that words in that order don't make any sense. I know you are trying to say a 21.5 MT Nuke explosion since you seem to think that means something but all those words say is that the nuclear bomb explosion will be similar to 21.5 MT of TNT. To say 21.5 Nuke explosion or 2,150,000 tons of TNT would be like saying the same thing if you got the numbers right. If it's 21.5 MT that is 21,150,000 tons.

Saying this is a 21.5 MT bomb is the same as saying that this nuke is equivalent to 21.5 MT of TNT. But you think they mean different things because you keep on saying ...21.5 MT Nuke..., or ...2,150,000 ton TNT...

As I show before this the words in that order don't make any sense. 21.5 Megatons of chemical energy... by 2,150,000 tons of exploding TNT... This doesn't make any sense. 21.5 Megatons can be mass or weight it isn't a unit of energy, just read what I said above and hopefully you will understand.

Yes, I completely understand that using a nuke explosion to estimate/explain mass-energy conversion is not exact either in terms of numbers or units used. I also know the standard unit of energy is joule and also that a gram of matter has 9.0×10^13 J whereas the yield of the fatman nuke (21.5KT rated) was 8.8×10^13 J.

Why did I do this? I did that for simplicity and also in a direct way of extending the original point above i.e. in the highest sense, the units and structures do not matter by themselves i.e there are limitless ways to express mass-energy equivalents. I used the nuke explosion primarily to ensure the average reader understands the scale of things which I was talking about here.

The average reader may most probably not immediately understand the implications of one gram of matter expressed in joules i.e 9.0 x 10^13 J. But when I say it is an equivalent of a 21.5 KT nuke explosion, he will immediately know it will ruin his day for good. When I say 21.5 KT nuke explosion for a gram, he knows it will fuck up his city, when it is 21.5 MT for a KG, he knows it will fuck with his state, when it is a 21.5 GT for a ton, he definitely knows his country is not going to look pretty after that. So my using this nuke explosion as a model for matter conversion was simply a convenient tool to help the reader understand and get the picture of the scale of things. And no, it was not wrong, just unorthodox, a conceptual convenience . You give me lack for merely using the non standard unit for mass-energy conversion, surely I deserve it, but I gave the reasons for the same and you are guilty of a much greater crime, inventing fantasies to prove your point as I shall explain below.

It is Rest mass that is used in the e = sqrt((m*c^2)^2 + (pc)^2) equation.

Rest Mass is the only real mass people care about, relativistic mass is something physicist avoid using as it adds to confusion. Lets say I am on a spaceship that has an engine that can accelerate at 10m/s^2 and doesn't use any fuel. I start accelerating away from you at 10 m/s^2. I have an accelerometer on my spaceship. I could accelerate away from you for as long as I wanted and my accelerometer would always read 10 m/s^2. The mass of my spaceship would always be the same, the speed we are moving away from each other will always be less than the speed of light. On the spaceship everything would seem just the same as when the voyage started.

Lets say you wanted to calculate how much energy the mass of my ship is equivalent to. You use the Rest mass, if you were to use the relativistic mass you would get totally wrong results.

http://physicsandphysicists.blogspot.com/2009/04/rest-mass-versus-relativistic-mass.html
In real life everything is and isn't moving it just depends on the frame of reference. In my frame of reference I am not moving, neither is my house, computer,...

Err what? A spaceship which is fueled by nothing, but your fantasies? What did I say earlier? I said rest mass is used for a calculation convenience as opposed to you saying physicist use real mass to avoid confusion. Whats the difference? If I join your statement with mine. I get this:

Physicists use real mass for calculation convenience.

I already said the rest mass is the summation of all the masses of the individual, discrete units of matter within. I never debated this, I only claimed the value is still inaccurate and needs to be continuously measured. Do you really think the absolute rest masses (i.e latent energy within a standard structural unit of matter) have been found? No, it has not been so. Read this if you want, they were still measuring the proton's mass last in 2007-08. I don't think they will ever stop.

The internal dynamics of the proton are complicated, because they are determined by the quarks' exchanging gluons, and interacting with various vacuum condensates. Lattice QCD provides a way of calculating the mass of the proton directly from the theory to any accuracy, in principle. The most recent calculations[9][10] claim that the mass is determined to better than 4% accuracy, even to 1% accuracy (see Figure S5 in Dürr et al.[10]).

** These claims are still controversial, because the calculations cannot yet be done with quarks as light as they are in the real world **. This means that the predictions are found by a process of extrapolation, which can introduce systematic errors.[11] It is hard to tell whether these errors are controlled properly, because the quantities that are compared to experiment are the masses of the hadrons, which are known in advance.

These recent calculations are performed by massive supercomputers, and, as noted by Boffi and Pasquini: "a detailed description of the nucleon structure is still missing because ... long-distance behavior requires a nonperturbative and/or numerical treatment..."[12] More conceptual approaches to the structure of the proton are: the topological soliton approach originally due to Tony Skyrme and the more accurate AdS/QCD approach that extends it to include a string theory of gluons, various QCD-inspired models like the bag model and the constituent quark model, which were popular in the 1980s, and the SVZ sum rules, which allow for rough approximate mass calculations. These methods do not have the same accuracy as the more brute-force lattice QCD methods, at least not yet.

http://en.wikipedia.org/wiki/Proton#cite_note-Fodor-9

This is the exact point I have been stating. I never said the mass of the proton cannot be found. My original claim was and remains that such natural physical values will force us to make continuous observation of the same with better and better instruments. You didn't need that ridiculous example to make that point. Any two proton in the universe will have its rest mass as the same because of its structural aspect remaining the same anywhere in the universe.

I say it again: Rest mass is the same for all classes of matter, but only approximate yet. Relativistic matter is the 'truth' of the physical reality outside our calculations. But even a computed relativistic mass will still be approximate if done by us. The objective truth of reality can be gain only through continuous measurements with increasing accuracy.

Now you also used the speed of light in your fantasy example as a bid to make some point, but do you really understand the implications of mass-energy conversion law. Your own example gets tripped by the very link you posted. I will bring up the exact point in that article, the reason how you misunderstood mass-energy equivalence.

Einstein's tolerance of E=mc^2 is related to the fact that he never used in his writings the basic equation of relativity theory. However, in 1948 he forcefully warned against the concept of mass increasing with velocity. Unfortunately this warning was ignored. The formula E=mc^2, the concept relativistic mass, and the term rest mass are widely used even in the recent popular science literature, and thus create serious stumbling blocks for beginners in relativity.

Here is the proper info about this:

The law of conservation of mass, also known as the principle of mass/matter conservation, states that the mass of an isolated system (closed to all transfers of matter and energy)

The concepts of both matter and mass conservation are widely used in many fields such as chemistry, mechanics, and fluid dynamics. Historically, the principle of mass conservation, discovered in chemical reactions by Antoine Lavoisier in the late 18th century, was of crucial importance in progressing from alchemy to the modern natural science of chemistry.

**In a thermodynamically closed system (i.e. one which is closed to exchanges of matter, but open to small exchanges of non-material energy (such as heat and work) with the surroundings) mass is only approximately conserved.** In this case the input or output of energy changes the mass of the system, according to special relativity, although the change is usually small since relatively large amounts of energy are equivalent to only a small amount of mass.

**Mass is absolutely conserved in so-called isolated systems, i.e. those completely isolated from all exchanges with the environment **. In special relativity, the mass-energy equivalence theorem states that mass conservation is equivalent to total energy conservation, which is the first law of thermodynamics. [/B] In special relativity the difference between closed and isolated systems becomes important, since conservation of mass is strictly and perfectly upheld only for isolated systems. In special relativity, mass is not converted to energy, as such, since energy always retains its equivalent amount of mass within any isolated system. However, certain types of matter may be converted to energy, so long as the mass of the system is unchanged in the process. When this energy is removed from systems, they lose mass. [/B]

**In general relativity, **mass (and energy) conservation in expanding volumes of space is a complex concept, subject to different definitions, and neither mass nor energy is as strictly and simply conserved as is the case in special relativity and in Minkowski space.

http://en.wikipedia.org/wiki/Conservation_of_mass

Now if you can understand what Einstein said in your own link and the points I bolded in my link, the implications means that unless you invent a way for feasible propellantless propulsion, your spaceship is bound to lose MATTER as it accelerates forward. The energy the expelled propellant imparts to you is your acceleration, but then even if there is an hypothetical propellantless engine, then you will need somekind of engine uses a nuclear or antimatter source which still means mass loss.

Now if you use some kind of external force to power your momentum, it will still impact the mass of your ship due to perhaps elegant or/and gentle degradation which at some point of time will destroy your ship eventually (thus making it lose mass.) If you use gravity, then perhaps your means of acceleration is unlimited, but your journey usually ends with a loud splat on the surface of the source of that gravitational field sooner or later. To avoid this, you will need something to steer your ship which again means fuel and you can guess the next.

Please do not invent fantasy fallacious examples to try prove a point. You end up hurting yourself.