Are the variables in E=MC2 transposable?

Question

I am curious if M=EC2 is a valid formula as well. If true this would tell me how much energy is needed to create matter. If we extrapolate even further it would tell us how much "energy" there is in the universe based upon the estimates of matter in the known universe. Taking into account the law of entropy and general theories of residual energy loss we can work backwards towards the creation of the universe in knowing how much "energy" was needed to create said universe. This would be helpful to mankind as a whole in figuring out how long until the universe resets itself. If you've followed me this far just one more theory. If all the matter in the universe is gathered in one mass as the law of thermodynamics states it will be, then energy will be created by the tremendous forces and pressures of such an event. We could be in any number of a cycle of a repeating system. Of course this is all very vague and I have no clinical data to support such wild flights of fancy.

Answer 1

This is exactly what is done by cosmologists, though using formulae that go very well beyond the E=mc^2 of special relativity (most especially the field equations of the theory of general relativity). The main problem with these calculations at present is that based on the observed movement of stars and galaxies there is not enough observed mass in the universe to explain what is going on. This means it is not possible to forecast what happened at the beginning of the universe yet by extrapolating back. Whats more, in the early universe, matter and energy were so concentrated that the laws of quantum mechanics that apply to very small things like atoms simply break down as well.

However, you are confused over the role of thermodynamics. There is no such thing as "residual energy loss" - mass/energy is always assumed to be conserved. And entropy does not directly factor into the laws of general realticity (and has nothing to do with E=mc^2).

But entropy is important. Entropy is a measure of the number of possible states a system can be in. Things happen in the universe not because energy is used up (it is always conserved remember) but because the universe moves to a situation where it uses up more possible states (this is like saying that there is only one way to solve a jigsaw but lots of unsolved states - so starting from now the likelihood is that the jigsaw will get less solved). Extrapolating this back, you have to conclude that the early universe was a very special state of very low entropy. It is not known precisely why this is the case, and it is now thought that there is no way to reverse entropy (Steven Hawking took a different view on this for a while, but has revised it) - so it is not clear you can repeat the big bang because you could never reduce the entropy of the universe sufficiently.

Answer 2

gee Rob, know nothing about algebra?

you cannot "transpose" variables like that?!

the equation ALREADY tells you how much energy is needed to create matter. Take the mass of the matter you want to create, multiply by the square of the speed of light, and you get how much energy you'd need (which is a LOT).

take the current estimated mass of the universe (look up on the Web), and you can see how much energy this would represent.

if you want to have the mass, m, alone on one side of the equation, then you need to divide both sides by c^2, which gives you:
m=E/c^2

which you would interprete as, with a given energy E, how much mass can I create (and that's very little, for most reasonable amounts of energy).

as for going back in time and calculating how long ago the universe started, this has already been done, mostly from the expansion speed, and I don't see where knowing how much energy there is (which we know already, since energy and mass are the same thing), will help.

no, energy does not "get created" by the tremendous forces and pressures of the contraction of the universe. For example the sun has contracted initially, and this generated heat in its core, but it didn't come for free - no net energy was created.


You know what? You sound very enthusiastic, which is great. But you also sound like you've got very superficial knowledge of stuff such as thermodynamics, one formula taken out of context and which you don't seem to understand, etc.

What I suggest? Given your enthusiasm, and assuming you're quite young still (I'm betting on this given that you don't seem to know any algebra), then I'd HIGHLY RECOMMEND for you to study physics, you might enjoy it a LOT. And when you've learned much more stuff, who knows, maybe you'll be the guy who can tell us WHY all this is here?

good luck

Answer 3

You have put Einstein's mass-energy relationship wrong. The correct relationship is; E = m*c^2
where m is the mass of the object, c is the speed of light in free space, which by the way is a constant.
Just to give you an idea of much energy a kilogram of mass contains lets use Einstein's formula and calculate the energy:
E = 1kg*(3x10^8m/s^2
E = 9x10^16J
Now you know why a nuclear bomb is so destructive even though it converts only a fraction of its total mass to energy.

Estimates of the total matter content are still hazy because of the presence of "dark matter". So the energy requirements for the Big-Bang creation could be worked out in principle. But there are other subtle effects which you have to take into account.

Answer 4

It's even easier than all your answers so far ! The speed of light is a constant so you can remove it from the equation completely so it becomes E=M , its that simple and emphasises beautifully that energy and mass are the same thing. C^2 is put in to make the units for mass easier to handle.It also serves to highlight that you get a lot (a whopping amount actually) of energy for a little bit of mass.

As for the energy content of the universe - we know that already. The net energy is zero ! Absolutely zilch. It comes about because gravitational energy is negative and exactly cancels out all the "normal" energy. At the moment the universe is "out of balance" so to speak .

Answer 5

E=obama M=american C=idiot squared

Answer 6

Well no, e = mc^2, so m = e/c^2, but that certainly is true.