How could it be proven that E=mc²?

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While developing special relativity, Einsteen found that:
KE = [m0*c² / √(1 - (v²/c²))] - m0*c²
where m0 is rest mass.

He included the second term on the right to make sure that for small velocities, the energy would be the same as in classical mechanics:
KE = (1/2)(m0*v²) + ...

Without this second term, there would be an additional contribution in the energy when the particle is not moving.

Einstein found that the total momentum of a moving particle is:
P = [m0*v / √(1 - (v²/c²))]

The ratio of the momentum to the velocity is the relativistic mass, m:
m = [m0 / √(1 - (v²/c²))

And the relativistic mass and the relativistic kinetic energy are related by the formula:
KE = mc² - m0*c²

Einstein wanted to omit the unnatural second term on the right-hand side, whose only purpose is to make the energy at rest zero, and to declare that the particle has a total energy which obeys:
E = mc²

This total energy is mathematically more elegant, and fits better with the momentum in relativity. But to come to this conclusion, Einstein needed to think carefully about collisions. This expression for the energy implied that matter at rest has a huge amount of energy, and it is not clear whether this energy is physically real, or just a mathematical artifact with no physical meaning....Show more

Energy and mass are equivalent

According to the conventional model of particle physics, protons and neutrons comprise smaller particles known as quarks, which in turn are bound by gluons.

The odd thing is this: the mass of gluons is zero and the mass of quarks is only five percent. Where, therefore, is the missing 95 per cent?

The answer, according to the study published in the U.S. journal Science today, comes from the energy from the movements and interactions of quarks and gluons.

In other words, energy and mass are equivalent, as Einstein proposed in his Special Theory of Relativity in 1905. The e=mc2 formula shows that mass can be converted into energy, and energy can be converted into mass.

Last year a different stream of evidence from particle accelerators also corroborated the theory (see, Einstein is still right on time). Yet another study of pulsars backed-up Einstein's General Theory of Relativity in 2006 (see, The stars say Einstein was 99.95 per cent right).

Inspiration for atomic weapons

By showing how much energy would be released if a certain amount of mass were to be converted into energy, the equation has been used many times, most famously as the inspirational basis for building atomic weapons.

But resolving e=mc2 at the scale of sub-atomic particles – in equations called quantum chromodynamics – has been fiendishly difficult.

"Until now, this has been a hypothesis," France's National Centre for Scientific Research (CNRS) said proudly in a press release. "It has now been corroborated for the first time."

For those keen to know more: the computations involve "envisioning space and time as part of a four-dimensional crystal lattice, with discrete points spaced along columns and rows."

for more info go to physorg.com...Show more