You can open the link given just below to view the proof that prove that E=mc

^{2}is not valid. The proof is based on simple calculus and some fundamentals of physics.The content shown on the link just below might clear your doubts regarding the integration constant that should be introduced in the result of integration obtained in the content given on the link mentioned just above.

Updated proof that E=mc

You can also open the link given just below. The content given on the link given just below includes derivation of relationship between energy, mass and velocity using vector algebra and calculus. It is more general than the proofs given on the links shown above because more general method is employed in deriving it and it may clear your doubts regarding whether the results obtained in the proofs given on the links shown above are general results or not.

^{2}is not valid as a general equationYou can also open the link given just below. The content given on the link given just below includes derivation of relationship between energy, mass and velocity using vector algebra and calculus. It is more general than the proofs given on the links shown above because more general method is employed in deriving it and it may clear your doubts regarding whether the results obtained in the proofs given on the links shown above are general results or not.

Here it should be noted that the proofs given on the links shown above need to be evaluated and examined critically and they should be accepted only after critical evaluation or examination by experts.

In the end, you can open the link given just below to view the content which tries to refute energy mass equivalence using logical arguments.