Even fusion in stars comes nowhere near to converting matter completely into energy. For hydrogen fusion the figure is something like 0.7% of the mass is turned into energy.
The only way to get close to 100% is direct annihilation of matter with its direct anti-matter equivalent. i.e. to collide protons with anti-protons
This question can be answered only after deep study of concepts hidden in definitions of energy and matter. As per current scientific concept matter is composed of structured arrangement of tiny particles/waves of electromagnetic form of energy (whatever we say electron, proton, neutron, positron etc.). The mystery of electrostatic charge and gravitational field itself is unknown. Interaction among these particles give rise to some form of binding resulting in inertia which is indirect representation of matter or mass. To nullify the inter-particles binding force to disintegrate them to free their capability to perform work (i.e. energy) a separate law of nature needs to be discovered. Young generation may dream in traveling inside the atom in search of this law. But the finding may be disastrous for the humanity as these can be definitely misused.
Primordial matter is is plasma in the Universe. Energy is generated inside Eletric Fields . Gradient Charge potential energy gives mode behavior to the electric plasma like the stars and quasars.
Matter is not converted into energy. Energy is derived from the concentration of electric charges, from the electric field intensity, which generates differentiations of matter according to the movement.
Agree with Mr. Rolaldo view that matter is not converted into energy but what is matter and how we detect it is not very clear. We only detect matter properties such as inertia giving rise to a force. Thus apparently, we may say matter doesn't exist at all and only certain effects such as electrostatic charges effect, inertia effect, gravitational effect, magnetic effect etc. are confined into certain geometrical shape creating different types of configurations i.e. different types of element atom. If algorithm of such configurations are discovered then a particular type of energy stream can be generated and other effects may disappear. Thus feel of existence of matter will vanish. This may create an impression that matter is converted into energy. Regards,
The answer is no. Actually, the only way to convert all of the mass into energy is through matter-antimatter annihilation. But this process is not that common as there is not much antimatter around. So finally, we can say that it is impossible to convert matter completely into energy.
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