When energy converts to mass, how does energy stay together and form mass (substance) ?

Question

Mass <==================> Energy
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Atom <=> (protons, neutrons) <=> quak <=> ? (string)

Answer 1

In classical Physics, if a particle of mass m is moving with a speed v, then it is said to possess a kinetic energy of 0.5 m v v.

Thus a mass having a speed v has some kinetic energy. The energy stays together with the mass.

By the theory of relativity, the old concept of mass has changed. The earlier concept of mass is valid only when an object is at rest.

Now we know when a particle is moving with certain speed its mass increases.
This is contradictory to our concept of mass. Our earlier concept of mass makes us think that something is added to the mass.

In fact what is not changing is the rest mass of the particle. When a particle is moving its kinetic energy increases. If we use the earlier formula of 0.5 m v v, there is no limit to the speed of the particle and it is not affected by the speed of light.
As it is proved that the light’s speed is constant, we cannot make the kinetic energy of any particle more than the value m cc.

The above fact made us discard the formula 0.5 m v v for kinetic energy calculation and a new formula, namely “increase in mass x cc”.

This has lead to the fact that mass and energy are different forms of energy.

The mass of a particle when it is rest is the mass referred in classical physics and it can be thought of energy of m0 cc. When the mass is moving with a speed v, its internal energy is m0 cc and its kinetic energy is “increase in mass x cc”.

One has to think the “increase in mass” as the property of the particle and not as an increase of MATTER.

Mass and MATTER are different. In classical physics they were inseparable from each other.

Now a matter possesses mass and the minimum mass is when it is at rest and it increases with speed. The increase in mass denotes the increase in its kinetic energy or some form of energy.

Answer 2

As far as I know the only way available to convert energy into mass is to use a particle accelerator, which is sort of a reverse nuclear power plant. It pulls electric power from a grid, just like your vacuum cleaner. I don't think that energy just stays together per say.

Answer 3

Look up the Bethe cycle. When the sun fuses hydrogen into helium, some of the energy is used to bind together the nucleus (two neutrons, two protons). You'd expect the protons to repel each other due to their like charges, and they do. But the nuclear interactive forces prevent them flying apart. Protons and neutrons are approximately the same mass. But four hydrogen atoms (four electrons, four protons) fusing liberate more energy than is needed to make one helium atom (two electrons, two protons, two neutrons).