# How the nuclear binding energy gives mass to the nucleus?

Hello everybody! I have some difficulties concerning the concept of nuclear binding energy.
First, look at this example:
In the first case, the two protons have big energy. But this energy is not changing it's weight. And in the second case, when they collided, the energy that they contained transformed to new particles, so more mass.
But in the nuclear binding energy, when this energy converts into mass?

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Astronuc
Staff Emeritus
The example seems to be one of particle production rather than nuclear binding energy.

On the left side, the initial (rest?) mass is 0.3 unit, and on the right side one has 9 tracks, which are ostensibly particles and the total rest mass is now 1 unit. So the unknown or unspecified kinetic energy has been transformed into rest mass. It's not clear if the new particles are stable however.

Yes, but my question is when the energy of the proton converts to mass an how? We are speaking about the nuclear-binding energy.

mfb
Mentor
For high-energetic particle collisions, nuclear binding energy is not relevant. You convert the kinetic energy of particles to mass of new particles.

"How": quantum field theory. It just happens, and theories can calculate the probabilities. There is no fundamental "reason" or "process" why/how it happens.

For high-energetic particle collisions, nuclear binding energy is not relevant. You convert the kinetic energy of particles to mass of new particles.

"How": quantum field theory. It just happens, and theories can calculate the probabilities. There is no fundamental "reason" or "process" why/how it happens.
We know that it happens but then the theory is incomplete since it can't explain how it happens.

mfb
Mentor
The theory is not incomplete.
It is physics, not philosophy.
The theory can give you a model "how" it happens, it does not care if it is "real" (whatever that means).

Bill_K