# Nuclear fusion and strong force

If this blob has less mass=energy than the two original nuclei had separately, the excess energy will be released, and we'll end up with a single new nucleus (at least for a time). Fusion accomplished.

the excess of energy released would be from which source? i mean to say which form of energy would be compromised and released in fusion?

Staff Emeritus
2019 Award
that depends on how strongly they repel doesnt it? And the nuclear force is pretty darn strong.
That's one of the weakest defenses of incorrect physics that I have seen. "Pretty darn strong"?

If you have a potential barrier U, no matter how large or how small, you need a kinetic energy T (T >= U) to overcome it. "Pretty darn strong" has no effect on the qualitative behavior.

humsafar said:
I want to know the work of strong force during fusion of two atoms (say hydrogen), It is known that atoms need to get close enough to fuse but what does strong force especially "color charges" or "gluon" perform which causes fusion?

The excess of energy released would be from which source? i mean to say which form of energy would be compromised and released in fusion?

Wikipedia said:
The nuclear force (or nucleon-nucleon interaction or residual strong force) is the force between two or more nucleons. It is responsible for binding of protons and neutrons into atomic nuclei.

In 1934, Hideki Yukawa made the earliest attempt to explain the nature of the nuclear force. According to his theory, massive bosons (mesons) mediate the interaction between two nucleons. Although, in light of QCD, meson theory is no longer perceived as fundamental, the meson-exchange concept (where hadrons are treated as elementary particles) continues to represent the best working model for a quantitative NN potential.

Two-nucleon systems such as the deuteron, the nucleus of a deuterium atom, as well as proton-proton or neutron-proton scattering are ideal for studying the NN force. Such systems can be described by attributing a potential (such as the Yukawa potential) to the nucleons and using the potentials in a Schrödinger equation. The form of the potential is derived phenomenologically, although for the long-range interaction, meson-exchange theories help to construct the potential. The parameters of the potential are determined by fitting to experimental data such as the deuteron binding energy or NN elastic scattering cross sections (or, equivalently in this context, so-called NN phase shifts).

The most widely used NN potentials are the Paris potential, the Argonne AV18 potential, the CD-Bonn potential and the Nijmegen potentials.

The energy released in most nuclear reactions is much larger than that in chemical reactions, because the binding energy that holds a nucleus together is far greater than the energy that holds electrons to a nucleus. For example, the ionization energy gained by adding an electron to a hydrogen nucleus is 13.6 eV—less than one-millionth of the 17 MeV released in the deuterium–tritium (D–T) reaction shown in the diagram to the right. Fusion reactions have an energy density many times greater than nuclear fission; the reactions produce far greater energies per unit of mass even though individual fission reactions are generally much more energetic than individual fusion ones, which are themselves millions of times more energetic than chemical reactions. Only direct conversion of mass into energy, such as that caused by the collision of matter and antimatter, is more energetic per unit of mass than nuclear fusion.
Nuclear Fusion is mediated by massive bosons (mesons) particles called neutral pions that mediate the interaction between two nucleons. However, because the nuclear reaction is residual, it is not considered to be a fundamental nuclear reaction.

$$p + n \rightarrow^{\pi^0} D + \gamma(2.224 \; \text{MeV})$$

More specifically it is the result of the residual nuclear force between two Baryon particles that is described by Quantum Chromodynamics (QCD) and is modeled on what is called an NN-potential.

The energy released in nuclear fusion is the result of the release of the nucleus nuclear binding energy.

The nuclear binding energy is the amount of energy required to completely dissociate all the nuclear particles in a compound nucleus.

Reference:
http://en.wikipedia.org/wiki/Nuclear_force" [Broken]
http://en.wikipedia.org/wiki/Nuclear_fusion" [Broken]
http://en.wikipedia.org/wiki/Baryon" [Broken]
http://en.wikipedia.org/wiki/Meson" [Broken]

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Just one more thing......
After big bang, there was quark-gluon plasma as first matter which later formed to hadrons, the strong force is associated with gluon but where does electromagnetism came in hadrons from when quark-gluon plasma formed hadrons

Just one more thing......
After big bang, there was quark-gluon plasma as first matter which later formed to hadrons, the strong force is associated with gluon but where does electromagnetism came in hadrons from when quark-gluon plasma formed hadrons
You probably need to try and rephrase this. I think your question is how do E&M forces enter into a hadron that is formed from strong forces (in particular that comes from a quark gluon plasma)?

Is there any particle in nature besides neutron which is electromagnetically neutral?

Is there any particle in nature besides neutron which is electromagnetically neutral?
Yes, oodles of them.

Drakkith
Staff Emeritus
If my understanding is correct, then:
An anti-proton and a proton would attract each other very easily since they are opposite charges. This would pull them together and the strong nuclear force would take over once they were close enough to each other, and soon after they would annihilate each other.

Also, in regards to the OP, the strong nuclear force is the driving force behind fusion. Once the particles get close enough for the strong force to overcome the repulsion of the electromagnetic force, the two particles would bind together.

Gluons are to the strong force like photons are to the electromagnetic force. They both "mediate" their respective forces. The attraction or repulsion of an electromagnetic source (Magnet/charged particle) is thought to be caused by an exchange of Photons. In a similar way, the attraction of the strong force is due to the exchange of Gluons between quarks.

That help at all?

Gluons are to the strong force like photons are to the electromagnetic force. They both "mediate" their respective forces. The attraction or repulsion of an electromagnetic source (Magnet/charged particle) is thought to be caused by an exchange of Photons. In a similar way, the attraction of the strong force is due to the exchange of Gluons between quarks.
And a nice thing to remember about these "exchange" particles is that the force they mediate is inversely proportional to the mass of the particles themselves. This is why gravity and the electromagnetic forces have an infinite range as gravitons and photons are seen to have zero mass. Whereas a force such as the weak force is short-ranged because the exchange particles which mediate them are massive W and Z bosons.

Incidently a Z boson is another example of a charge neutral particle.

From what I can tell though, the strong force which acts between quarks, mediated by gluons does not diminish with range, however once outside the hadron which the quarks compile the strong force observed between hadrons is a residuum of this, and at which point these gluons contribute to the rho and pi mesons which act as the exchange particles between nucleons. These particles have mass and so explains partly why the strong force between nucleons has a short range.

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does neutralino have its antiparticle?