What is an electrostatic/Coulomb barrier? How is it created?

[smartypants123]

I learned that for nuclear fusion to take place, particles must overcome the electrostatic field but what exactly is it? And how is it created/formed?

 

[Nugatory]

It's pretty simple stuff. Unlike charges attract but like charges repel. The particles that we're fusing (atomic nuclei) are positively charged so they naturally repel one another; to fuse them we have to force them together ("push them through the Coulomb barrier").

The electrostatic field is the field that surrounds a charged particle and attracts particles with one charge and repels particles with the other charge. It's pretty much analogous to the gravitational field that surrounds the Earth and pulls things towards the earth; the only big difference is that the gravitational field happens to always attract.

 

[ZapperZ]

This is an illustration of what Nugatory was describing:

Zz.

 

[smartypants123]

It's pretty simple stuff. Unlike charges attract but like charges repel. The particles that we're fusing (atomic nuclei) are positively charged so they naturally repel one another; to fuse them we have to force them together ("push them through the Coulomb barrier").

The electrostatic field is the field that surrounds a charged particle and attracts particles with one charge and repels particles with the other charge. It's pretty much analogous to the gravitational field that surrounds the Earth and pulls things towards the earth; the only big difference is that the gravitational field happens to always attract.

Well that kinda gives me a new question: I'm assuming this electromagnetic field applies to magnets as well, so why is it that I can touch two magnets that repel each other and break the electrostatic field but for the nuclear fusion particles it wouldn't be so easy? Why is the electrostatic field stronger with those individual particles? Does it depend on the amount of energy they have?

 

[RaamGeneral]

If you take two protons there are two different forces between them: one is the long range repelling electrostatic force [every charged particle, like a proton, produces an electric force onto every other charged particles], the other is the very short range "strong interaction" that binds the two particles together. So you need to push the two protons close enough (overcoming the repulsive force) in order for the strong interaction to fuse them together.