Create a Ball of Electrons: What Would You See?

[TheTankEngine]

Just something to think about- What if you could make a ball of electrons, maybe a foot thick, and I have no idea how close together. (I don't know how much energy you would need to do this, but I can imagine it's a lot)

The above is just to get a general idea. My question is this: If you looked at it, what would you see? Would you just see straight through it?

 

[falcon32]

Since electrons repulse each other, they would tend to fly apart. Thus, you would never be able to get them in a ball. But for the sake of being hypothetical... :)

Electrons absorb and emit light when they are falling from higher orbitals into lower ones, and vice versa, around atoms. This is why you can see things to begin with. Electrons absorb certain exact wavelengths. They reflect the ones that they do not absorb.

Now take just an electron. Is it orbiting anything? No. So it cannot climb to a higher orbital or fall to a lower one, and thus it cannot absorb or emit the the energy required to make this transition.

So to answer your hypothetical question...(and maybe someone else can comment as well?)...I suspect the ball of electrons would be as clear as air, as light is neither reflected nor absorbed.

 

[m.e.t.a.]

I'm not sure what exactly is meant by a "ball" of electrons "a foot thick", but I take this to mean, "a lot of electrons forced together to occupy a small volume". You could hypothetically trap a large number of electrons using electric and magnetic fields and force them into a small volume. But I am quite sure that the electrons, while trapped, would still absorb and emit light.

In the trapped state, the electrons would undergo frequent accelerations due to their mutual repulsion. The electrons would be "jiggling around" somewhat like the particles of a gas. (But obviously not exactly like the particles of a gas, because gas particles do not repel at long range.)

The accelerating electrons would absorb and emit photons as they transitioned between discrete energy levels within the electron "gas". These discrete energy levels would be so closely spaced as to form a near-continuous band, just like the conduction band available to the electrons of a metal.

At least, this is my best guess! I would not put much trust in what I have said above until this question has been addressed by an expert...

 

[Drakkith]

I'm not an expert, but I am thinking along the same lines as M.E.T.A.

An individual electron free in space can still interact with photons i believe. Having a large amount of them confined to a small area should stil absorb, reflect, or emit light i think.

 

[TheTankEngine]

Haha probably too hypothetical :)

 

[TheTechNoir]

I don't pretend to have a strong understanding of them, so I won't offer much explanation but I will offer a link.

http://hyperphysics.phy-astr.gsu.edu/hbase/solids/coop.html

This is the only way that -I- am aware of being able to bind electrons to one another. It is under a pretty extreme condition too. Very loosely speaking it makes them enter a boson-like state. It's pretty interesting stuff, if you aren't familiar with superconductivity/superfluidity I suggest you research that before cooper pairing.

My guess is that if you had a helium-III superfluid condense into two-atom cooper pairs for a superfluid I would GUESS that you would be able to see the superfluid, though it certainly wouldn't be like the ball or anything that you described and it would be, well, a fluid.

 

[Carrock]

I'm also not an expert, but I think the ball of electrons would behave very like a ball of fully ionised plasma, which can be created or viewed ( eg the sun).

It would be reflective like a low resistance metal.

 

[ZapperZ]

I don't pretend to have a strong understanding of them, so I won't offer much explanation but I will offer a link.

http://hyperphysics.phy-astr.gsu.edu/hbase/solids/coop.html

This is the only way that -I- am aware of being able to bind electrons to one another. It is under a pretty extreme condition too. Very loosely speaking it makes them enter a boson-like state. It's pretty interesting stuff, if you aren't familiar with superconductivity/superfluidity I suggest you research that before cooper pairing.

My guess is that if you had a helium-III superfluid condense into two-atom cooper pairs for a superfluid I would GUESS that you would be able to see the superfluid, though it certainly wouldn't be like the ball or anything that you described and it would be, well, a fluid.

Cooper pair is nothing like a "ball of electrons" the way the OP is seeking. Note also that cooper pairs cannot occur by themselves. They require coupling to a bosonic "glue", such a phonons in conventional superconductors.

The question presented by the OP is a bit odd, mainly because there is a completely disregard of space-charge effects. There is no mention of any kind of mechanism that will hold such a thing together (there isn't). So essentially one is trying to find consequences of something that doesn't occur.

Zz.