Simon Wrote:
-------------------------------------------------------
> Hi Bernard
>
> bernard Wrote:
> --------------------------------------------------
> -----
> > You have to deal with the real world here and
> not
> > just the mathematics. The electrons in an
> atom do
> > not exist alone. The possible "n's" have to
> do
> > with the number of protons in the nucleus
> thus
> > you cannot have an atom with zero protons
> much
> > less with a minus proton (whatever that
> would
> > be!)
>
> Ah okay so you can have isotopes but you always
> need a balance between electrons and protons ?
Isotopes have the same number of protons (therefore the same element) but different numbers of neutrons. To have a neutral atom you have to have the same number of electrons and protons.

> You see this is where I get a little confused
> about the reason for this. I mean if its just
> that balancing of the charges between the protons
> and the electrons then why do the protons stick
> together ? Why is there such a strong force that
> only acts to hold protons together ?

Again some basics so that we all are on the same page. Thre are 4 forces (going from weak to strong): gravity, weak force; electromagnetic; strong force. There are force carrying particles associated with each: graviton (postulated but not yet seen); W and Z bosons; photons; gluons. The forces differ in strength: if strong = 1; electromagnetic is 10^-2; weak is 10^-5; and gravity 10^-41 and they differ in effective range (in meters); strong =10^-15; electromagnetic = infinite; weak =10^-18; gravity = infinite.

Thus protons and electrons are held together by the electromagnetic force. Apart from the fact that each of these forces acts only on certain things 1) the elctrons are too far from the nucleus for the strong force to reach and 2) the strong force is 100 times more than is needed to hold the electrons.

A wonderful book to read is Don Lincoln. 2004. Understanding the Universe from Quarks to the Cosmos{/u} London:World Scientific


Why couldn't
> gluons by themselves in the absense of proton
> quarks hold electrons in a shell where n is
> negative ?
>
>
>
> ----
>
>

Bernard
> Simon
>
> InternalSpace