Proton Electron Relationship

[Qfwfq]

So protons and electrons can't be created? what about neutrons, can they?

Look up beta decay, weak interactions etc...

[learnin to learn]

Just making sure I understand this. In beta decay, when a a neutron converts to a proton the left over mass changes to kenetic energy?

[Qfwfq]

Uhm, not all of it. You get an electron and a neutrino, these and the proton shoot away from each other.

[CraigD]

Little Bang, if I understand your original question, you’re asking if the total number of protons in the universe is the same as the total number of electrons.

 

I believe the short answer is “about, but not exactly”. (“Why?” is a much more difficult question, having to do with the relative masses of the electron and the Up and Down quarks, and the strength of the strong (gluon) interaction)

 

According to the most widely accepted theory of the history of the universe, the Lambda-Cold Dark Matter or, less formally, the Big Bang model, over time (t), the number of protons (p+), electrons (e-) and their anti-particles (p- and e+) , was, very approximately, something like:

 

t=0 seconds, p+=0, p-=0, e-=0, e+=0;

t=10^-33, p+=0, p-=0, e-=a few, e+=a few;

t=10^-7, p+=0, p-=0, e-=10^89 e+=10^89;

t=10^-6, p+=0, p=0, e-=10^80, e+=very few

t=10^-5, p+=10^80 p-=very few, e-=10^80, e+=very few;

t=10^18 (about now), p+=10^80 p-=0 to very few, e-=10^80, e+=0 to very few.

 

So, for a very brief period, electrons outnumbered protons 10^80+ to none. Now, their numbers are about equal.

 

What’s in store for the far future depends on some still experimentally unproven Physics, but there’s the prevailing scientific guess is something like this:

 

t=10^48, p+=0, p-=0, e-=0, e+=0.

 

Why is e-=0, when, unlike the proton, the electron is fundamental particle, and can’t “decay” into other particles? Because the decay of a single p+ (if it happens – it hasn’t been experimentally observed yet, and theory is vague on it) create photons and a single e+, and an e+ plus an e- = a photon. The far future is predicted to be dominated by photons.

 

See http://en.wikipedia.org/wiki/Timeline_of_the_Big_Bang, http://en.wikipedia.org/wiki/Timeline_of_the_Universe#Long-term_future_for_a_long-lived_Universe and http://en.wikipedia.org/wiki/Standard_model for a more thorough treatment.

 

If you don’t already, I highly recommend you use wikipedia.org for nearly all of you online Physics needs – it’s way better organized than a wide-open search of the whole internet, and can save you much time and confusion.