I learned 2 things:
A salt bridge is necessary in a galvanic cell so charge does not build up in the halfcells countering the potential difference created by the separate redox pairs. Indeed, this would stop the flow of electrons eventually.
The potential of the galvanic cell depends on the concentrations of ions of both redox pairs through the Nernst equation.
Now looking up the salt bridge on Wikipedia, I get 'It maintains electrical neutrality within the internal circuit, preventing the cell from rapidly running its reaction to equilibrium.'
So if the salt bridge influences the equilibrium, it must affect the Nernst equation, I was wondering how you could work this in the equation? Is the original Nernst valid when the salt bridge is there? And how do you write it in absence of the salt bridge?