Thanks, just read it. Unfortunately I think the question seemed to be treated with a bit of harshness in the responses and it died too quickly because of this.
'Fields' are mathematical constructs, nothing more in my opinion. What is the nature of the field? What is it made of? How does it transmit a force?
I don't buy into the idea of gauge bosons or virtual particles either. Again mathematical constructs to describe behaviour, not reveal the true nature of things.
It's been proved that light can transmit force to a mass. Light is an EM wave? Or a photon? What is a wave really? What is a photon really?
Sorry if this whole area makes difficult discussion. I believe that modern physics is inventing ever increasingly complex mathematical models for the true nature of matter, but I think in reality is probably getting further and further away from the real answer.