Do we really need virtual particles to exist?

I understand the $\Delta t \cdot \Delta E \geq \hbar / 2$ relationship and the idea behind them. However, I don't understand why do we need them at all. I'm a physics undergraduate. As far as I know, all the physics equations I'm dealing with doesn't involve virtual particles at all. So why do we need them if we can get to the correct answers without them anyway?

I have read around some related questions to this (not exactly the same questions though). I believe it was pointed out that we need virtual particles for some mathematical model, but why do we call it "virtual particle"? I think we should call it force or field (a new type of force or field; something like that for example). Another point is why do we need that model in the first place if the model without virtual model works just as well? Thank you!

• 1. If you think the "energy-time uncertainty relation" has anything to do with virtual particles, you understand neither, and have fallen prey to a popular, but false, interpretation. See this question for what the energy-time uncertainty actually means. 2. What do you mean by "what do we need them for"? We don't, as you say you can get every result without ever talking about them, since they are just fancy names for lines in a diagram. Commented Nov 30, 2015 at 23:22
• Well, virtual particles are allowed exist is exactly due to that inequality as far as I know. Anyway, you're saying we don't need them? What I don't understand is if we don't need them then why did anyone bother to come up with the entire new concept of "virtual particle" plus new "fancy" math behind it? Commented Nov 30, 2015 at 23:42
• A short introduction to a different view about electric field excange I give here academia.edu/11805855/Are_photons_composed_particles, the longer one ist availible only in German academia.edu/12172263/…. Commented Dec 2, 2015 at 5:21
• The English version "Complex one-dimensional structures of space" is now available academia.edu/19657550/… Commented Jan 17, 2016 at 18:45