> You should have understood that I meant otherwise. Of course, if we could notice the effect of EM, that could trigger an investigation eventually leading to the discovery.

Can you suggest an environment conducive to life that isn't exposed to EM radiation? Life itself creates EM radiation.

> When I meant sensory capabilities I meant the stuff we can sense, directly or indirectly (By indirectly, I mean by the help of another device, to make it very clear).

I can't prove God doesn't exist either, but that doesn't make it logical to conclude that we will one day be able to harness the power of God for FTL communications, but this is what you're expecting. If there are fundamental forces left to be discovered then they are not having any observable effect on the world, making them unlike all other fundamental forces. This makes them unlikely to ever be discovered.