The sensors that come with our bodies are so limiting. We only hear from 20 Hz to 20kHz, yet acoustic signals cover from the macrosonics, (well below 1Hz), to far ultrasonics (above 2 MHz). Bat sonar is 40kHz – 200kHz. The glass display on your phone uses SAW devices (surface acoustic waves) vibrating at 2 MHz to detect your touch when you text. Can you see the vibration? No. But you use it all the time. (Disclaimer – some phones use capacitive switches. Some use different frequencies. I use it as an example)
I believe in bacteria, viruses, neutrinos, alpha, beta and gamma rays, etc.. I can’t see them but with the help of transducers and electronics I can detect and measure them – and other people can detect and measure them too.
Oops! That neutrino that just zipped through you came form deep space. Oh, and here’s a radio wave from me to you. Now! I just sent an omni-directional 5 GHz electromagnetic pulse out. Within 80ms everyone on the planet just received a little bit of the energy (from my cordless phone).