This question has been asked before.
Sadly, nobody has answered it.
https://answers.unity.com/questions/1042117/is-posible-make-a-electromagnetic-waves-simulator.html
I am making a game that plays upon the themes of light. I woke up this morning and had a great idea to emulate a radiowave tower and then give players a REAL FM radio in game that players can use to solve puzzles with. I could also give them special goggles that they could use to see the radiowaves. Also, I could use electromagnetic radiation to implement REAL black-lights (not just shaders made to look like black lights). Lastly, I could use electromagnetic radiation to give players infrared goggles.
Does the Unity lighting physics support electromagnetic waves? Or does it just give us RGB? Would something this ambitious be too expensive in terms of CPU/RAM usage?
This is a very specific need, and no, there’s nothing quite like this in Unity. The only thing approaching this is the SoundListener system that allows the simulation of both the speed of sound and the Doppler effect. While it’s close to the issues you have here, it’s a system specialized for a single listener, not millions of pixels.
There’s is no such thing as “real light” in unity. A shader simulating a black light is just as fake as a shader simulating a non-UV light. Unity strays very far from simulating any kinds of physics realistically, and like most engines out there, is just a rough approximation.
Seeing radiowaves is not easy in real-life, as the detector’s resolution is dictated by the wavelength of the radiation. So if you wanted to be realistic, your glasses would need antennas dozens of meter in width. If you don’t care about that, you can simply have multiple types of light that you enable or disable. Using shaders you can simulate fluorescence for black light.
Unity doesn’t just use RGB, but definitely doesn’t use wavelength to describe light, which is neither a performant approach nor an interesting one. Your computer screen couldn’t even display some of the most saturated colors in the real world, no point in computing something that can’t be shown.