Is there any known ways in Physics how to convert Red light to blue?
Upconversion, for example. Your question is very vague. Where does the red light come from and what do you want to do with the blue light?
Any possible light source.
Does "let the light shine on a photovoltaic cell, use the electricity to operate a source of blue light" count as well?
What about growing plants with red light, burning them in a power plant and operating a light source with it?
You see how vague the question is?
Can we keep the applications private. An effortless conversion is always best.
Get in a spaceship, travel away from earth, then turn around and travel toward it at high speed.
Sound absurd? Without knowing the constraints, that's all we can do. This type of free-form, idle speculation is not useful. Thread locked.
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