I am exploring a fundamental question at the intersection of photobiology, neuroscience, biophysics, optical communication, and information theory.
If light can be deliberately modulated to carry information in Li-Fi, what fundamentally changes when the receiver is biological rather than electronic?
In Li-Fi, information is encoded into a light signal by deliberately changing measurable properties of the light, such as intensity or other characteristics. A photodetector detects these changes and reconstructs the encoded information.
This raises an interesting question for biological systems. Photoreceptor molecules can detect photons, and light can produce measurable biochemical changes in biological tissue. But can these changes be used not merely to detect the presence, intensity, or wavelength of light, but to transmit a deliberately encoded information pattern into a biological system?
I am particularly interested in distinguishing two concepts:
1. Light as information about a source
The physical state of a source naturally produces a pattern of light, and the receiver extracts information about the source from that pattern.
2. Light as an information carrier
An independent message is deliberately encoded into a light signal, transmitted through space, detected by a receiver, and decoded.
Li-Fi clearly demonstrates the second concept with electronic receivers. My question is whether biological systems have mechanisms that could perform an analogous process, even at a very basic level.
For example, could a temporally structured sequence of photons, wavelengths, intensities, polarization states, or other optical parameters produce a corresponding structured sequence of molecular or cellular states in a biological receiver?
I am not assuming that this is currently possible, and I am not proposing that complex knowledge such as language or skills can presently be “downloaded” into the human body through light. I am trying to identify the scientific boundary between what is already demonstrated and what remains unknown.
I would particularly appreciate input from researchers working in photobiology, optogenetics, neuroscience, biophysics, optical communications, information theory, and molecular signaling.
My central question is:
What are the known physical and biological limits on using modulated light as an information carrier for a living biological receiver?
I would be especially interested in references to experiments where the temporal or spatial structure of an optical signal, rather than simply its average intensity or wavelength, produces a corresponding structured biological response.