I will be speaking a great deal about femtoseconds or an increment of 10-15 th of one second. It might be worthwhile considering how short this interval really is:
A quote: “The number of femtoseconds in a second is far greater than the number of seconds in a human lifespan”.
The retina is structured at the plane of receptor outer segments of an array of millions of individual nano-antennas that are responsive to the wave nature of light. Individual antennas are spatially dimensioned within the wavelength of light (the ‘near field’) and possess characteristics necessary to function electronically in very fast time.
I propose that this array acquires a very fast succession of completely formed images of the visual scene on a time scale of femtoseconds – thus of the extraordinary number of the order of 1015 images per second
I have previously proposed that it is phononic/solitonic transport of energy from wave absorption space to quantum confined electron endpoint in the structure of each nano-anntenna that provides the short term memory (‘Memristor’) function that allows image formation in this time frame.
And then….it follows from a Poisson calculation of light fluence on the retina in the femtosecond time frame yields the surprising result that the probability of two photons falling on the same site is vanishingly small. The retina is then a ‘photon counter’ and each individual ‘femtosecond frame’ in this succession of images consists of millions of single photon* interactions.
*Deferring to common usage I will continue to use the term ‘photon’ although in the spirit of this work one will recognize that ‘quantized interaction’ from absorbed light wave to quantized electron particle should more properly be used.
I believe that this image composed of single photon interactions underlies the recognized sensitivity of the vision process at this level. It has long been known (as recounted by Albert Rose) that vision can perceive an image that was initiated by a few as 2-10 photons.
This implies that the femtosecond ‘photon image’ acquired at the plane of receptor outer segments is transmitted through underlying retinal processes and the optic nerve to the visual centers of the brain.
This evidence would suggest that the train of ‘single photon’ images obtained at the plane of receptor outer segments, after ‘thermalization’ to human nervous system proportion by biochemical processes in the underlying retina, is transmitted as a coherent (i.e., equally spaced as an oscillation) train of completely formed images through the fiber bundle of the optic nerve to the brain. The slower processes of the biochemical processes of the retina probably ‘slow down the train’ perhaps extending the interval between images but it seems clear that the image as an array of single photon pixels arrives at and is so processes by the brain.
Thus we envision that the train of the order of 1015 / sec images arriving at the visual centers of the brain. This number is incomprehensible to us but probably represents the ‘quantum regime’. Lest one casually dismiss this magnitude as beyond the pale, I have continually noted what I believe to be the seminal nature of a paper by Fleming’s group at Berkeley* reporting femtosecond spectrosscopy measuremnts made on another photosensitive system – plant photosynthesis system. To note: photo absorption in plants uses the same nano-antenna light absorption principle as the retina of the eye although as would be expected in this non-imaging geometry the nano-antenna structures are array in parallel to generate power not an image – the grana and stroma of the chloroplast organelle
* Gregory Engel et al, “Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems”, Nature, Vol 446/12, April 2007
This is in the realm of quantum coherence and it predicts that this time scale will lead to greater understanding of brain function. I note again as we proceed into the femtosecond time regime the measurements made by Engel et al* A quote from that paper seems prescient: “This wavelike (i.e., quantum coherent) characteristic of energy transfer within the photosynthetic complex……..allows the complexes to sample vast areas of phase space to find the most efficient path”.