Photon Realisation


The other day I read about how scientists have been able to stop photons of light for the first time in history, and after a brief time let them continue their journey. I was initially very impressed.

Coincidently I have just started reading Richard Dawkins "The Blind Watchmaker" and near the end of the first chapter he describes an eye as an example of a complex mechanism that could not exist by chance, and instead must have evolved. This shows in minute detail how it works, including the inside of rods; with their nucleus, mitotecocus, and Photoreceptor cells. I had not seen this before in a diagram of the eye.

I was shocked, the human eye catches and effectively stops photons!

Once I read this, it seemed obvious but I had never considered this before now. Photons are not reflected out of the eye, nor do they pass out of the back of our skull. Instead they are absorbed in the retina at the back of the eye. We are effectively consuming light!

What does the body do with photons that are caught? With my limited knowledge it would seem unlikey that they are passed on directly to the visual cortex through the optic nerve. Something is passed on though, perhaps the photons are converted to electrical/chemical signals and only then then passed on, the energy in the photon being the driving force in the reaction.

These signals are then converted by the visual cortex to a projection of reality inside our brain. This is going to sound obvious but It helps me clarify a point. Our eyes are not the ones doing the seeing, they are just receptors for light radiation, it is the brain that interprets this and it give us the image we see and we are not seeing it directly but it is like a projector and a screen in a cinema.

I find myself thinking now, if we are catching photons, what else does? Do photographic films catch photons? do photographs represent the impression of a collection of photons caught by the film, I guess they do ;0\ Photography really is the process of catching photons!

Video is also the same principle, although using a different capture technique and being many times a second. Photosynthesis in plants is the process of catching photons. Infact most things absorb photons, and its basic physics that the reflected light is photons that are not absorbed.

Shit, there's so much out there that stops photons already. Why should we care that scientists can stop light in a lab? and why is this new to me? I know all this already!

Perhaps the key is that they let it go again and it continued its journey without having lost any energy, and that is new.


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